Risk factors of Second Malignant Neoplasms in Childhood Cancer Survivors

Cancer is as the second leading cause of death among children in the United States. The mortality rate for cancer has witnessed a decline, dropping from 6.5 per 100,000 in 1970 to 2.3 per 100,000 in 2016. Second malignant neoplasms (SMNs) represent novel primary malignancies emerging after the initial cancer diagnosis, particularly prominent as late effects of cancer therapy in children. The incidence of SMNs sees a substantial increase over time, reaching nearly 10% even a decade after the initial diagnosis. A comparative analysis between the general population and child cancer survivors reveals a six-fold higher risk of developing SMNs among the latter. Various factors contribute to the elevated risk of second cancers, with age, lifestyle, environmental influences, primary cancer treatment, and genetic predisposition playing pivotal roles. Noteworthy risk factors for SMNs in children encompass radiation therapy, chemotherapeutic agents, topoisomerase inhibitors, genetic factors, hematopoietic stem cell transplantation, and ionizing radiation, as elucidated in the present study. Despite these findings, further research is imperative to accurately quantify the risks associated with etiological factors, enabling the identification of individuals at a heightened risk for second cancers and facilitating proactive screening and preventive measures.