Benign adenomatous multicystic kidney tumor (Perlmann’s tumor) and renal cortical carcinoma with adenomatous multicystic features: 12 cases

Objectives. To re-examine clear cell cystic lesions of the kidney and to assess their potential clinicopathologic significance, as the long-forgotten diagnosis of benign adenomatous multicystic kidney tumor (Perlmann’s tumor) has not been cited in the literature in more than 35 years. Methods. We identified 12 patients between 1959 and 1996 who underwent a radical nephrectomy at our institution and were diagnosed with either adenomatous multicystic clear cell kidney tumor (n = 4) or with renal cell carcinoma (RCC) associated with features of adenomatous clear cell multicystic kidney tumors (n = 8). All diagnoses were reviewed histologically by a single pathologist. Results. Nine of 12 patients had Stage T2N0M0 disease, and 3 patients had Stage T1N0M0 disease. There were 8 men and 4 women. The average age at the time of surgery was 60.5 years (range 25 to 74). Six patients are still alive with a mean follow-up of 4.7 years (range 1.5 to 16.3) and have no evidence of recurrent disease. Of the 6 patients who died, mean survival time was 8.8 years (range 0 to 15.7). One patient died in the perioperative period, and the other 5 patients died of other causes, unrelated to their kidney tumor. Conclusions. Adenomatous clear cell multicystic kidney disease may represent a histologically distinct benign neoplasm, and its presence in association with RCC may confer a more favorable prognosis. Its distinction from usual solid hemorrhagic or focally necrotic RCC is important.