An abstract titled, “The Association between Use of Hypofractionated Radiation Therapy for the Treatment of Prostate Cancer and Treatment Completion” has been presented at the 2021 American Society for Radiation Oncology (ASTRO) Annual Meeting, which was held in Chicago, Illinois from October 24th through 27th. The study was conducted as a part of the ongoing outcomes research collaboration between HealthHelp and Humana.

While hypofractionated (HF) radiation therapy (RT) is recognized as a suitable treatment for low and intermediate risk prostate cancer, it is not yet the standard of care. As HF RT requires the patient to attend fewer appointments, it is potentially easier for patients to complete than conventional fractionation (CF) RT. Since noncompletion of RT has been shown to lead to inferior outcomes, use of HF RT may be a way to increase treatment adherence. To provide additional perspective on this question, this study examined whether there was a difference in RT treatment completion rates among patients with prostate cancer whom were given orders for HF RT versus CF RT.

Radiation therapy order data from a prior authorization program and health plan claims data were extracted. The data related to patients belonging to commercial and Medicare Advantage health plans from a national organization. The patients included had early stage prostate cancer, had not had prostatectomy, were not receiving palliative care, had no prior prostate cancer RT orders, and received their order for RT between July 1st, 2016 and September 30th, 2019. Orders were categorized as HF if they were authorized for 5 to 28 fractions of RT, and CF if they were authorized for 29 to 48 fractions. Each RT order was assigned a target date for completion, and completion was assessed on the basis of whether the patient had received the number of fractions authorized by that date. Patients with orders for five fractions were considered to have completed treatment if they received three or more fractions, as these were stereotactic body RT regimens that are adjusted based upon treatment response. A Chi-square test was used to evaluate the association between the authorized regimen and completion. A multivariate logistic regression was used to assess the same, after controlling for age, urbanicity, the median income of the patient’s home ZIP code, if the order was placed at a hospital, and if the ordering facility’s name suggested an academic affiliation. Finally, a multivariate logistic regression was used to assess whether any of the control variables were associated with the authorization of an HF regimen.

Of the 936 orders included, 309 (33.0%) were for HF and 627 (67.0%) were for CF. The completion rate significantly (P<.01) differed between the groups; 64.7% (200/309) for HF orders and 55.8% (350/627) for CF orders. Multivariate analysis found HF orders were significantly associated with treatment completion, relative to CF orders; 1.49 (95% CI: 1.12-1.99) adjusted odds. None of the other covariates were significantly associated with completion. Patients had significantly higher odds of having an order for HF if they came from a <$40,000 median income ZIP code (OR: 1.40; 95% CI: 1.01-1.93), or if the site of service at which the order was placed was a hospital (OR: 1.75; 95% CI: 1.26-2.42).

In response to the study’s findings, the study’s lead author, Adam C. Powell, Ph.D., remarked, “The HealthHelp / Humana research team has previously found in the context of breast cancer that patients receiving orders for hypofractionated radiation therapy were more likely to complete their treatments than patients receiving orders for conventional fractionation radiation therapy. This new finding in the context of prostate cancer is not surprising to us, as it is congruent with our prior finding. These findings suggest that in situations where hypofractionated radiation therapy is anticipated to provide equivalent outcomes to conventional fractionation radiation therapy, the potential for greater treatment adherence with a hypofractionated regimen should be considered during decision making.”

To learn more about ASTRO, visit https://www.astro.org/