Increase in Incidental Renal Cell Carcinoma in the Northern Part of the Netherlands

Objectives: Evaluating in a retrospective survey the incidence of incidental and symptomatic renal cell carcinoma (RCC) between 1977 and 1994 in the northern part of the Netherlands and the mode of their detection. Patients and Methods: Retrospectively, 173 patients surgically treated for RCC were divided into two groups according to the period of detection, 1977–1987 (n = 87) and 1987–1994 (n = 86). Because of the increase in abdominal ultrasound in 1987, this year was used as the cutoff date. In both periods the patients were grouped according to whether the tumor was found incidentally or whether the tumor was suspected. The mode of detection was recorded together with the tumor stage at presentation and survival. Results: The incidental detection rate was 33% (29/87) in the 1977–1987 group and 49% (42/86) in the 1987–1994 group, showing a significant difference (p = 0.038). In the 1977–1987 group incidental tumors were detected with ultrasound in 83% and symptomatic tumors with ultrasound in 36%. Of the cases in the 1987–1994 group this percentage was 91 and 43%, respectively. Disease–free survival rates after a mean follow–up of 10 years were 63% in the incidental RCC group and 37% in the symptomatic RCC group (p = 0.0159). Conclusions: There is an increase in incidental tumors in this part of the Netherlands with ultrasound as the mode of detection. The disease–free survival is significantly better in the incidental tumor group.