Renal cell carcinoma: Impact of mode of detection on its pathological characteristics

Objective : Data correlating mode of presentation of renal cell carcinoma (RCC) with pathological prognostic factors is sparse from India. We compared RCC presenting incidentally with those presenting symptomatically with respect to pathological prognostic factors and assessed whether this could serve as a decision making resource for diagnosing small and more favorable tumors. Materials and Methods : The data were reviewed for 328 patients operated for renal tumors between January 2000 and October 2008 at our institute. The pathological factors (tumor size, stage, grade, histopathological type) in relation to the mode of presentation were analyzed according to 1997 TNM criteria. Statistical analysis was performed via the chi-square (Fisher exact) and Mann -Whitney U test. The statistical significance level utilized was P < 0.05. Results : Among the patients assessed, 93 (28.4%) had incidental diagnosis and 235 (71.6%) had symptomatic presentation. Sex and side distribution was not significantly different in the two groups. Mean tumor size was 5.75 +/- 2.73 cm in incidentally detected RCC (IRCC) and 9.32 +/- 3.70 (P < 0.001) in symptomatic RCC (SRCC). Stage I and II tumors were significantly greater in IRCC than SRCC (P < 0.001 and 0.005 respectively) whereas stage III and IV tumors were significantly less in IRCC than SRCC. There was a predominance of higher grade tumors in SRCC, 50% being higher grades (Fuhrman's grade III and IV) in SRCC than 28.1% in IRCC (P = 0.003). There were 4 tumors with collecting duct histology in SRCC and none in IRCC. Sarcomatoid differentiation was present in 14 and 1 patient in SRCC and IRCC respectively. Conclusion : Incidental detection of renal carcinoma as compared to symptomatic tumors is lower in India as compared to western world. Incidental tumors have significantly favorable pathological prognostic factors. Our results might form a basis for further studies on how to pick RCC at an earlier stage.