Long-term endocrine side effects of childhood Hodgkin's lymphoma treatment: a review

BACKGROUND Since childhood cancer survival has increased, long-term effects of treatment have gained interest. Childhood Hodgkin's lymphoma has been treated successfully for decades now. We provide an overview of the literature on long-term endocrine side effects, such as gonadal dysfunction and growth retardation, as a result of childhood Hodgkin's lymphoma treatment. METHODS A comprehensive search of the Pubmed database was performed. RESULTS We identified 16 studies (10 studies: 298 male survivors and 6 studies: 230 female survivors) about gonadal dysfunction. In survivors treated with alkylating agents or pelvic radiotherapy, severe gonadal damage is described. Recovery was rarely described. Seven studies (481 survivors) about bone mineral density (BMD) and growth were identified. The effects on BMD appear to be small. Data on growth are scarce, but show that radiotherapy in a dose of >30 Gy including the spine, especially in pre-pubertal children, results in reduced height. We included 10 studies (4012 survivors) about thyroid complications. Hypothyroidism is the most common thyroid disorder after radiotherapy. There is also a significant incidence in thyroid carcinoma after low-dose radiation. In survivors treated with chemotherapy only, hypothyroidism and thyroid cancer have not been reported. CONCLUSIONS The severity of endocrine toxicity after childhood Hodgkin's lymphoma depends on the type of treatment. Gonadal dysfunction seems to be the most severe endocrine long-term effect, especially after treatment with alkylating agents or pelvic radiotherapy. The knowledge obtained in specific follow-up programmes for paediatric cancer survivors will help to find the optimal balance between curability and long-term side effects.