Does motherhood increase the risk of developing subsequent malignant neoplasms after childhood cancer treatment?

Abstract

BACKGROUND: Most young women who have survived childhood cancer express a desire to have children. Many of them are concerned about the potential adverse impact of pregnancy on their health, which has been affected by prior cancer treatment. The aim of this study was to determine whether motherhood increases the risk of developing subsequent malignant neoplasms. METHODS: The study cohort consisted of 942 female childhood cancer survivors, median age at first cancer diagnosis 10.84 years (IQR 4.29-14.92), who had been treated at the Department of Pediatric Hematology and Oncology, Motol University Hospital, Prague, between 1965 and 2018. In this group, 363 women gave birth to 559 children. RESULTS: Seventy-three female childhood cancer survivors developed 80 subsequent malignant neoplasms. Of these, 40 subsequent malignant neoplasms occurred in women who had children. The median time from the end of primary cancer treatment to first subsequent malignant neoplasm development was 19.93 years (IQR 14.55-26.56). A comprehensive analysis revealed no difference in the risk of subsequent malignant neoplasms between mothers and "non-mothers". Only older age of the cancer survivors in follow-up and previous radiotherapy (p = 0.0133) were significant risk factors for subsequent malignant neoplasm development. CONCLUSIONS: This study revealed that motherhood does not increase the risk of subsequent malignant neoplasms. We confirmed a statistically significant increased risk of subsequent malignant neoplasms only for previous treatment modality, the length of follow-up and the age of the female childhood cancer survivors. These results are important for improving the quality of life of young cured women who are worried about a planned pregnancy. PLAIN LANGUAGE SUMMARY: This study evaluated the long-term cancer risk among women treated for cancer during childhood, with particular focus on those who later gave birth. Among 942 participants, 363 had post-treatment pregnancies. Results indicate that childbearing does not increase the risk of subsequent malignant neoplasms in this population. Instead, elevated risk for subsequent malignant neoplasms was associated with older age at follow-up and prior exposure to radiotherapy. These findings provide evidence that pregnancy is safe for female childhood cancer survivors and support informed reproductive decision-making.