Imaging Pearls ❯ Kidney ❯ Transitional Cell Carcinoma: TCC
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- Purpose: To assess the proportion of upper tract urothelial carcinomas (UTUC) that are evident without the excretory phase at CT urography (CTU), and the proportion of potentially avoidable radiation
Conclusion: In our population, almost all UTUCs were evident via primary or secondary imaging findings without requiring the excretory phase. These results support streamlining protocols and pathways.
Is the excretory phase necessary to identify upper tract urothelial neoplasms at CT urography? A 10-year population-based study
Warda Limaye · Andrew Fenwick · Ross Mason · Andreu F. Costa
Abdominal Radiology (2024) 49:2296–2304 - In this study, we evaluated the imaging of all documented cases of UTUC over a 10-year period in a defined population. We found that almost all UTUCs (97.1%) imaged with CTU were evident as either a primary mass or via secondary findings and did not require the excretory phase for diagnosis. Moreover, in most patients (93.2%) imaged with non-CTU examinations, a primary mass and/or secondary imaging finding were evident that would enable a diagnosis of UTUC. In other words, only a very small proportion of UTUCs are exclusively evident as filling defects in the excretory phase of a CTU. Our findings show that the excretory phase adds little diagnostic value to the diagnosis of UTUC, suggesting that this phase could potentially be recommended omitting the excretory phase altogether. Results from our study add to the growing body of literature that show a very low probability that UTUC is solely evident on imaging as a filling defect in the excretory phase.
Is the excretory phase necessary to identify upper tract urothelial neoplasms at CT urography? A 10-year population-based study
Warda Limaye · Andrew Fenwick · Ross Mason · Andreu F. Costa
Abdominal Radiology (2024) 49:2296–2304 - “Our study had limitations. This was a retrospective study of a defined population, which can introduce bias and limit generalizability. As this study evaluated the frequency of imaging findings of UTUC, only patients with UTUC were included, and imaging readers were not blinded to the diagnosis of UTUC. This does not reflect real-world practice and represents a potential source of bias, which can lead to overestimation in the reliability of radiologists and imaging to detect UTUC, as well as potential radiation dose savings. Evaluation of real-world sensitivity, specificity, and accuracy of CTU requires a case-control study design and blinded readers; this was outside the scope of this study.”
Is the excretory phase necessary to identify upper tract urothelial neoplasms at CT urography? A 10-year population-based study
Warda Limaye · Andrew Fenwick · Ross Mason · Andreu F. Costa
Abdominal Radiology (2024) 49:2296–2302 - “In conclusion, in our population almost all documented UTUCs were evident on imaging examinations as either a primary mass or via secondary findings. Only a small minority of UTUCs were exclusively evident as filling defects in the excretory phase of a CTU examination. Deferring the excretory phase to cases with initial negative work-up or assessing whether one is necessary at the time of the examination can reduce radiation dose by approximately 44%. Radiation dose and healthcare costs associated with CTU can be further avoided by adhering to updated guidelines. These results should be considered when designing CT protocols, patient pathways, and imaging guidelines for patients with suspected UTUC. ”
Is the excretory phase necessary to identify upper tract urothelial neoplasms at CT urography? A 10-year population-based study
Warda Limaye · Andrew Fenwick · Ross Mason · Andreu F. Costa
Abdominal Radiology (2024) 49:2296–2302 - “Nonneoplastic lesions of the urinary system can mimic upper tract cancers, including hematomas, sloughed papillae, urolithiasis, fibroepithelial polyps (FPs), endometriosis, malacoplakia, infection, and tuberculosis (TB) among others. UTUC mimics can be divided based on their location in the upper tract as discussed in the following sections.”
Urologic Imaging of Collecting System and Ureters: Cancers and Mimics
Soumyadeep Ghosh et al.
Urol Clin N Am - (2024) in press - “Upper tract urothelial tumor histologic subtypes include papillary noninvasive lesions (papilloma, papillary urothelial neoplasm of low malignant potential [PUNLMP], and low-grade and high-grade papillary carcinomas), carcinoma in situ, and carcinomas. Upper tract PUNLMP is extremely rare and upper tract low-grade carcinoma is less common compared to its lower tract counterpart. High grade carcinomas, often invasive at presentation, comprise most upper tract tumors (about 70% of all renal pelvic tumors).”
Urologic Imaging of Collecting System and Ureters: Cancers and Mimics
Soumyadeep Ghosh et al.
Urol Clin N Am - (2024) in press - “The incidence of ureteric wall metastases—one of the rare causes of ureteral obstruction—is about 0.37%. In order of decreasing frequency, primary malignancies metastasizing to the ureters include the breast and gastrointestinal tract (50%), prostate and cervix (40%), stomach, and lungs. Patients are either asymptomatic or may present with back pain (50%), dysuria, proteinuria, and hematuria. Metastases may present as small intraluminal nodular filling defects or masses encasing or obliterating the ureteral lumen with varying degrees of upstream obstruction.”
Urologic Imaging of Collecting System and Ureters: Cancers and Mimics
Soumyadeep Ghosh et al.
Urol Clin N Am - (2024) in press - - Lymphomatous involvement of the urinary tract has varied manifestations, some mimicking urothelial lesions. Bilateral involvement and bulky lymphadenopathy or disease elsewhere in the abdomen should raise suspicion for lymphoma.
- IgG4-related disease can involve the collecting system as well as periureteric tissues. Disease involving other typical locations in the body, elevated serum IgG4 levels and biopsy of soft tissue masses may be required for making a definitive diagnosis.
