Purpose Childhood cancer survivors are at increased risk of developing subsequent malignant neoplasms (SMNs). We compared survival and clinical characteristics of survivors with SMNs (sarcoma, breast cancer, or melanoma) and a populationbased sample of similar frst malignant neoplasm (FMN) patients. Methods We assembled three case series of solid SMNs observed in a cohort of 5-year Dutch childhood cancer survivors diagnosed 1963–2001 and followed until 2014: sarcoma (n=45), female breast cancer (n=41), and melanoma (n=17). Each SMN patient was sex-, age-, and calendar year-matched to 10 FMN patients in the population-based Netherlands Cancer Registry. We compared clinical and histopathological characteristics by Fisher’s exact tests and survival by multivariable Cox regression and competing risk regression analyses. Results Among sarcoma-SMN patients, overall survival [hazard ratio (HR) 1.88, 95% confdence interval (CI) 1.23–2.87] and sarcoma-specifc mortality (HR 1.91, 95% CI 1.16–3.13) were signifcantly worse compared to sarcoma-FMN patients (foremost for soft-tissue sarcoma), with 15-year survival rates of 30.8% and 61.6%, respectively. Overall survival did not signifcantly difer for breast-SMN versus breast-FMN patients (HR 1.14, 95% CI 0.54–2.37), nor for melanoma-SMN versus melanoma-FMN patients (HR 0.71, 95% CI 0.10–5.00). No signifcant diferences in tumor characteristics were observed between breast-SMN and breast-FMN patients. Breast-SMN patients were treated more often with mastectomy without radiotherapy/chemotherapy compared to breast-FMN patients (17.1% vs. 5.6%). Conclusions Survival of sarcoma-SMN patients is worse than sarcoma-FMN patients. Although survival and tumor characteristics appear similar for breast-SMN and breast-FMN patients, treatment difers; breast-SMN patients less often receive breast-conserving therapy. Larger studies are necessary to substantiate these exploratory fndings.

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Keywords Childhood cancer survivors · Subsequent malignant neoplasm · Survival · Epidemiology · Long-term complications
Persistent URL dx.doi.org/10.1007/s10552-019-01204-z, hdl.handle.net/1765/119444
Journal Cancer Causes & Control: an international journal of studies of cancer in human populations
Teepen, J.C., Kremer, L.C.M, te Loo, M., Tissing, W.J., van der Pal, H.J, van den Heuvel-Eibrink, M.M, … Rutgers, EJT. (2019). Clinical characteristics and survival patterns of subsequent sarcoma, breast cancer, and melanoma after childhood cancer in the DCOG-LATER cohort. Cancer Causes & Control: an international journal of studies of cancer in human populations, 30(9), 909–922. doi:10.1007/s10552-019-01204-z