Effect of improved diagnosis of renal cell carcinoma on the course of the disease.

The impact of the improved diagnosis of renal cell carcinoma (RCC) on the course of the disease was evaluated in 188 patients who were diagnosed and treated at a single medical center. Sixty-seven patients (group A) who had undergone nephrectomy between 1979 and 1983 for RCC initially diagnosed by intravenous pyelography (IVP) were compared with 121 patients (group B) who had undergone nephrectomy between 1983 and 1989, diagnosed by ultrasound and/or computed tomography (CT) scan. Incidental asymptomatic tumors were found in 18 of 67 (26.9%) group A patients and in 57 of 121 (47.1%) group B patients (P < 0.001). The incidence of small tumors of < 5 cm in diameter was significantly lower in group A compared to group B (25.4% vs. 47.9%, respectively, P < 0.01). The disease-free 5-year survival rate for group A was 40% compared to 80% for group B. It is concluded that the introduction of modern imaging techniques has improved the survival of patients with RCC and decreased the progression rate of the disease.