Preservation of fertility of adult male cancer patients treated with chemotherapy.

Chemotherapy-induced gonadal dysfunction resulting in transient or persistent infertility depends on the type of drugs and cumulative dose, and it is an important long-term complication, especially for adolescent and young adult (AYA) cancer patients. Due to its importance, a clinical practice guideline for fertility preservation in childhood and AYA cancer patients was published by the Japan Society of Clinical Oncology (JSCO) in 2017. Although the precise mechanisms remain unclear, several studies reported that the cancer itself, not the cancer treatment, adversely affected semen quality. It is reported that that poor pretreatment semen quality is commonly seen in various cancer types including testicular cancer, leukemia, brain tumor, and sarcoma. Fortunately, however, even men with poor sperm quality can be candidates for sperm cryopreservation due to recent advances in assisted reproductive technology (ART) and sperm banking techniques. Therefore, the JSCO guideline and others recommend that sperm cryopreservation should be considered as early as possible when patients are planning to undergo treatment that may render them infertile. The previous studies showed that testicular cancer and hematological tumors are the two leading types of cancer among patients who requested sperm cryopreservation. This is followed by bone and soft-tissue tumors and central nervous system tumors and others. Although the efficacy of postchemotherapy testicular sperm extraction (TESE)/intracytoplasmic sperm injection (ICSI) was reported recently, it is quite important to inform patients of the potential risk of treatment-induced infertility and the possibility of fertility preservation by sperm cryopreservation before chemotherapy.