Childbirth and fertility preservation in childhood and adolescent cancer patients: a second national survey of Japanese pediatric endocrinologists

The incidence of childhood cancer is estimated as 2,000 to 2,500 cases per year in Japan. Because of improvements in the treatment and prognosis of cancer, the number of childhood and adolescent cancer survivors has increased (1). A significant proportion of survivors experience chronic health problems that result from cancer, its treatment, or both (2,3,4). The Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers, issued by the Children’s Oncology Group, are recognized resources for healthcare professionals who provide ongoing care to survivors of pediatric malignancies (5). Endocrine disorders are major problems that can occur after the cancer treatment is over (6, 7). Thus, the Japanese Society for Pediatric Endocrinology (JSPE) issued a follow-up guide in 2011, with a minor revision in 2016, regarding childhood cancer survivor (CCS) care with the aim of ensuring all physicians involved in clinical practice undertake medical examinations for endocrine disorders (8). Chemotherapy, radiation therapy, and surgery may damage gonadal function in patients with malignant and non-malignant diseases (9,10,11,12). In 2013, the American Society of Clinical Oncology (ASCO) revised its guidelines for healthcare providers regarding fertility preservation in adults and children with cancer (13). Even though gonadal dysfunction, subfertility, and premature ovarian insufficiency (POI) have been recognized as important late effects in CCSs (14), few surveys on this topic have been conducted in Japan (15,16,17,18). Most CCSs in Japan do not receive outpatient follow-up care as adults, resulting in no data on their long-term prognosis. Therefore, we conducted a survey to reveal the current clinical practice among pediatric endocrinologists in order to investigate issues and unmet needs associated with gonadal function or fertility in CCSs (19). We subsequently conducted a second questionnaire survey to elucidate issues regarding childbirth and fertility preservation in CCSs; this survey was based on the practical experience of Japanese pediatric endocrinologists.