Hypofractionated, Dose-Escalated Radiation Versus Conventionally Fractionated Radiation for Localized Prostate Cancer: Long-Term Update of a Phase III, Prospective, Randomized Controlled Trial

Author(s): Comron Hassanzadeh, MD, MPH1; Deborah Kuban, MD1; Sarah Pasyar, MS2; Roland Bassett, MS2; Patricia Troncoso, MD3; Maheen Ansari, BS1; Pamela Schlembach, MD1; Sean McGuire, MD, PhD1; Quynh Nguyen, MD1; Steven Frank, MD1; Henry Mok, MD1; Osama Mohamad, MD, PhD1; Ryan Park, MD1; Chad Tang, MD, PhD1; Weiliang Du, PhD4; Rajat Kudchadker, PhD4; Seungtaek Choi, MD1; Karen Hoffman, MD1;
Source: J Clin Oncol. 2025;43(18):2044-2048

Dr. Maen Hussein's Thoughts

In patients with localized prostate cancer, predominantly low-risk and intermediate-risk disease, the long-term update reveals 13-year outcomes. Treatment failure occurred less frequently in men undergoing HIMRT (n = 13) compared with those undergoing CIMRT.

ABSTRACT

The MD Anderson dose-escalated, hypofractionated prostate radiation study was a phase III randomized trial comparing conventionally fractionated intensity-modulated radiation therapy (CIMRT, 75.6 Gy in 1.8-Gy fractions) with dose-escalated, hypofractionated intensity-modulated radiation (HIMRT, 72 Gy in 2.4-Gy fractions) in patients with localized prostate cancer, predominantly low-risk and intermediate-risk disease. The initial publication highlighted statistically fewer treatment failures in the HIMRT arm. We present long-term updated 13-year outcomes to determine whether cancer control benefit was maintained and to evaluate distant metastases post hoc. With a median follow-up of 13.2 years (IQR, 8.8-15.9 years), treatment failure occurred less frequently in men undergoing HIMRT (n = 13) compared with those undergoing CIMRT (n = 22), although the difference no longer meets statistical significance (P = .08). Distant metastases were rare, and no statistically significant difference was noted (P = .2). There remained no statistically significant difference in late GI 2+ (10-year 10% HIMRT v 4% CIMRT, P = .09) or genitourinary grade 2+ toxicity (10-year 26% v 23%, P = .5).

Author Affiliations

1Department of Genitourinary Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX; 2Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX; 3Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX; 4Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX;

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