Racial Disparities in Radiotherapy Regimens for Prostate and Breast Cancer

Cancer treatment in a modern medical private clinic or hospital with a linear accelerator. Professional doctors team working while the woman is undergoing radiation therapy for cancer
Black cancer patients are less likely than their White counterparts to receive shorter radiotherapy regimens, a study suggests.

A new study suggests that Black cancer patients are less likely than their White counterparts to receive shorter radiotherapy (RT) regimens, despite evidence showing that shorter RT regimens are associated with higher rates of treatment completion.

The study showed that Black patients with prostate cancer were less likely than their White counterparts to receive stereotactic body radiotherapy (SBRT) or moderately hypofractionated external-beam radiotherapy (mEBRT).

In addition, Black patients with breast cancer were less likely than their White counterparts to receive hypofractionated EBRT. These findings were published in JCO Oncology Practice.

For this study, researchers evaluated data from the National Cancer Database. The cohort included 170,386 men with localized prostate cancer who underwent definitive RT without radical prostatectomy and 306,846 women with nonmetastatic breast cancer who underwent RT after mastectomy or lumpectomy. 

In the breast cancer cohort, 12.3% of patients were Black. In the prostate cancer cohort, 17.5% of patients were Black. 

Prostate Cancer Cohort

In a multivariate analysis, race and treatment technique were independently associated with noncompletion of RT in the prostate cancer cohort. 

Black patients had a higher rate of treatment noncompletion than White patients — 13.4% and 12.2%, respectively (odds ratio [OR], 1.07; 95% CI, 1.03-1.12; P <.001).

When compared with conventional EBRT (cEBRT), the odds of treatment noncompletion were lower with mEBRT and SBRT. The rate of treatment noncompletion was 7.4% in mEBRT recipients and 13.2% in cEBRT recipients (OR, 0.81; 95% CI, 0.72-0.92; P =.001). The rate of noncompletion was 1.3% in the SBRT recipients (OR vs cEBRT, 0.08; 95% CI, 0.07-0.10; P <.001). 

Among patients who received cEBRT, Black patients had a higher rate of treatment noncompletion than White patients — 14.1% and 13.0%, respectively (OR, 1.07; 95% CI, 1.03-1.12; P <.001). However, there was no significant difference by race when it came to noncompletion of SBRT or mEBRT.

Overall, Black patients were less likely to receive SBRT or mEBRT than White patients — 7.4% and 8.3%, respectively (OR, 0.83; 95% CI, 0.78-0.88; P <.001). 

Breast Cancer Cohort

In a multivariate analysis, there was no significant difference in treatment noncompletion by race in the breast cancer cohort. The rate of noncompletion was 2.8% among Black patients and 2.0% among White patients (OR, 1.01; 95% CI, 0.93-1.08; P = .89).

However, hEBRT was associated with lower odds of treatment noncompletion than cEBRT. The rate of noncompletion was 1.0% and 2.3%, respectively (OR, 0.39; 95% CI, 0.35-0.44; P <.001). 

hEBRT was associated with lower odds of noncompletion regardless of race. Among Black patients, the rate of noncompletion was 1.7% for hEBRT and 2.9% for cEBRT (OR, 0.58; 95% CI, 0.44-0.75; P <.001). Among White patients, the rates were 0.9% and 2.2%, respectively (OR, 0.37; 95% CI, 0.33-0.42; P <.001).

There was no significant difference by race when it came to noncompletion of hEBRT or cEBRT.

Overall, Black patients were less likely to receive hEBRT than White patients — 10.4% and 15.3%, respectively (OR, 0.78; 95% CI, 0.75-0.81; P <.001).

“Black patients were consistently less likely to receive hypofractionated radiation for PC [prostate cancer] or BC [breast cancer], despite evidence suggesting that shorter regimens may lower rates of treatment noncompletion with similar oncologic outcomes,” the researchers concluded.

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

Reference

Dee EC, Taunk NK, Chino FL, et al. Shorter radiation regimens and treatment noncompletion among patients with breast and prostate cancer in the United States:An analysis of racial disparities in access and quality. JCO Oncol Pract. Published online November 18, 2022. doi:10.1200/OP.22.00383

This article originally appeared on Cancer Therapy Advisor