- Urinary tract TB is another mimicker of UTUC. Imaging features such as papillary necrosis, and calyceal deformities (moth-eaten calyx), strictures with caliectasis, infundibular stenosis or amputation of the calyces, pelvic or ureteral strictures with alternating dilated and constricted segments and a diffusely thickened, small volume urinary bladder are some imaging clues seen in GUTB.
Urologic Imaging of Collecting System and Ureters: Cancers and Mimics
Soumyadeep Ghosh et al.
Urol Clin N Am - (2024) in press - “The past decade has seen dramatic changes in the understanding and risk tolerance of the nephrotoxic potential of IV administered ICM. Previous clinical guidelines that considered all ICM administrations as potentially nephrotoxic and potentially lethal have given way to a nuanced understanding and risk-stratified approach to ICM administration. For most patients with normal to moderately compromised renal function (eGFR ≥ 30 mL/min/1.73 m2), consensus now exists among radiologists and nephrologists that modern ICM is safe and does not pose an increased risk of AKI or AKI-related adverse outcomes.”
Risk of Acute Kidney Injury Following IV Iodinated Contrast Media Exposure: 2023 Update, From the AJR Special Series on Contrast Media
Jennifer S. McDonald, Robert J. McDonald
AJR 2024; 223:e2330037
- Seer Data 2022-TCC
- NIH NCI Data 2022
Transitional cell carcinoma of the renal pelvis, accounting for only 7% of all kidney tumors, and transitional cell cancer of the ureter, accounting for only 1 of every 25 upper urinary tract tumors, are curable in more than 90% of patients if they are superficial and confined to the renal pelvis or ureter.” - Seer Data 2022-TCC
- Urothelial Cancers: facts
- Make up 10-15% of all renal tumors
- 90% are transitional cell carcinomas, 9% are squammous cell carcinoma and 1% are mucinous adenocarcinoma
- Average age is 6-7th decade of life
- Male to female ratio is 3-1
- 40% of patients with upper tract TCC will develop metachronous TCC of the lower urinary tract - TCC Staging
- Localized
--- Patients with localized disease may be classified into three groups:
------ Group 1: Low-grade tumor confined to the urothelium without lamina propria invasion (papilloma grade I transitional cell cancer).
------ Group 2: Grade I–III carcinomas without demonstrable subepithelial invasion or focal microscopic invasion or papillary carcinomas with carcinoma in situ and/or carcinoma in situ elsewhere in the urothelium.
------ Group 3: High-grade tumors that have infiltrated the renal pelvic wall or renal parenchyma or both but remain confined to the kidney. Infiltration of muscle in the upper tract may not be associated with as much potential for distant dissemination as appears to be the case for bladder cancer.
- Regional
------ Group 4: Extension of tumors beyond the renal pelvis or parenchyma and invasion of peripelvic and perirenal fat, lymph nodes, hilar vessels, and adjacent tissues.
- Metastatic
--- Spread of the tumor to distant tissues. - Purpose of review
To assess patterns of presentation, diagnostics and treatment in patients with upper tract urothelial carcinoma (UTUC), a multicentre registry was launched. Clinical data of UTUC patients were prospectively collected over a 5-year period.
Recent findings
Data from 2380 patients were included from 2014 to 2019 (101 centres in 29 countries). Patients were predominantly male (70.5%) and 53.3% were past or present smokers. The majority of patients (58.1%) were evaluated because of symptoms, mainly macroscopic hematuria. Computed tomography (CT) was the most common performed imaging modality (90.5%).
Contemporary patterns of presentation, diagnostics and management of upper tract urothelial cancer in 101 centres: the Clinical Research Office of the Endourological Society Global upper tract urothelial carcinoma registry,
Baard, Joyce et al.
Current Opinion in Urology: July 2021 - Volume 31 - Issue 4 - p 354-362 - “Our data is in line with the known epidemiologic characteristics of UTUC. CT imaging is the preferred imaging modality as also recommended by guidelines. Diagnostic URS (ureteroscopy) gained a stronger position, however, in almost half of patients a definitive treatment decision was made without complete endoscopic information. Only one-third of patients with UTUC are currently treated with kidney sparing surgery.”
Contemporary patterns of presentation, diagnostics and management of upper tract urothelial cancer in 101 centres: the Clinical Research Office of the Endourological Society Global upper tract urothelial carcinoma registry,
Baard, Joyce et al.
Current Opinion in Urology: July 2021 - Volume 31 - Issue 4 - p 354-362 - “The major risk factors for urothelial carcinoma of the upper urinary tract include male gender, increasing age, cigarette smoking and tobacco use, phenacetin abuse, exposure to certain chemicals and drugs (such as cyclophosphamide), chronic hydronephrosis, and a history of prior recurrent or severe urinary tract infections..”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - “Urothelial cancer (UC) constitute up to 10% of neoplasms of the upper urinary tract. UC occurs most frequently in the extrarenal part of the renal pelvis, followed by the infundibulocaliceal region. When manifesting as an infiltrative pattern, UC expands out of the renal pelvis into the parenchyma with distortion of the normal renal corticomedullary architecture with preservation of the reniform shape, which is not typically the case in RCC.”
CT imaging spectrum of infiltrative renal diseases David H.
Ballard et al.
