Racial Disparities in Brachytherapy Treatment among Women with Cervical and Endometrial Cancers: A United States Cohort Study between 2004 and 2017

Abstract

Brachytherapy (BT) improves clinical outcomes among women with cervical and endometrial cancers. Recent trends found decreasing BT rates in the United States; however, racial/ethnic differences have not been investigated completely. Here we aim to analyze 1) variations in BT practice patterns, 2) racial differences of BT, and 3) predictors of BT by race among women with cervical and endometrial cancers in the United States. A retrospective cohort of women with endometrial and cervical cancers in the US was evaluated using the National Cancer Database, between 2004 and 2017. Primary endpoint was treatment with BT. Women ≥18 years of age were included for FIGO Stage IA-IVA, non-surgically treated cervical cancers and high intermediate risk (PORTEC-2 and GOG-99 definition) or FIGO Stage II-IVA endometrial cancers. Racial groups were in accordance with federal guidelines including Asian, American Indian and Alaska Native (AIAN), Black, Native Hawaiian and other Pacific Islander (NHPI), and White. BT practice patterns and trends over time were evaluated by race. To identify predictors of BT by race, logistic regression calculated adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) after assessing for multicollinearity. A total of 13,857 women with cervical cancer and 140,942 women with endometrial cancer were included. Median follow-up was 69 months. Median (IQR) age was 53 (43-63) years for cervical cancer and 64 (57-72) years for endometrial cancer. Most cervical cancers were Stage III (44%), squamous cell carcinoma (88%), and lymphovascular space invasion (LVSI) positive (49%). Most endometrial cancers were Stage IB (45%), endometrioid histology (82%), and LVSI-positive (50%). Between 2004 and 2017, endometrial cancer BT increased (34% to 57%). BT rates for cervical cancer ranged from 65% NHPI, 63% Asian, 62% White, 59% AIAN, and 57% Black. BT rates for endometrial cancer ranged from 26% Black, 25% White, 25% Asian, 21% AIAN, and 20% NHPI. By race, only Black women with cervical cancer were significantly less likely to receive BT (aOR = 0.8; 95% CI = 0.7-0.9), compared to White women. Only NHPI women with endometrial cancer were less likely to receive BT (aOR = 0.7; 95% CI = 0.5-1.0), compared to White women. Community cancer center treatment was the only factor associated with a decreased odds of BT for both Black women with cervical cancer (aOR = 0.7; 95% CI = 0.6-0.9) and NHPI women with endometrial cancer (aOR = 0.3; 95% CI = 0.1-0.8), compared to academic centers. In this study of women diagnosed with endometrial and cervical cancers with stages known to benefit from BT, NHPI women with endometrial cancer and Black women with cervical cancer were less likely to receive brachytherapy compared to White women. Community engagement is needed to increase BT access for patients treated at community cancer centers to ensure equitable gynecologic cancer care.