Phase II study of hypofractionated image-guided radiotherapy for localized prostate cancer: Outcomes of 55 Gy in 16 fractions at 3.4 Gy per fraction

• Published in: Radiotherapy and oncology Vol. 103; no. 2; pp. 210 - 216
• Main Authors: Wu, Jackson S.Y, Brasher, Penelope M.A, El-Gayed, Ali, Pervez, Nadeem, Tai, Patricia T, Robinson, John, Skarsgard, David, Joseph, Kurian, Sia, Michael A, Pearcey, Robert G
• Format: Journal Article
• Language: English
• Published: Ireland 01.05.2012
• Subjects: Aged; Aged, 80 and over; Dose Fractionation; Hematology, Oncology and Palliative Medicine; Humans; Male; Middle Aged; Prostatic Neoplasms - radiotherapy; Radiotherapy, Image-Guided; Treatment Outcome; Hypofractionation; Clinical trial; Patient-reported outcomes; Image-guided radiotherapy; Prostate cancer
• ISSN: 0167-8140; 1879-0887
• DOI: 10.1016/j.radonc.2011.12.020

Abstract Purpose To estimate the late morbidity of a novel, hypofractionated external beam radiotherapy schedule of 55 Gy in 16 fractions (4 fractions/week, 3.4 Gy per fraction) for localized prostate cancer. Methods and materials A multi-center phase 2 study enrolled seventy-three patients between September 2004 and June 2006. After insertion of fiducial gold markers, they were treated with image-guidance (IGRT) using conformal techniques with intensity-modulation, if necessary, and then followed every 6 months for toxicity rating and PSA. Patient reported outcomes were collected yearly. Median follow up was 4.6 years. Results At 4 years post-radiotherapy, the cumulative incidence of combined urinary and bowel grade 3 toxicity was 7% (95% CI 3–16%) and grade 2+ was 33% (95% CI 24–46%). All except two patients recovered from their grade 3 events. Patient-reported reduction of function was most pronounced at year two for urinary function (mean −7, SD 16), and at year one for bowel function (mean −7, SD 21). The cumulative incidence of biochemical (PSA nadir + 2) or biopsy-proven relapse at 4 years was 9% (95% CI 4–18%). Conclusions Hypofractionated radiotherapy is clinically feasible and more convenient than conventional schedules for patients with localized prostate cancer. Phase 3 multicenter studies are on-going ( NCT00126165 ).