Moderately Hypofractionated Intensity Modulated Radiation Therapy With Simultaneous Integrated Boost for Prostate Cancer: Five-Year Toxicity Results From a Prospective Phase I/II Trial

• Published in: Frontiers in oncology Vol. 10; p. 1686
• Main Authors: Ricco, Anthony, Mukhopadhyay, Nitai, Deng, Xiaoyan, Holdford, Diane, Skinner, Vicki, Saraiya, Siddharth, Moghanaki, Drew, Anscher, Mitchell S, Chang, Michael G
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 21-08-2020
• Subjects: clinical trial; moderate hypofractionation; Oncology; patient reported outcome measures; pelvic lymph nodes; prostate radiation therapy; simultaneous integrated boost; clinical trial; moderate hypofractionation; simultaneous integrated boost; genitourinary toxicity; patient reported outcome measures; gastrointestinal toxicity; pelvic lymph nodes; prostate radiation therapy
• ISSN: 2234-943X; 2234-943X
• DOI: 10.3389/fonc.2020.01686

In this phase I/II trial, 5-year physician-assessed toxicity and patient reported quality of life data is reported for patients undergoing moderately hypofractionated intensity modulated radiation therapy (IMRT) for prostate cancer using a simultaneous integrated boost (SIB) and pelvic lymph node (LN) coverage.
Patients with T1-T2 localized prostate cancer were prospectively enrolled, receiving risk group based coverage of prostate ± seminal vesicles (SVs) ± pelvic lymph nodes (LNs). Low risk (LR) received 69.6 Gy/29 fractions to the prostate, while intermediate risk (IR) and high risk (HR) patients received 72 Gy/30fx to the prostate and 54Gy/30fx to the SVs. If predicted risk of LN involvement >15%, 50.4 Gy/30fx was delivered to pelvic LNs. Androgen deprivation therapy was given to IR and HR patients.
There were 55 patients enrolled and 49 patients evaluable at a median follow up of 60 months. Included were 11 (20%) LR, 23 (41.8%) IR, and 21 (38.2%) HR patients. Pelvic LN treatment was given in 25 patients (51%). Prevalence rates of late grade 2 GI toxicity at 1, 3, and 5 years was 5.8, 3.9, and 5.8%, respectively, with no permanent grade 3 events. Prevalence rates of late grade 2 GU toxicity at 1, 3, and 5 years rates were 15.4, 7.7, and 13.5%, respectively, with three grade 3 events (5.8%). The biochemical relapse free survival at 5 years was 88.3%. There were no local, regional, or distant failures, with all patients still alive at last follow up.
Moderate hypofractionation of localized prostate cancer utilizing a SIB technique and LN coverage produces tolerable acute/late toxicity. Given equivalent efficacy between moderate hypofractionation schedules, the optimal regimen will be determined by long-term toxicity reported from both the physician and patient perspective.
www.ClinicalTrials.gov, identifier NCT01117935, Date of Registration: 5/6/2010.