Long-Term Safety of Pregnancy After Breast Cancer

According to a study, published in Annals of Surgical Treatment and Research, “long-term safety of pregnancy after breast cancer (BC) remains controversial, especially with respect to BC biological subtypes.” Researchers, led by Minsun Kang, MHS, PhD, retrospectively examined women with BC and matched control patients and reported that their observational study uncovered “reassuring evidence on the long-term safety of pregnancy in young patients with BC regardless of the BC biological subtype.”

To examine the long-term effects of pregnancy after BC, the trial evaluated 544 women with BC, 272 pregnant and 272 not pregnant, with matched characteristics. The study’s population were categorized into six subgroups based on combination of prescription therapies. Patients were followed-up for 10 years or until “disease and mortality occurrence after the diagnosis of BC.”

Dr. Kang and colleagues calculated a 10-year actuarial overall survival (OS) rate of 97.4% and 91.9% for women with pregnancy after BC and nonpregnant women, respectively. Notably, the team observed that “the pregnant group showed significantly better OS (adjusted hazard ratio [HR] = 0.29; 95% confidence interval [CI], 0.12–0.68; p = 0.005) and did not have a significantly inferior disease-free survival (HR = 1.10; 95% CI, 0.61–1.99; p = 0.760).”

The study’s authors added that outcomes were consistent between the subgroups in all analyses, and ultimately suggested that pregnancy after BC appears to have comparable long-term safety to nonpregnant patients.