Abdom Imaging 27:629-636 (2002).
Curry NS.
The increased use and refinement of cross-sectional imaging over the past two decades has resulted in the routine discovery of small renal lesions (<3 cm in diameter) [1-7]. Statistically, most of these are cysts, but incidental renal cell carcinoma (RCC) has been found in 0.3% of computed tomographic (CT) examinations [8] and one-third of surgically treated RCCs has been discovered incidentally [9]. This increase in identification of small lesions, primarily from the widespread use of sonography and CT, parallels increases in the incidence of RCC and the survival rate for this disease [10]. Intervention at an earlier stage of disease has improved outcome, with 5-year overall survival rate for renal cancer increasing from 45% in 1970-1973 to 61% in 1989-1996 [11, 12]. The argument has been made that lead time and length bias at least partly account for the improvement in these statistics [13]. The fact that the staging and clinical course of larger, symptomatic tumors has not changed appreciably in the past 40 years, however, suggests a real benefit from identifying and treating small masses [14]. The radiologist plays an extremely important role in identifying these lesions and characterizing them with the use of state-of-the-art equipment and meticulous imaging techniques.