Prostate Advanced Radiation Technologies Investigating Quality of Life (PARTIQoL): A Phase III Randomized Clinical Trial of Proton Therapy vs. IMRT for Low or Intermediate Risk Prostate Cancer.

Prostate cancer is the most common non-cutaneous cancer diagnosed among men in the United States, and the majority of patients are diagnosed with localized disease. Men with localized prostate cancer have several treatment options including external beam radiotherapy with either photons or protons. Proton beam therapy (PBT) has certain dosimetric advantages and the potential to reduce treatment-associated morbidity and improve oncologic outcomes, but current PBT is significantly more costly than intensity-modulated radiotherapy (IMRT). The PARTIQoL trial (NCT01617161) is the first multicenter phase 3 randomized trial comparing protons to photons in the treatment of localized prostate cancer.

Patients with low or intermediate risk prostate cancer (Stage T1c-T2c, PSA < 20, Gleason score ≤ 7) are randomized to receive either PBT or IMRT, with targeted recruitment efforts for minority populations. A companion registry study has concurrently enrolled patients who declined randomization or whose insurance denied coverage for PBT. Patients are stratified by clinical site, age, use of rectal spacer, and fractionation schedule (conventional fractionation: 79.2 Gy in 44 fractions vs moderate hypofractionation: 70.0 Gy in 28 fractions). Participants are followed longitudinally to assess patient-reported outcomes (PROs) of bowel, urinary, and erectile function for 60 months after completion of radiotherapy (with an option for additional follow up through 10 years). Participants may also participate in correlative studies, including serial CT imaging during treatment and analyses of biopsy tissue, blood and urine specimens. The primary objective is to compare PROs of bowel function using the EPIC score at 24 months following completion of radiation. Secondary objectives are to assess treatment-related differences in urinary and erectile functions, adverse events, efficacy endpoints (biochemical control, metastasis-free survival, disease-specific survival, and overall survival), health state utilities, perceptions of care, late effects, cost-effectiveness, association between radiotherapy dose distribution and PROs, and to identify biomarkers of radiation response and toxicity.

The randomized trial has completed accrual, with 450 patients enrolled at 27 sites between June 2012 and November 2021. 20.3% of patients enrolled are non-white. Accrual on the companion registry is active, with 354 patients enrolled as of February 2023.

Follow-up for the primary endpoint on the randomized trial will be reached in 2024. The PARTIQoL randomized clinical trial will rigorously assess the clinical benefits of PBT relative to IMRT and results will inform decision making by patients, providers, policymakers, and payers.

International journal of radiation oncology, biology, physics. 2023 Oct 01 [Epub]

A J Wisdom, B Y Yeap, J M Michalski, A L Zietman, B C Baumann, J P Christodouleas, S C Kamran, R R Parikh, N Vapiwala, R J Ellis, W F Hartsell, D T Miyamoto, J Zeng, T M Pisansky, M V Mishra, D E Spratt, N P Mendenhall, E M Soffen, J E Bekelman, J A Efstathiou

Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA., Department of Medicine, Division of Hematology & Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA., Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO., Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA., Washington University School of Medicine in St. Louis, Department of Radiation Oncology, St. Louis, MO., Department of Radiation Oncology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA., Massachusetts General Hospital, Boston, MA., Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ., Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA., GenesisCare USA, Cape Coral, FL., Department of Radiation Oncology, Northwestern Medicine Proton Center, Warrenville, IL., Department of Radiation Oncology, University of Washington - Fred Hutchinson Cancer Center, Seattle, WA., Department of Radiation Oncology, Mayo Clinic, Rochester, MN., University of Maryland School of Medicine, Baltimore, MD., Department of Radiation Oncology, University Hospitals Seidman Cancer Center and Case Western Reserve University, Cleveland, OH., Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL., Princeton Radiation Oncology, Jamesburg, NJ.