Aims: The authors investigated the frequencies of the various histological types of adult renal tumours.
Methods: The slides of 469 nephrectomies performed in the Department of Urology, Szeged University between 1990 and 2003 were revised according to the 1997 Heidelberg and 2004 WHO classification schemes.
Results: 86.7% of all the tumours (n = 407) were malignant. Among the malignant tumours, the frequency of renal cell carcinomas was 91.1% (n = 371). 88.4% of the renal cell carcinomas (n = 328) were of conventional type, 5.6% (n = 21) were papillary and 4% (n = 15) were chromophobe. The authors observed 3 Bellini duct, 1 mucinous tubular and 3 non-classifiable carcinomas, with a combined incidence of 1.8%. 84.5% of the conventional carcinomas were clear cell (n = 277), 8.8% were eosinophilic granular (n = 29), 3.9% were multilocular cystic (n = 13) and 2.7% were sarcomatoid carcinomas (n = 9). The median age of the patients with conventional carcinoma was 60 (median, range: 25-84), in the papillary group it was 62 (43-78), and in the chromophobe group was 59 (17-77). The median age of patients affected by transitional cell carcinoma was 64 (range: 45-81). As far as benign tumours are concerned (13.2%, n = 62), oncocytomas (n = 37, 7.8% of all the tumours) affected mainly females, whereas angiomyolipomas (n = 21, 4.4% of all the tumours) occurred in females only. In 13 oncocytoma cases, the tumours were initially diagnosed as malignant.
Conclusions: Adult malignant renal tumours affect mainly patients around the age of 60. The commonest diagnosis was clear cell carcinoma of conventional type. The incidence of clear cell carcinoma was 5% higher than that reported in the literature (84.5% vs 70-80%) whereas that of papillary carcinoma was 5% lower (5% vs 10-15%). In comparison with the literature data, oncocytomas were relatively common (8% instead of 3%), and not rarely, it was difficult to distinguish them from renal cell carcinomas.