RAD9A and childhood malignant neoplasm: Based on our previous expression studies (Weis et al., 2011[73]), here we investigated the epimutation rate of RAD9A in a unique cohort, consisting of fibroblasts derived from individuals who survived childhood cancer and subsequently developed a second primary cancer (2N) and matched (first tumor, manifestation age, sex) individuals with childhood cancer but without second cancer (1N).