[Show abstract][Hide abstract] ABSTRACT: CNS tumors are the most common second primary neoplasm (SPN) observed after childhood cancer in Britain, but the relationship of risk to doses of previous radiotherapy and chemotherapy is uncertain.
The British Childhood Cancer Survivor Study is a national, population-based, cohort study of 17,980 individuals surviving at least 5 years after diagnosis of childhood cancer. Linkage to national, population-based cancer registries identified 247 SPNs of the CNS. Cohort and nested case-control studies were undertaken.
There were 137 meningiomas, 73 gliomas, and 37 other CNS neoplasms included in the analysis. The risk of meningioma increased strongly, linearly, and independently with each of dose of radiation to meningeal tissue and dose of intrathecal methotrexate. Those whose meningeal tissue received 0.01 to 9.99, 10.00 to 19.99, 20.00 to 29.99, 30.00 to 39.99 and≥40 Gy had risks that were two-fold, eight-fold, 52-fold, 568-fold, and 479-fold, respectively, the risks experienced by those whose meningeal tissue was unexposed. The risk of meningioma among individuals receiving 1 to 39,40 to 69, and at least 70 mg/m2 of intrathecal methotrexate was 15-fold, 11-fold, and 36-fold, respectively, the risk experienced by those unexposed. The standardized incidence ratio for gliomas was 10.8 (95% CI, 8.5 to 13.6). The risk of glioma/primitive neuroectodermal tumors increased linearly with dose of radiation, and those who had CNS tissue exposed to at least 40 Gy experienced a risk four-fold that experienced by those who had CNS tissue unexposed.
The largest-ever study, to our knowledge, of CNS tumors in survivors of childhood cancer indicates that the risk of meningioma increases rapidly with increased dose of radiation to meningeal tissue and with increased dose of intrathecal methotrexate.
Journal of Clinical Oncology 11/2010; 28(36):5287-93. · 18.04 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Previous studies have reported substantially increased risks of breast cancer among survivors of childhood cancer at 10-20 years posttreatment. Whether these excess risks are sustained beyond 40 years of age when general population incidence of breast cancer begins its steep increase is largely unknown. We quantified the risk of breast cancer in adult female survivors with considerably more survivors followed-up beyond 40 years of age than previously available. Standardized Incidence Ratios (SIR), Excess Absolute Risks (EAR), and cumulative incidence were calculated within a population-based cohort of 8,093 female survivors of childhood cancer. Poisson regression models were used to model SIRs and EARs in a multivariable setting. Eighty-one survivors developed a primary breast cancer, where 37.5 were expected (SIR= 2.2, 95% CI: 1.7-2.7). SIRs decreased significantly with increasing attained age (p(trend) < 0.001) to an SIR of 0.9 (95% CI: 0.5-1.8) at ages beyond 50 years; EARs increased significantly to about 40 years of age (p(trend) < 0.001) but then plateau. Between 30 and 49 years of age survivors experienced approximately 1 extra breast cancer per 1,000 survivors per year. Overall, 3% developed breast cancer by the age of 50. The substantially increased relative risks of breast cancer observed at 10-20 years postdiagnosis are not sustained into ages at which the risk of breast cancer in the general population becomes substantial. Among women who survived to an age of at least 50 years there is currently no evidence of an increased risk of breast cancer.
International Journal of Cancer 11/2008; 123(9):2156-63. · 6.20 Impact Factor