Childhood cancer survivors have increased risk of breast cancer, especially after >20Gy chest radiotherapy. For other risk factors evidence is inconclusive or imprecise. The International Guideline Harmonization Group (IGHG) formulated breast cancer surveillance recommendations for childhood cancer survivors based on evidence summaries and expert knowledge, and identified knowledge gaps. Research was recommended on risk by certain radiotherapy regimens, chemotherapy-drugs, age >50 years, hormone supplementation, and genetic predisposition, which cannot by addressed with sufficient precision by single study groups. Therefore, we will conduct Individual Patient Data (IPD) analyses, using the unique resource of joint data from eight large U.S and European childhood cancer survivor cohorts with availability of individual cancer treatments. During my PhD, I will address the following three clinically-relevant questions on 1) prescribed radiation dose <20 Gy and radiation fields, 2) role of specific anthracycline agents, and 3) relative and excess risk across the lifespan, especially beyond age 50 years. Meanwhile, I also work on a systematic review to examine the occurrence of subsequent breast cancer among males with a history of childhood cancer, and describe characteristics of male breast cancer patients in a large pan-European cohort of childhood cancer survivors.
Supervisor(s): Leontien Kremer, Cécile Ronckers, Jop Teepen, Flora van Leeuwen (Netherlands Cancer Institute).