Diagnostic strategy in renal mass lesions

During a period of 8 years 169 patients were evaluated for a possible malignant renal mass lesion according to a uniform but individualized strategy. Intravenous urography (IVU), ultrasound, and guided fine needle aspiration (FNA) were performed in all patients. CT was added only in the presence of diagnostic uncertainty, and angiography only prior to preserving surgery. In 121 patients (72%) therapeutic decision was based on IVU, ultrasound, and cytology alone. CT was considered necessary in 32 patients (19%). A correct cytological diagnosis was obtained in 86.9%, the sensitivity was 86.8%, and the specificity 87.5%. A false positive cytological result in 4 instances and 17 false negative results did not mislead the therapeutic decision-making, since they were all identified as probable false because of clinical evidence or the results of the imaging studies. A tentative histological diagnosis is frequently possible (e.g. poorly differentiated clear cell carcinoma, urothelial carcinoma). It is concluded that a restricted and individualized strategy based primarily on ultrasound and FNA is feasible with the need of CT in a minority of patients.