Abdom Radiol (2017) 42:2700–2709 - “However, the utility of CT urography, whether in the upper or lower urinary tract, is heavily contingent on the use of optimized CT protocols and proper image acquisition techniques, because poor technique can create significant barriers to making a correct radiologic interpretation, particularly given that identification of subtle tumors can be nearly impossible in the absence of good collecting system distension and opacification. Moreover, although standard axial image review may be sufficient in most other parts of the abdomen and pelvis, evaluation of the collecting systems and ureters presents a prime example of an application for which standard axial images may not be sufficient to identify many subtle urothelial tumors, and for which the use of multiplanar reformations and three-dimensional (3D) imaging techniques may be helpful (or even necessary) for the identification of small or difficult-to-see lesions.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - “In particular, our own experience has suggested that these reconstructions are particularly helpful in evaluating the ureters, where subtle urothelial thickening or even ureteral strictures are easy to overlook on the source axial images (and are commonly missed), whereas these abnormalities tend to be more conspicuous using a coronal MIP reconstruction. In particular, MIP images allow the entirety of the collecting systems and ureters to be viewed at a single glance (providing a global overview of the collecting systems), which is a great advantage compared with standard axial image review, in which the intrarenal collecting systems and ureters are constantly moving in and out of plane, making careful evaluation difficult.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - “The identification of transitional cell carcinomas throughout the upper and lower urinary tract (including the intrarenal collecting systems, ureters, and bladder) can be very difficult, and relies on several subtle imaging features. However, it is important to be cognizant that the identification of these imaging features is heavily contingent on proper imaging technique and protocol design. Failure to acquire the correct contrast enhancement phases, or, alternatively, failure to adequately distend the collecting system, can make identification of even large tumors difficult.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - Urothelial Cancers: CT Findings
- Single or multiple sessile filling defects that compress the renal sinus fat
- Pelvicaliceal irregularities (stricture like)
- Focal or diffuse mural thickening
- Caliceal amputation
- Tumor filled distended calices - Transitional Cell Carcinoma: Differential Diagnosis
- Large TCC’s may look similar to
--- Infiltrating renal cell carcinoma
--- Lymphoma
--- Metastases
--- Xanthogranulomatous pyelonephritis - “The most common imaging manifestation of transitional cell carcinoma in the ureters is urothelial thickening, particularly focal thickening or a short-segment ureteral stricture. Similar to other sites in the urinary tract, diffuse or bilateral urothelial thickening in the ureters is unlikely to represent malignancy, and is much more likely to represent an ascending urinary tract infection (particularly when associated with diffuse bladder wall thickening secondary to cystitis).”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - “As with other portions of the urinary tract, transitional cell carcinomas in the ureter are often hypovascular, making it critical that the field of view includes the entirety of the ureters during the arterial phase acquisition. Any focal or irregular urothelial hyperenhancement should raise concern for malignancy, and, in some instances, there may be associated tumor neovascularity.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography
Siva P. Raman, MD*, Elliot K. Fishman
Urol Clin N Am 45 (2018) 389–405 - “ The hallmark of TCC is multiplicity and recurrence. Nearly 2-4% of patients with bladder cancer develop upper tract TCC, but 40% of patients with upper tract TCC develop bladder cancer.”
Imaging and Staging of Transitional Cell Carcinoma: Part 2, Upper Urinary Tract
Vikram R et al
AJR 2009;192:1488-1493 - Ureteral TCC
- 2,290 patients and 700 deaths in 2008
- Can occur anywhere in the ureter
--- Distal ureter lesions account for ¾ of cases
--- Unfortunately, distal ureter is the most difficult to consistently distend and visualize well.
- Ureter rarely involved by lymphoma and metastatic disease (breast, GI, prostate, cervix, and RCC) - Ureteral TCC: Imaging Findings
- Urothelial thickening
- Abnormal urothelial enhancement
--- Particularly when asymmetric, focal, and in conjunction with thickening
- Ureteral calcification
- Periureteral fat stranding
- Discrete filling defect or mass
- Look for site of transition and proximal hydronephrosis & hydroureter - Mimics on Imaging
- Lymphoma
- Metastatic disease
--- Breast cancer, GI tract malignancies, prostate cancer, cervical cancer
- Infiltrating variants of RCC
- Xanthogranulomatous Pyelonephritis (XGP) - Infiltrative Renal Lesions on CT
- Renal cell carcinoma
- Urothelial tumor (TCC)
- Renal lymphoma
- Renal sarcoma/plasmacytoma/metastasis
- Acute pyelonephritis
- Renal contusion
- Radiation therapy
- IgG4 Renal disease - “In conclusion, this study revealed the radiologic characteristics of IgG4-related lesions involving the upper urinary tract compared with those of urothelial carcinoma. CT findings suggestive of IgG4-related upper urinary tract lesions in comparison with urothelial carcinoma are bilateral and have longer urinary tract involvement; extramural growth pattern; ill-defined margins; a gradual enhancement pattern in the dynamic CT study; aortic involvement; and fat stranding in the paraaortic space, presacral space, or pelvic wall areas. IgG4-related disease can also manifest as unilateral lesions, which could appear similar to those of urothelial carcinoma and be difficult to differentiate.”
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Minobu Kamo et al.
AJR 2020; 215:406–412 - “CT findings suggestive of IgG4-related upper urinary tract lesions in comparison with urothelial carcinoma are bilateral and have a longer urinary tract involvement and exhibit an extramural growth pattern, ill-defined margins, a gradual enhancement pattern, aortic involvement, and fat stranding in the paraaortic, presacral, or pelvic wall areas.”
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Minobu Kamo et al.
