OBJECTIVE We investigated the clinical and pathological features, and long-term followup of patients with radical nephrectomy for renal cell carcinoma of 30 mm. or smaller and a normal contralateral kidney. METHODS Between 1973 and 1993, 74 patients 29 to 83 years old (average age 60) underwent radical nephrectomy for renal cell carcinoma of 30 mm. or smaller. Average followup was 101 months (range 10 to 236). Of the 74 tumors 21 were stage pT1, 36 stage pT2 and 12 stage pT3 (all 69 stag N0 to NxM0), while 5 were stages pT1 to 3, N1 or M1. A total of 27 patients died during follow-up. Of 11 patients who died of disease progression 5 had metastatic disease initially. RESULTS Overall survival rates were 73% at 5 years, 55% at 10 years and 38% at 20 years. Cancer-specific survival rates without the 5 patients with stage N1 or M1 disease were 91% at 5 years, and 80% at 10 and 20 years. For the group with nonmultifocal renal cell carcinoma, stage NO to Nx and/or MO, the cancer-specific survival rates were 93% at 5 years, and 81% at 10 and 20 years. For the group with multifocal renal cell carcinoma, stage NO to Nx and/or MO, the cancer-specific survival rate was 75% at 5, 10, and 20 years. There was a significant survival difference between the nonmultifocal and multifocal renal cell carcinoma groups at 5 years (p<0.05) but not at 10 and 20 years. CONCLUSIONS Small renal cell carcinoma is definitively not a benign disease and a tumor of 30 mm. or smaller does not mean there is no risk of metastatic or multifocal disease.