RESUMO
OBJECTIVE: To estimate the effect of platinum-based chemotherapy on live birth (LB) and infertility after cancer, in order to address a lack of treatment-specific fertility risks for female survivors of adolescent and young adult cancer, which limits counseling on fertility preservation decisions. DESIGN: Retrospective cohort study. SETTING: US administrative database. PATIENTS: We identified incident breast, colorectal, and ovarian cancer cases in females aged 15-39 years who received platinum-based chemotherapy or no chemotherapy and matched them to females without cancer. INTERVENTION: Platinum-based chemotherapy. MAIN OUTCOME MEASURES: We estimated the effect of chemotherapy on the incidence of LB and infertility after cancer, overall, and after accounting for competing events (recurrence, death, and sterilizing surgeries). RESULTS: There were 1,287 survivors in the chemotherapy group, 3,192 in the no chemotherapy group, and 34,147 women in the no cancer group, with a mean age of 33 years. Accounting for competing events, the overall 5-year LB incidence was lower in the chemotherapy group (3.9%) vs. the no chemotherapy group (6.4%). Adjusted relative risks vs. no chemotherapy and no cancer groups were 0.61 (95% confidence interval [CI] 0.42-0.82) and 0.70 (95% CI 0.51-0.93), respectively. The overall 5-year infertility incidence was similar in the chemotherapy group (21.8%) compared with the no chemotherapy group (20.7%). The adjusted relative risks vs. no chemotherapy and no cancer groups were 1.05 (95% CI 0.97-1.15) and 1.42 (95% CI 1.31-1.53), respectively. CONCLUSIONS: Cancer survivors treated with platinum-based chemotherapy experienced modestly increased adverse fertility outcomes. The estimated effects of platinum-based chemotherapy were affected by competing events, suggesting the importance of this analytic approach for interpretations that ultimately inform clinical fertility preservation decisions.