AJR 2020; 215:406–412 - Microhematuria should be defined as ≥3 red blood cells per high power field on microscopic evaluation of a single specimen. In patients diagnosed with gynecologic or non-malignant genitourinary sources of microhematuria, clinicians should repeat urinalysis following resolution of the gynecologic or non-malignant genitourinary cause. The Panel created a risk classification system for patients with microhematuria, stratified as low-, intermediate-, or high-risk for genitourinary malignancy. Risk groups were based on factors including age, sex,smoking and other urothelial cancer risk factors, degree and persistence of microhematuria, as well as prior gross hematuria. Diagnostic evaluation with cystoscopy and upper tract imaging was recommended according to patient risk and involving shared decision-making. Statements also inform follow-up after a negative microhematuria evaluation.
Microhematuria: AUA/SUFU Guideline
Daniel A. Barocas et al.
J Urol 2020 Oct;204(4):778-786. 
- - An infiltrative renal pelvic UCC should be considered when a central, poorly marginated mass extending into the adjacent parenchyma is seen at imaging, especially if an additional lesion is identified in the urinary tract.
- The combination of infiltrative renal masses in the presence of bulky perinephric disease, widespread lymphadenopathy, splenomegaly, and bilateral involvement is suggestive of lymphoma. In many cases, patients have an established diagnosis of lymphoma at the time of imaging.
Infiltrative Renal Malignancies: Imaging Features, Prognostic Implications, and Mimics
Sweet DE et al.
RadioGraphics 2021; 41:0000–0000
- “Bilaterality (p < 0.0001), an extramural growth pattern (p < 0.0001), a great- er number of affected segments (p = 0.04), and a gradual dynamic enhancement pattern (p < 0.001) were significantly more frequent in patients with IgG4-related disease. With regard to extraurinary findings, paraaortic fat stranding (p = 0.03), presacral fat stranding (p < 0.001), fat stranding of the pelvic walls (p < 0.001), and aortic involvement (p < 0.001) were seen more frequently in patients with IgG4-related disease; on the other hand, there was no statistically significant difference in terms of frequency of pancreatic involvement. Hydronephrosis and renal involvement were seen more frequently in patients with urothelial carcinoma, although the difference was not statistically significant.”
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Kamo M et al.
AJR 2020; 215:406–412 - "CT findings suggestive of IgG4-related upper urinary tract lesions in comparison with urothelial carcinoma are bilateral and have a longer urinary tract involve- ment and exhibit an extramural growth pattern, ill-defined margins, a gradual enhancement pattern, aortic involvement, and fat stranding in the paraaortic, presacral, or pelvic wall areas.”
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Kamo M et al.
AJR 2020; 215:406–412 - "In this study, findings of bilateral involvement and longer urinary tract involvement, extramural growth pattern, ill-defined margins, and gradual enhancement pattern in the dynamic CT study were more suggestive of IgG4-related upper urinary tract lesions than they were of urothelial carcinoma. Furthermore, extraurinary findings such as fat stranding in the paraaortic space, presacral space, and pelvic wall were identified as CT findings suggestive of IgG4-related disease.”
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Kamo M et al.
AJR 2020; 215:406–412 - “CT findings suggestive of IgG4-related upper urinary tract lesions in comparison with urothelial carcinoma are bilateral and have longer urinary tract involvement; extramural growth pattern; ill-defined margins; a grad- ual enhancement pattern in the dynamic CT study; aortic involvement; and fat stranding in the paraaortic space, presacral space, or pelvic wall areas. IgG4-related disease can also manifest as unilateral lesions, which could appear similar to those of urothelial carcinoma and be difficult to differentiate."
CT Findings of Upper Urinary Tract Lesions in IgG4-Related Disease: Comparison With Urothelial Carcinoma
Kamo M et al.
AJR 2020; 215:406–412
- “Urothelial carcinoma of the upper urinary tract (renal collecting system and ureter) is a relatively uncommon malignancy, accounting for 5–7% of urothelial tumors and up to 10–15% of all renal tumors. The exact incidence of upper urinary tract urothelial carcinoma is difficult to assess, given its rarity; about 2290 Americans were diagnosed with ureteral urothelial carcinoma, and nearly 700 patients died from it in 2008 . The renal pelvis is the most commonly involved site in the UUT , and is second to the urinary bladder in overall incidence of urothelial carcinoma.”
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali1 · Elliot Fishman1 · Sheila Sheth1
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - Multifocality is a key feature in urothelial carcinoma warranting long-term surveillance. Up to 40% of patients with UUT urothelial carcinoma will develop a metachronous tumor in the urinary bladder, usually within the first 2 years following surgical resection, and this is typically seen more with ureteric tumors than with renal pelvic tumors. Approximately, 2–9% of patients with urothelial carcinoma of the urinary bladder have a metachronous upper tract urothelial carcinoma.
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali1 · Elliot Fishman1 · Sheila Sheth1
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - “When the ureter is affected, the most commonly involved segment is the distal third (73%), followed by the mid ureter (24%), and proximal ureter (3%). Bilateral ureteral involvement occurs in 2–5% of cases . Approximately, 11–13% of patients with upper tract urothelial carcinoma develop metachronous upper tract tumors. Patients usually pre- sent with microscopic or gross hematuria, flank pain, or renal colic. However, up to 20% of lesions are detected incidentally or during surveillance imaging for a known urothelial tumor in the urinary bladder.”
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali · Elliot K. Fishman · Sheila Sheth
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - “Papillary forms of urothelial carcinoma in the upper urinary tract, which accounts for up to 85% of urothelial carcinomas, are cytologically and histologically similar to their urinary bladder counterpart. These tumors are usually low-stage and superficial, with frondlike morphology, and tend to have a slow growth rate with a relatively indolent course. Solid, flat tumors, accounting for approximately 15% of cases, tend to be more aggressive with a higher stage at presentation.
