Journal Article

Proton versus photon radiotherapy in adults with primary brain tumors evaluating functional survival: a phase 3 randomized controlled trial study protocol (PRIDE)

Dasgupta, Archya, Kannan, Sadhana, Moiyadi, Aliasgar, Konthoujam, Manimala, Ranjith, C. P., Punde, Rohidas, Phurailatpam, Reena, Goswami, Savita, Chatterjee, Abhishek, Sridhar, Epari, Bano, Nazia, Ghosh, Suman, Menon, Nandini, Sutar, Avdhoot, Shinde, Prakash, Puranik, Ameya, Sahu, Arpita, Meena, Lilawati, Gupta, Tejpal, Patil, Divya

2026

Overview

Background Radiation therapy (RT) plays a significant role in the multimodal management of primary brain tumors, improving oncological outcomes. However, despite advances such as Intensity-Modulated Radiation Therapy (IMRT), photon-based RT inevitably exposes normal organs to low-dose radiation, leading to long-term functional morbidities like cognitive decline, endocrine dysfunction, auditory toxicity. These late effects are particularly concerning in patients with favorable prognoses and protracted survival. Proton beam therapy (PBT), owing to its unique physical properties, holds promise for better functional preservation, but robust clinical data in adults are lacking. Methods The PRIDE study is a prospective, open-label, phase 3 randomized controlled trial enrolling adults aged 18–70 years undergoing focal cranial RT with conventional fractionation for primary brain tumors with expected survival > 5 years at Tata Memorial Centre, Mumbai. Participants will be randomized 1:1 to receive either photon-IMRT (standard arm) or PBT (experimental arm), stratified by age, tumor type, proximity to the hypothalamic-pituitary axis, and radiation dose. The primary endpoint is 5-year functional survival, defined as survival without functional deterioration (neurocognitive decline, significant ototoxicity, new or worsening endocrine dysfunction, neurological impairment, severe radio-necrosis, disease progression, or death). Secondary endpoints include patient-reported quality of life and health economic analysis. Survival outcomes will be analyzed using Kaplan-Meier methods with log-rank test. Neurocognitive and quality-of-life data will be evaluated using linear mixed-effects and non-parametric tests. A total of 156 patients will be enrolled, accounting for 20% attrition, to detect a 25% absolute improvement in 5-year functional survival favoring PBT (65% vs 40%, HR 0.47, α=0.05, power=80%). An interim analysis has been planned using the O'Brien-Fleming rule after 50% of the events (n=28). Discussion This trial will provide level 1 evidence investigating the role of PBT in functional outcomes among adults with primary brain tumors. If study endpoint is achieved, PBT will be considered as standard of care guiding contemporary neuro-oncology practice. Registration The trial has been approved by the Institutional Ethics Committee of Tata Memorial Centre, Mumbai. The trial has been registered with the Clinical Trial Registry of India (CTRI/2025/03/082568) and Clinicaltrials.gov (study identifier NCT06831461).

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adolescent / Adult / Adults / Aged / Background radiation / Biomedical and Life Sciences / Biomedicine / Brain / Brain cancer / Brain Neoplasms - mortality / Brain Neoplasms - radiotherapy / Brain tumors / Brain tumours / Cancer / Cancer Research / Care and treatment / Clinical trials / Clinical Trials, Phase III as Topic / Cognition / Cognitive ability / Comparative analysis / Consent / Disease progression / Dosimetry / Economic analysis / Ethical standards / Female / Fractionation / Functional survival / Glioma / Humans / Hypothalamus / Imaging / Magnetic resonance imaging / Male / Medical diagnosis / Medical prognosis / Methods / Middle Aged / Necrosis / Neurocognition / Neurological complications / Oncology / Oncology, Experimental / Ototoxicity / Patients / Photons / Photons - therapeutic use / Physical properties / Physiological aspects / Pituitary / Planning / Prognosis / Prospective Studies / Proton beam therapy / Proton beams / Proton Therapy - methods / Proton Therapy - mortality / Quality of Life / Radiation / Radiation dosage / Radiation therapy / Radiology / Radiotherapy / Radiotherapy Dosage / Radiotherapy, Intensity-Modulated - methods / Randomized controlled trial / Randomized Controlled Trials as Topic / Rank tests / Study Protocol / Survival / Testing / Tumors / Young Adult