Treatments and Mortality Among Female Childhood Cancer Survivors With Subsequent Breast Cancer

By: Chris Schimpf, BS
Posted: Tuesday, July 23, 2024

Lucie Marie Turcotte, MD, MPH, MS, of the University of Minnesota Medical School, Minneapolis, and colleagues found that childhood cancer survivors with subsequent breast cancer generally receive guideline-concordant breast cancer treatment that differs from patients with primary breast cancer, and they do not appear to experience higher rates of on-therapy treatment modifications. However, they may suffer significantly higher mortality, primarily driven by other health conditions. The investigators presented their findings at the 2024 American Society for Clinical Oncology (ASCO) Annual Meeting (Abstract 10026), stressing that managing comorbidities is critical to improving long-term survival for this high-risk population.

A total of 431 female survivors of childhood cancer diagnosed with subsequent breast cancers between 1981 and 2016 were included in the study, drawn from the CCSS (Childhood Cancer Survivor Study). They were matched on a 1:1 basis by demographics, diagnosis age/year, and breast cancer characteristics with a multi-institutional sample of female patients diagnosed with primary breast cancer (n = 688).

The investigators reported that 77% of subsequent breast cancers were invasive, with hormone receptor profiles similar to that of the general population (78% estrogen receptor–positive, 26% HER2-positive). They found that guideline-concordant breast cancer treatment did not differ between childhood cancer survivors and patients diagnosed with primary breast cancer (94% vs 93%), but treatment selection differed based on the complex clinical histories of the cancer survivors and multiple treatment options.

Among patients treated with surgery and chemotherapy, childhood cancer survivors did not have a greater likelihood of dose reductions or omissions, treatment delays, or hospitalization for fever and neutropenia, but they were more likely to experience hematologic toxicities (21% vs 9%; P = .033) and other organ system–specific toxicities (36% vs 11%; P < .001). They also reported that survivors experienced “strikingly higher” all-cause mortality, especially after in situ disease. Breast cancer accounted for 51% of deaths among cancer survivors with invasive disease, followed by other subsequent malignancies (15%) and cardiovascular diseases (15%).

Disclosure: Dr. Turcotte reported no conflicts of interest. For full disclosures of the other study authors, visit coi.asco.org.

2024 ASCO Annual Meeting

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