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali · Elliot K. Fishman · Sheila Sheth
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - “Accurate diagnosis of UTT urothelial carcinoma requires careful evaluation of the source axial images in combination with multiplanar and 3D reconstructions. In fact, 3D reconstructions have become an integral part of CTU in recent years, as multidetector technology allows acquisition of isotropic source images. At our institution, the source axial images (0.5 mm) are sent to a separate workstation for creation of three sets of 3D reconstructions: maximum intensity projection (MIP), traditional volume-rendered reconstructions (VR), and virtual ureteroscopy images (specialized volume-rendered images).”
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali · Elliot K. Fishman · Sheila Sheth
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - “3D reconstructions, although a useful complementary tool in detection of subtle urothelial carcinomas, are sus- ceptible to suboptimal distension of the collecting system and ureteral peristalsis, and both these limitations can be mistakenly interpreted as strictures. In addition, tumors pro- ducing soft tissue thickening without narrowing of the lumen are best demonstrated on the axial images [2]. Therefore, it is imperative to cross-reference the 3D images with axial source images to avoid these potential pitfalls.”
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali · Elliot K. Fishman · Sheila Sheth
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2 - “Urothelial carcinoma of the upper urinary tract is a relatively uncommon malignancy. Multifocality and high rates of recur- rence are key features of these tumors. The CTU protocol focuses on maximizing ureteral distension to optimize detec- tion of small lesions in the collecting system. 3D imaging helps maximize sensitivity of CTU in detection of subtle tumors. CTU tends to perform well in differentiating early stage from advanced-stage tumors; however, it is not that accurate in dif- ferentiation among early-stage tumors (Ta, T1, and T2).”
Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease
Osama Ali · Elliot K. Fishman · Sheila Sheth
Abdominal Radiology https://doi.org/10.1007/s00261-019-02173-2
- “Upper tract urothelial carcinoma (UTUC) is a relatively uncommon but aggressive genitourinary malignancy for which multi-phase contrast-enhanced computed tomography (CT) plays an important role in evaluation and staging. 3D imaging with maximum intensity projection (MIP) and volume-rendered (VR) images has been described as a useful means of evaluating UTUC. In this study, we describe the technique of a novel 3D methodology known as cinematic rendering (CR) and provide clinical examples of UTUC visualized with CR. CR utilizes a complex universal lighting model in order to create photorealistic images with improved detail and depth in comparison to MIP or VR images.”
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5 - “The ability to use multiple overlapping soft-tissue trapezoids to create complex variations in the visibility, translucency, and color of different structures within the imaged volume is another aspect of CR that requires further study. In the case series presented in this study, this principle of CR is perhaps best displayed in Figs. 3d and 4c, d, where the CR visualizations were manipulated to emphasize intraluminal details within the renal collecting systems and ureters. In a way, this could be thought of as similar to minimum intensity projection (MinIP), although in our experience it has been possible to display intraluminal findings as well as preserve the display of other soft tissue types in a manner that is not typically performed with MinIP images.”
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5 
- As with other regions with complex anatomy for which 3D visualization is a helpful adjunct to standard axial and multiplanar reformatted images, the evaluation of UTUC with CR may ultimately be found to provide important information regarding lesion identification and characterization, as well as therapeutic planning. Further study of the role of CR in UTUC should be carried out to investigate the impact on lesion detection and classification as well as in patient triage and management.
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5
- “Upper tract urothelial carcinoma (UTUC) is a relatively uncommon but aggressive genitourinary malignancy for which multi-phase contrast-enhanced computed tomography (CT) plays an important role in evaluation and staging. 3D imaging with maximum intensity projection (MIP) and volume-rendered (VR) images has been described as a useful means of evaluating UTUC. In this study, we describe the technique of a novel 3D methodology known as cinematic rendering (CR) and provide clinical examples of UTUC visualized with CR. CR utilizes a complex universal lighting model in order to create photorealistic images with improved detail and depth in comparison to MIP or VR images.”
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5 - “The ability to use multiple overlapping soft-tissue trapezoids to create complex variations in the visibility, translucency, and color of different structures within the imaged volume is another aspect of CR that requires further study. In the case series presented in this study, this principle of CR is perhaps best displayed in Figs. 3d and 4c, d, where the CR visualizations were manipulated to emphasize intraluminal details within the renal collecting systems and ureters. In a way, this could be thought of as similar to minimum intensity projection (MinIP), although in our experience it has been possible to display intraluminal findings as well as preserve the display of other soft tissue types in a manner that is not typically performed with MinIP images.”
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5 - As with other regions with complex anatomy for which 3D visualization is a helpful adjunct to standard axial and multiplanar reformatted images, the evaluation of UTUC with CR may ultimately be found to provide important information regarding lesion identification and characterization, as well as therapeutic planning. Further study of the role of CR in UTUC should be carried out to investigate the impact on lesion detection and classification as well as in patient triage and management.
