Table 3.

Impacts of cancer treatment on gonadal function by sex and treatment modality

Impacts in female patients
Surgery	Ovarian and other pelvic organ surgery may reduce the number of ovarian follicles (each of which is a cellular aggregation containing an immature oocyte surrounded by its encasing cells, such as granulosa cells and theca cells; the maturation of follicles is associated with the maturation of oocytes) and suppress ovarian sex hormone production, leading to ovarian failure
Chemotherapy	Many anticancer agents inhibit the growth of ovarian follicles, causing temporary, i.e., reversible, amenorrhea. On the other hand, alkylating agents (e.g., cyclophosphamide and busulfan) and platinum analogs (e.g., cisplatin) are highly gonadotoxic and can reduce the number of oocytes. Treatment with any such agent at a high cumulative dose can cause permanent loss of oocytes soon after treatment and reduce ovarian hormone production
Radiotherapy	Ovarian radiation can reduce the number of oocytes and impair ovarian function. Radiation at a high cumulative dose can cause permanent loss of oocytes soon after treatment and reduce ovarian hormone production. Hypothalamic or pituitary radiation may impair ovulation
Impacts in males
Surgery	Testicular surgery may interfere with spermatogenesis, testicular hormone production, and spermatozoa transportation, leading to testicular failure
Chemotherapy	Alkylating agents (e.g., cyclophosphamide, ifosfamide, busulfan, and procarbazine) reduce the number of spermatogonia. Treatment with any such agent at a high cumulative dose can cause permanent impairment of spermatogenesis soon after treatment
Radiotherapy	Testicular radiation can reduce the number of spermatogonia. Radiation at a high cumulative dose can cause permanent impairment of spermatogenesis soon after treatment. Hypothalamic or pituitary radiation may impair spermatogenesis and/or hormone production
Impacts in both sexes
Interferon-α and tyrosine kinase inhibitors can induce thyroid function abnormalities