Sperm cryopreservation for fertility preservation in male patients with cancer at a single-center in Japan

Advanced treatment modalities for cancer have led to improved prognosis in patients with cancer. However, these treatments may adversely affect the fertility of these patients. Therefore, peritreatment preservation of fertility in adolescent and young adult populations is very important. For male patients, sperm cryopreservation before the initiation of treatment for cancer is currently the most effective method for the preservation of fertility. We performed a retrospective cohort analysis of a sperm cryopreservation protocol at the Yokohama City University Medical Center between 2012 and 2017. A total of 235 men were referred and attempted sperm cryopreservation during this period. The most prevalent diseases were hematological malignancies (38.7%; leukemia, malignant lymphoma, and multiple myeloma), testicular cancer (32.3%, including extragonadal germ cell tumor), bone and soft tissue sarcoma (8.5%), lung cancer (4.7%), prostate cancer (4.3%), and brain tumor (2.6%) in descending order. The median age of patients was 31 (range: 13–65) years, mean sperm density and motility were 28.54±30.25 106/mL, and 20.38±20.62%, respectively. Sperm cryopreservation was successfully performed in 195 patients (83.0%). In those with cryopreservation failure (36 patients; 15.3%), the primary causes were azoospermia or poor semen quality. In the remaining 4 patients (1.7%), testicular spermatozoa were successfully cryopreserved through surgical extraction. In the cryopreservation failure group (n=36), 23 patients (63.9%) were referred after initiation of treatment. Of those, 17 patients were referred from the departments of hematology and oncology. Moreover, sperm density was significantly lower in patients who under gone treatment than in those of the pretreatment group (P=0.003). Cryopreserved sperm from 18 patients was used in 23 in vitro fertilization cycles, resulting in a clinical pregnancy rate of 56.5% per cycle. It is important to inform other departments regarding the option for sperm cryopreservation before initiating treatment in patients with cancer.