The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice
Steven P. Rowe · Linda C. Chu · Alexa R. Meyer · Michael A. Gorin · Elliot K. Fishman
Abdominal Radiology 2019 (in press) https://doi.org/10.1007/s00261-019-02154-5
- “Computed tomography (CT) urography is the best noninvasive method of evaluating the upper urinary tract for urothelial malignancies. However, the utility of CT urography is heavily contingent on the use of proper image acquisition protocols. This article focuses on the appropriate protocols for optimizing CT urography acquisitions, including contrast administration and the timing of imaging acquisitions, as well as the use of ancillary techniques to increase collecting system distention. In addition, imaging findings are discussed that should raise concern for urothelial carcinoma at each of the 3 segments of the urinary tract: the intrarenal collecting systems, ureters, and bladder.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “One of the unique features of transitional cell carcinoma, regardless of whether it arises in the upper or lower urinary tract, is its strong tendency for both recurrence and multifocality, with almost 4% of patients with bladder cancer going on to develop a transitional cell carcinoma in the upper urinary tract.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “A study by Dillman and colleagues found inferior urinary tract distension with the split-bolus technique. In our own experience, this protocol is particularly problematic when evaluating the ureters, with poor distention of the distal ureters. Another potential disadvantage of this protocol is decreased sensitivity for small or subtle renal cell carcinomas, because only 2 postcontrast phases are available for eval- uation of the renal parenchyma, as opposed to 3 phases in the single-bolus technique.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “In patients less than 35 years old, ostensibly at much lesser risk of developing renal malignancies, we acquire only noncontrast, arterial, and delayed phase images, because the odds of the patient having either a renal parenchymal lesion or a significant abnormality in the other parenchymal organs of the upper abdomen are much less, making venous phase acquisitions of less value.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “In particular, MIP images allow the entirety of the collecting systems and ureters to be viewed at a single glance (providing a global overview of the collecting systems), which is a great advantage compared with standard axial image review, in which the intrarenal collecting systems and ureters are constantly moving in and out of plane, making careful evaluation difficult.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “Diffuse bladder wall thickening is very unlikely to represent malignancy, and most often represents infectious cystitis or an artificially thickened bladder wall caused by bladder decompression. However, the presence of focal or asymmetric bladder wall thickening should always raise concern for malignancy, and should prompt further evaluation with cystoscopy.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “Accordingly, some sites of subtle urothelial thickening may be more apparent on the arte- rial phase images as a result of associated hypervascularity and enhancement. In general, any type of urothelial thickening, when focal, should raise concern for malignancy, with many ureteral tumors showing irregular, nodular soft tissue thickening, rather than circumferential or smooth wall thickening.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241. - “The presence of focal wall thickening or a discrete nodule/mass should raise concern for the presence of malignancy anywhere in the upper or lower urinary tract and should prompt further evaluation with direct visualization. Nevertheless, there are multiple benign entities that could potentially mimic findings of malignancy. In particular, urothelial thickening is a common finding, and, when bilateral and diffuse throughout the collecting systems, is much more likely to be the sequela of infection, rather than tumor, particularly when the wall thickening is smooth and regular.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Raman SP, Fishman EK Radiol Clin North Am 2017 Mar;55(2):225-241.
- “ Moreover, although standard axial image review may be sufficient in most other parts of the abdomen and pelvis, evaluation of the collecting systems and ureters presents a prime example of an application for which standard axial images may not be sufficient to identify many subtle urothelial tumors, and for which the use of multiplanar reformations and three-dimensional (3D) imaging techniques may be helpful (or even necessary) for the identification of small or difficult-to-see lesions.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “Urothelial carcinoma of the upper urinary tract (including the intrarenal collecting systems, renal pelvis, and ureters) is uncommon, although the renal pelvis is probably the second most common location for urothelial carcinoma following the bladder. Although exact numbers are difficult to obtain for the incidence of upper urinary tract tumors given their rarity, it is thought that roughly 2300 patients in the United States were diagnosed with transitional cell carcinoma of the ureter (with 700 deaths) in 2008. Upper tract tumors account for only 5% of all urothelial carcinomas and w15% of all renal tumors.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “A study by Dillman and colleagues found inferior urinary tract distension with the split-bolus technique. In our own experience, this protocol is particularly problematic when evaluating the ureters, with poor distention of the distal ureters. Another potential disadvantage of this protocol is decreased sensitivity for small or subtle renal cell carcinomas, because only 2 postcontrast phases are available for evaluation of the renal parenchyma, as opposed to 3 phases in the single-bolus technique.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “At our own institution, in patients who present with hematuria, we have made the decision that our primary goal is to maximize sensitivity for all renal malignancies (ie, both renal cell carcinoma and transitional cell carcinoma), and to make the diagnosis on the first attempt (rather than having patients be imaged repeatedly without a clear diagnosis being made). Accordingly, at our own institution we have decided to use the single- bolus technique, and in patients more than 35 years of age (at maximal risk for the development renal malignancies), we acquire 4-phase studies with separate noncontrast, arterial, venous, and delayed phase acquisitions.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “Subsequently, the source axial images (0.5 mm) are sent to an independent workstation for generation of 2 separate sets of 3D reconstructions, including maximum intensity projection (MIP) images and volume-rendered re- constructions. The MIP technique involves taking the highest attenuation voxels in a data set and projecting these voxels into a 3D display, which can be interactively rotated or manipulated by the interpreting radiologist.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “MIP images are particularly useful in evaluating the collecting systems and ureters, providing a good global overview of the high-density contrast within the collecting systems, and highlighting subtle sites of urothelial thickening, luminal narrowing, calyceal destruction, or asymmetric hydronephrosis/hydroureter. In particular, our own experience has suggested that these reconstructions are particularly helpful in evaluating the ureters, where subtle urothelial thickening or even ureteral strictures are easy to overlook on the source axial images (and are commonly missed), whereas these abnormalities tend to be more conspicuous using a coronal MIP reconstruction.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “In particular, MIP images allow the entirety of the collecting systems and ureters to be viewed at a single glance (providing a global overview of the collecting systems), which is a great advantage compared with standard axial image review, in which the intrarenal collecting systems and ureters are constantly moving in and out of plane, making careful evaluation difficult.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “This is one area in which the use of MIP images can be helpful in terms of providing a global overview of the ureters and collecting systems, and highlighting subtle differences in ureteral distention. Whenever asymmetric hydronephrosis or hydroureter is identified, the ureter should then be followed along its course to identify a potential transition point or change in caliber that might suggest an obstructing tumor.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “Given this overlap between benign and malignant entities, it is not surprising that the positive predictive value of CT urography for up- per tract urinary malignancy may be as low as 53% (with a positive predictive value of only 46% for urothelial thickening), although this increases in patients with a discrete mass, for which the positive productive value may be as high as 83%.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016) - “The identification of transitional cell carcinomas throughout the upper and lower urinary tract (including the intrarenal collecting systems, ure- ters, and bladder) can be very difficult, and relies on several subtle imaging features. However, it is important to be cognizant that the identification of these imaging features is heavily contingent on proper imaging technique and protocol design. Failure to acquire the correct contrast enhance- ment phases, or, alternatively, failure to adequately distend the collecting system, can make identification of even large tumors difficult.”
Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography Siva P. Raman, Elliot K. Fishman Radiol Clin N Am - (2016)
- Transitional Cell Carcinoma
- Roughly 2300 new cases of TCC every year
- 700 deaths per year
- 10% of all renal neoplams
- Men outnumber women 3:1
- Most common in patients over 60
- Most commonly presents with hematuria - Risk Factors
- Cigarette Smoking
- Analgesic abuse
- Chemical carcinogens
- Aniline dyes
- Cyclophosphamide therapy
- Caffeine use (especially with heavy use) - Intrarenal Collecting System TCC:
Imaging Findings
- Urothelial thickening and enhancement
- Focally dilated calyx
- “Amputated” calyx
- Irregularity and destruction of a calyx
- Infiltrative hypodense mass - Ureteral TCC
- 2,290 patients and 700 deaths in 2008
- Can occur anywhere in the ureter
- Distal ureter lesions account for ¾ of cases
- Unfortunately, distal ureter is the most difficult to consistently distend and visualize well.
- Ureter rarely involved by lymphoma and metastatic disease (breast, GI, prostate, cervix, and RCC) - Bladder TCC
- Bladder cancer is the 4th most common malignancy in men and 10th most common malignancy in women
- 61000 new cases and 13000 deaths each year
- 90% of bladder cancers are TCC (4% squamous cell carcinoma, 1% adenocarcinoma)
- 70% are superficial and have relatively good prognoses
- When metastatic, prognosis is much worse (5% at 2 years) - Bladder TCC
- CT is a better modality for the identification of bladder cancer than most radiologists think.
- “The overall sensitivity, specificity, accuracy, PPV, and NPV for bladder cancer detection were 79%, 94%, 91%, 75%, and 95% for CT urography”
Sadow CA et al. Radiology 2008 - Bladder Cancer Enhancement
- Wide variability in degree of enhancement
- “17 (85%) of 20 bladder cancers enhanced maximally to approximately 106 HU around the 60 second scan delay and washout out slowly thereafter”
Kim KK et al. Radiology 2004.
- Most bladder TCCs will show early enhancement and will be best visualized in a well-distended bladder with unenhanced urine.
- Stresses importance of arterial phase imaging through distended bladder
- Patients should not void for at least 1 hour prior to scan - Bladder Cancer Imaging Appearance
- Asymmetric wall thickening
- Diffuse bladder wall thickening is rarely cancer (i.e. cystitis, bladder outlet obstruction, neurogenic bladder)
- Focal mass
- Small filling defect
- Calcification in bladder wall - Hematuria
- Microscopic hematuria has a prevalence of 2.5% in asymptomatic patients
- Cause for abnormality not found in many patients
- These patients need further work-up depending on risk factors
- Macroscopic hematuria much more concerning
- Risk of malignancy ranges from 3 – 6%
- Requires evaluation of the upper tracts with CT and bladder with cystoscopy - Risk Factors for Urologic Malignancies
- Age > 40
- Gross hematuria
- Smoking
- Obesity
- Analgesic abuse
- Chemical carcinogen exposure
- Occupational exposures
- Chronic inflammatory conditions of the urinary tract
- Congenital abnormalities of the urinary tract
- Pelvic radiation
- “ Nearly 2-4% of patients with bladder cancer develop upper tract TCC. Hence, the surveillance of the upper tract, in which imaging plays a central role, is an important component in the management of TCC.”
Imaging and Staging of Transitional Cell Carcinoma: Part I, Lower Urinary Tract
Vikram R et al
AJR 2009;192:1481-1487
- “ A thorough CT urography examination involves four key phases- unenhanced, arterial, nephrogenic, and excretory- to permit identification of features such as enhancement, excretion, and associated vasculature.”
Imaging of Urothelial Cancers: What the Urologist Needs to Know
Lee EK et al.
AJR 2011; 196:1249-1254
- “ A thorough CT urography examination involves four key phases- unenhanced, arterial, nephrogenic, and excretory- to permit identification of features such as enhancement, excretion, and associated vasculature.”
Imaging of Urothelial Cancers: What the Urologist Needs to Know
Lee EK et al.
AJR 2011; 196:1249-1254 - “ CT urography was more accurate than excretory urography in the detection and localization of upper urinary tract urothelial carcinoma and should be considered as the initial examination for the evaluation of patients at high risk for upper urinary tract urothelial carcinoma.”
