Incidence and detection of testicular leukemia in children1
The current treatment of acute lymphocytic leukemia in children continues to result in improved survival statistics. Unfortunately, some children who appear to be free of disease show a relapse because of an apparent propensity of leukemic cells to infiltrate the testis and resist conventional therapy. In an effort to detect subclinical testicular leukemia, 14 males with acute lymphocytic leukemia achieving 36 months of continuous complete remission due to protocol chemotherapy underwent routine bilateral testis biopsy immediately prior to the planned cessation of maintenance chemotherapy. Biopsy findings determined the need for testicular irradiation and reinduction of systemic chemotherapy. Thirteen patients had palpably normal testes at the time of biopsy and no histologic evidence of leukemic testicular infiltration. One patient had a normal right testis and a firm left testis with bilateral leukemic involvement as shown by the biopsy results. This represents a 7.1% incidence of occult testicular leukemia. Theoretic considerations of leukemic infiltration of the testis and the improved prognosis of patients treated for residual or persistent testicular disease suggest the need for a reliable method to detect testicular leukemia. This experience with routine testicular biopsy of palpably normal testes and with biopsy of palpably abnormal testes with testicular infiltration in patients still undergoing chemotherapy suggests that physical examination alone is a reliable method to detect leukemic testicular infiltration in most patients. Nevertheless, continued routine biopsy immediately prior to cessation of maintenance chemotherapy is still recommended to ensure that patients with occult testicular leukemia are identified.