Background: Children who receive high-dose radiotherapy to the hypothalamic-pituitary (H-P) axis may be at risk for both early and late puberty. To the authors' knowledge, data regarding the risk of altered timing of menarche after higher dose radiotherapy (RT), as used in the treatment of central nervous system (CNS) tumors, are limited.
Methods: The authors evaluated 235 female survivors of CNS tumors, diagnosed between 1970 and 1986, and >1000 sibling controls who were participants in the Childhood Cancer Survivor Study, and provided self-reported data concerning age at menarche.
Results: Survivors of CNS tumors were more likely to have onset of menarche before age 10 years compared with their siblings (11.9% vs 1.0%) (odds ratio [OR], 14.1; 95% confidence interval [95% CI], 7.0-30.9). Of the 138 survivors who received RT to the H-P axis, 20 (14.5%) had onset of menarche before age 10 years, compared with 4.3% of those who did not receive RT (OR, 3.8; 95% CI, 1.2-16.5). Age <or=4 years at the time of diagnosis was associated with an increased risk (OR, 4.0; 95% CI, 1.7-10.0) of early menarche. In addition, survivors of CNS tumors were more likely than siblings to have onset of menarche after age 16 years (10.6% vs 1.9%) (OR, 6.6; 95% CI, 3.4-11.4). Doses of RT to the H-P axis >50 gray OR, 9.0; 95% CI, 2.3-59.5) and spinal RT conferred an increased risk of late menarche, as did older age (>10 years) at the time of diagnosis (OR, 3.0; 95% CI, 1.3-7.0).
Conclusions: Survivors of CNS tumors are at a significantly increased risk of both early and late menarche associated with RT exposure and age at treatment.
(c) 2009 American Cancer Society.