Comparison of CT Urography and Excretory Urography in the Detection and Localization of Urothelial carcinoma of the Upper Urinary Tract
Jinzaki M et al.
AJR 2011; 196:1102-1109 - Infiltrative TCCs May Simulate: Differential Dx
- Focal infection
- Renal cell carcinoma (papillary cell as hypovascular)
- Lymphoma
- Metastases
- XGP - Urothelial Cancers: findings
- Single or multiple sessile filling defects that compress the renal sinus fat
- Pelvicaliceal irregularities (stricture like)
- Focal or diffuse mural thickening
- Caliceal amputation
- Tumor filled distended calices - Urothelial Cancers: facts
- Make up 10-15% of all renal tumors
- 90% are transitional cell carcinomas, 9% are squammous cell carcinoma and 1% are mucinous adenocarcinoma
- Average age is 6-7th decade of life
- Male to female ratio is 3-1
- 40% of patients with upper tract TCC will develop metachronous TCC of the lower urinary tract "Familiarity with the unusual radiologic features of urothelial cancer of the renal pelvicaliceal system will facilitate making the correct diagnosis as well as developing adequate treatment options."
Urothelial Cancer of the Renal Pelvicaliceal System: Unusual Imaging Manifestations
Prando A et al.
RadioGraphics 2010; 30:1553-1566"The positive predictive value of CT urography for upper tract urothelial cancer is moderate because benign findings mimic cancer. Positive findings on a CT urogram are more likely to indicate cancer in the setting of large masses or positive urine cytology."
Positive Predictive Value of CT Urography in the Evaluation of Upper Tract Urothelial Cancer
Sadow CA et al.
DOI:10.2214/AJR.09.4147"When stratified by location, urothelial thickening was more predictive of tumor in the pelvicalyceal system than in the ureter. In contrast filling defects were more predictive in the ureter than the pelvicalyceal system."
Significance of Upper Urinary Tract Urothelial Thickening and Filling Defect Seen on MDCT Urography in Patients With a History of Urothelial Neoplasms
Xu AD et al.
AJR 2010; 195: 959-965"Our data confirm that CT urography has utility in the surveillance of upper tract tumors. Urothelial thickening is an important radiologic sign of tumor, especially in the pelvicalyceal system."
Significance of Upper Urinary Tract Urothelial Thickening and Filling Defect Seen on MDCT Urography in Patients With a History of Urothelial Neoplasms
Xu AD et al.
AJR 2010; 195: 959-965- Split Bolus Technique for CT Urography (Maheshwari E et al.)
- Scan without contrast from top of kidneys thru the base of the bladder
- Inject 50 ml of iodixanol at 3 cc/sec
- Wait 5 minutes
- Inject 80 ml of iodixanol at 3 cc/sec
- Wait 100 seconds and then scan the patient from the top of the kidneys thru the pelvis (combined nephrographic and excretory phase) " In conclusion, in patients with hematuria, split bolus MDCT urography and oral hydration provide complete opacification of the majority of upper urinary tract segments and are accurate for the diagnosis of upper tract urothelial tumors."
Split-Bolus MDCT Urography: Upper Tract Opacification and Performance for Upper Tract Tumors in Patients with Hematuria
Maheshwari E et al.
AJR 2010; 194:453-458"We believe that oral hydration is a simple method of aiding urinary tract opacification while maintaining an effective workflow, as has been advocated previously by Kawamoto et al."
Split-Bolus MDCT Urography: Upper Tract Opacification and Performance for Upper Tract Tumors in Patients with Hematuria
Maheshwari E et al.
AJR 2010; 194:453-458"The negative predictive value of MDCT urography for upper tract tumors was 99.5% and 100% for two reviewers and 100% for the prospective interpretations."
Split-Bolus MDCT Urography: Upper Tract Opacification and Performance for Upper Tract Tumors in Patients with Hematuria
Maheshwari E et al.
AJR 2010; 194:453-458"Split-bolus MDCT urography provided at least 50% opacification of the majority of upper urinary tract segments and had high sensitivity, specificity, and accuracy for the detection of upper urinary tract tumors"
Split-Bolus MDCT Urography: Upper Tract Opacification and Performance for Upper Tract Tumors in Patients with Hematuria
Maheshwari E et al.
AJR 2010; 194:453-458- Split Bolus Technique for the Kidneys (Zamboni GA et al.)
- Inject 50 ml of IV contrast
- Wait 3 minutes
- Inject 100 ml of contrast at 4-6 ml/sec
- Begin acquisition 5 seconds after trigger point of 200 HU is reached
- Obtain a single acquisition Kidney: Transitional Cell Carcinoma of the Kidney: Facts
- Multiplicity common
- Distal ureter most common site in the ureter (73%)
- metastases common to renal vein, IVC and local nodes
- Tumors may occassionally have fine stippled calcificationsKidney: Transitional Cell Carcinoma of the Kidney: Facts
- 15% of malignant renal tumors
- More common in men (2-1)
- Incidences peaks in 7th decade
- Upper tract TCC occurs in 2% of patient with lower tract disease, but 40% of patients with upper tract disease develop lower tract disease"The hallmark of TCC is multiplicity and recurrence. Nearly 2-4% of patients with bladder cancer develop upper tract TCC, but 40% of patients with upper tract TCC develop bladder cancer."
Imaging and Staging of Transitional Cell Carcinoma: Part 2, Upper Urinary Tract
Vikram R et al
AJR 2009;192:1488-1493