Introduction Older patients with epithelial ovarian, fallopian tube, and primary peritoneal cancer (EOC) are often not offered potentially curative treatments, which can result in worse oncologic outcomes. We explored the difference in chemotherapy completion rate and reasons for discontinuation between older (≥70 years) and younger (< 70 years) patients with EOC.

Methods This retrospective cohort study was conducted in patients with EOC at King Chulalongkorn Memorial Hospital, Thailand, from January 2009 to June 2021. The association between younger/older patients with chemotherapy early discontinuationwas examined with Multivariable logistic regression analysis. The reasons for chemotherapy discontinuation were collected.

Results Among 757 EOC patients, 108 were older, and 649 were younger. The chemotherapy completion rate was lower in older than younger patients, with a statistically significant (84.3% vs. 92.6%, p=0.007). Regardless of discontinuation due to disease progression, the completion rate was comparable in both groups (93.5 vs. 95.7%, p=0.456). Dose reduction and grade 3–4 hematotoxicity were more often in the elderly group. The univariable logistic regression model showed that older age (≥70 years) was significantly associated with early chemotherapydiscontinuation (OR 2.39; 95%CI 1.29, 4.24). However, after adjusting for potential confounders, age did not significantly associate with the early discontinuation (aOR 1.20; 95%CI 0.54,2.66). Multiple comorbidities and types of surgery were identified as independent factors of the chemotherapy discontinuation.

Conclusion/Implications It is feasible for chemotherapy completion in older adults with EOC. Age only is not the determinant of chemotherapy completion. Comorbidity and disease status are crucial in determining chemotherapy discontinuation.