Survival Significantly Lower for Children and Young Adults With Second Cancers

Second primary malignant neoplasms (SPMs) are a well-known late effect after cancer, and a new study has found that they are more deadly among children and young adults than older adults.

A comparison of 15,954 pediatric, 125,750 adolescent and young adult (AYA), and 878,370 older adult patients with 14 cancers occurring as an SPM or primary malignant neoplasm (PM) found that 5-year survival after an SPM was 20% lower for AYAs and 33% lower for children. Survival was only 8% lower for older adults compared with a PM at the same age. The study was published in JAMA Oncology.

“It is possible that the detrimental effect of SPMs on survival accounts for some of the lack of survival improvement in AYAs compared with pediatric and older patients with cancer,” the authors wrote.

They used data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program. Survival rates of patients with SPMs were compared with their corresponding first primary cancer type. The study included 14 common AYA cancers: female breast cancer; thyroid, melanoma, and testicular cancers; Hodgkin lymphoma; non-Hodgkin lymphoma; acute lymphoid leukemia, acute myeloid leukemia; soft-tissue sarcoma; bone sarcoma; and colorectal, central nervous system, cervical, and ovarian cancers.

The results found that children with acute lymphoid leukemia, acute myeloid leukemia, and central nervous system cancer as an SPM had a higher risk of death than when those cancers occurred as a PM. For AYAs, Hodgkin lymphoma and thyroid cancer had a 3-fold increased risk of death.

The researchers determined that the impact of an SPM on survival was most pronounced among AYAs. Although relatively few SPMs occur in children, they too were more greatly affected than older adults.

The lack of treatment information, comorbidities, health behaviors, and genetic information were noted as study limitations.

“As more young patients with cancer continue to live for many decades as survivors, the impact of a particular diagnosis on survival may inform age-specific prevention, screening, treatment, and survivorship, recommendations,” the authors concluded.