日本における小児・AYA世代がん患者の男性妊孕性温存――一般小児科医の重要な役割

Male Fertility Preservation for Childhood and AYA Cancer Patients in Japan：The Crucial Role of General Pediatricians

小児・AYA世代がん治療の成績向上に伴い，長期生存を見据えた妊孕性温存（がん生殖医療）が重要課題となっている．本稿では，男性妊孕性の特徴と一般小児科医の役割について概説する．男児の妊孕性温存の可否は二次性徴の発来が分岐点であり，思春期以降は精子凍結が第1選択となるが，思春期前男児における精巣組織凍結はいまだ実験的段階にある．実臨床においては，採精に伴う心理的・倫理的配慮や，公的助成・全国登録システムを活用した連携が不可欠である．一般小児科医には，治療開始前の限られた時間のなかで将来のリスクに早期に気づき，遅滞なく専門施設へつなぐという，患者の希望を守る最初の介入者としてのきわめて重要な役割が求められる．

With improved survival rates in childhood, adolescent, and young adult（AYA）cancers, fertility preservation（oncofertility）has emerged as a critical priority for long-term survivors. This article outlines male-specific fertility preservation strategies and the essential role of the general pediatrician. Puberty serves as a critical milestone dictating preservation options：whereas sperm cryopreservation is the standard of care for postpubertal patients, testicular tissue cryopreservation for prepubertal boys remains experimental. In clinical practice, navigating the psychological and ethical complexities of semen collection, as well as leveraging public subsidies and national registries, is imperative. General pediatricians serve as the crucial first point of contact in protecting patients’ future fertility potential. It is incumbent upon them to identify fertility risks early and expedite referrals to specialized facilities within the narrow window prior to the initiation of gonadotoxic treatment.