CLINICOPATHOLOGICAL STUDY OF 97 CASES OF SMALL RENAL-CELL CARCINOMAS USING DNA FLOW CYTOMETRIC ANALYSES

The incidence of small renal cell carcinomas (RCC) has increased recen tly as diagnostic imaging techniques have improved. The indications fo r partial nephrectomy for small RCC confined to the kidney are still c ontroversial. Ninety-seven small RCC 2.5 cm or smaller, including inci dental, occult, and dialysis associated carcinomas obtained at surgery or autopsy were examined. Various clinicopathologic parameters were a ssessed and survival was analyzed using the Kaplan-Meir method. Sevent y-eight cases were incidental carcinomas. Carcinomas caused death in f ive cases, four of which had initial signs of metastatic disease. Diff erences in survival between patients with expansive and invasive (inte rmediate and infiltrating) growth patterns, solid and other structural patterns, clear and other cell types, grade 1 and higher grades of nu clear atypia, and with and without lymph node metastasis were statisti cally significant. All surgical cases were alive except one who died o f another disease. Poor prognostic factors seen in five fatal autopsy cases included invasive growth pattern, solid structural pattern, spin dle cells, grade 3 nuclear atypia, and Bellini duct carcinoma. Small R CC may be treated with partial nephrectomy provided they do not show t hese features, although there is low risk of recurrence or development of de novo cancer.