NATIONAL HARBOR, MD. – A large retrospective database study linked the use of vaginal brachytherapy and chemotherapy with improved survival among patients with early-stage uterine papillary serous carcinoma.
The findings offer a degree of clinical guidance on the adjuvant treatment of this relatively rare, aggressive histologic cancer subtype, Stephanie Cham, MD, said during a video interview at the annual meeting of the Society of Gynecologic Oncology.
Large dataset analyses can be especially helpful for exploring the treatment of rare diseases for which clinical trials can be infeasible, said Dr. Cham of Columbia University College of Physicians and Surgeons in New York. To evaluate chemotherapy, vaginal brachytherapy, and whole beam pelvic radiation therapy in stage I and stage II uterine papillary serous carcinoma, she and her associates analyzed the National Cancer Database.
Among 7,325 patients treated between 1998 and 2012, 38% of patients had received chemotherapy, 18% had received external beam radiation, and 20% received brachytherapy, Dr. Cham said. The use of chemotherapy rose significantly over time, regardless of stage (P less than .0001), as did the use of brachytherapy, while the use of external beam radiation decreased.
After the researchers controlled for numerous demographic and clinical variables, chemotherapy was associated with a statistically significant decrease in the risk of death overall (hazard ratio, 0.78; 95% confidence interval, 0.69 to 0.88) and in patients with stage IB (HR, 0.58; 95% CI, 0.44-0.77) or stage II cancer (HR, 0.74; 95% CI, 0.60-0.90). The use of brachytherapy also was associated with significantly improved survival overall (HR, 0.67), in stage IA cancer (HR, 0.67), and in stage II cancer (HR, 0.64).
The survival effect of brachytherapy held up in additional subgroup analyses, Dr. Cham explained. In contrast, external beam radiation therapy was not associated with improved survival overall or in any subgroup, she said. The results highlight the potential use of vaginal brachytherapy in early-stage uterine papillary serous carcinoma, she emphasized.
Dr. Cham cited no funding sources and reported having no conflicts of interest.