DEOXYRIBONUCLEIC-ACID FLOW-CYTOMETRY OF TESTICULAR LEYDIG-CELL TUMORS

We analyzed by flow cytometry the deoxyribonucleic acid content of 13 paraffin embedded, formalin-fixed Leydig cell tumors of the testis. Of the tumors 10 were clinically benign (9 diploid and 1 aneuploid) and 3 were malignant (aneuploid) The benign aneuploid tumor showed moderat e cellular atypia and a low mitotic count (less than 2 per 10 high pow er fields). Our study suggests that the majority of Leydig cell tumors are diploid and the less common malignant tumors are typically aneupl oid, and that deoxyribonucleic acid flow cytometric findings can be us eful as a prognostic indicator in these tumors.