Black children with cancer may be less likely to undergo proton radiotherapy, according to a study. The analysis observed a correlation between race and proton radiotherapy treatment, while neighborhood poverty level did not appear to be a significant factor.
“Proton radiotherapy is a high-cost, limited resource, for which the most robust evidence-based indications are in pediatric cancers owing to its ability to reduce long-term adverse effects compared with photon therapy,” the study authors stated. Barriers exist to receiving proton radiotherapy, they noted. The treatment is often performed in metropolitan areas or at major academic centers, so a physician referral is usually needed. Proton radiotherapy is performed daily for eight weeks, so depending on a patient’s residence, they may have to relocate for the duration of treatment.
“Owing to the potential barriers to proton radiotherapy access, we aimed to assess the association of race and socioeconomic factors with proton use in patients with solid malignant diseases enrolled on Children’s Oncology Group (COG) prospective trials,” the researchers wrote.
Patients who underwent external beam radiotherapy on COG solid tumor prospective trials in which the physician chose between proton or photon radiotherapy were included. Exclusion criteria included enrollment in a trial that only allowed emergency palliative radiotherapy or total body irradiation, not from the U.S., or having missing radiotherapy modality data. Patients were stratified by race: white non-Hispanic, white Hispanic, black, other, and unknown.
Final analysis included 1,240 patients; most patients (n=1,054; 85%) underwent photon radiotherapy, with just 15% (n=186) receiving proton radiotherapy. Black patients were less likely than white patients to receive proton radiotherapy (odds ratio [OR]=0.4; 95% confidence interval [CI], 0.22 to 0.75; P=0.004). Factors associated with decreased likelihood of receiving proton radiotherapy included enrollment in non-CNS trials (vs. CNS trials), shorter distance between enrolling and radiotherapy institution, and metastatic disease. No significant correlations were observed between insurance type, neighborhood poverty level, or gender and radiation modality. Outcomes were similar between univariate and multivariate analyses, except that in the latter, CNS trial enrollment was no longer a significant factor. When adjusting for enrolling institution location, distance to radiotherapy facility, and metastatic disease, black patients were still less likely than white patients to receive proton radiotherapy (OR=0.35; 95% CI, 0.17 to 0.72; P=0.004).
The analysis was published in JAMA Oncology.
“The reported racial disparities are concerning, particularly as this cohort represents a selected population of patients treated in prospective national clinical trials. Our results suggest that a racial disparity in proton radiotherapy use may exist; additional confirmatory investigation is needed,” concluded the study authors.