scholarly journals Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer

2018 ◽  
Vol 36 (29) ◽  
pp. 2943-2949 ◽  
Author(s):  
Karen E. Hoffman ◽  
K. Ranh Voong ◽  
Lawrence B. Levy ◽  
Pamela K. Allen ◽  
Seungtaek Choi ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Randomized Trial ◽  
Intensity Modulated Radiation Therapy ◽  
Cancer Control ◽  
Localized Prostate Cancer ◽  
Intensity Modulated ◽  
Genitourinary Toxicity ◽  
Gi Toxicity ◽  
Conventionally Fractionated

Purpose Hypofractionated radiotherapy delivers larger daily doses of radiation and may increase the biologically effective dose delivered to the prostate. We conducted a randomized trial testing the hypothesis that dose-escalated, moderately hypofractionated intensity-modulated radiation therapy (HIMRT) improves prostate cancer control compared with conventionally fractionated IMRT (CIMRT) for men with localized prostate cancer. Patients and Methods Men were randomly assigned to 75.6 Gy in 1.8-Gy fractions delivered over 8.4 weeks (CIMRT) or 72 Gy in 2.4 Gy fractions delivered over 6 weeks (HIMRT, biologically equivalent to 85 Gy in 1.8-Gy fractions assuming prostate cancer α-to-β ratio of 1.5). Failure was defined as prostate-specific antigen (PSA) failure (nadir plus 2 ng/mL) or initiation of salvage therapy. Modified Radiation Therapy Oncology Group criteria were used to grade late (≥ 90 days after completion of radiotherapy) GI and genitourinary toxicity. Results Most of the 206 men (72%) had cT1, Gleason score 6 or 7 (99%), and PSA level ≤ 10 ng/mL (90%) disease. Androgen deprivation therapy was received by 24%. With a median follow-up of 8.5 years, men treated with HIMRT experienced fewer treatment failures (n = 10) than men treated with CIMRT (n = 21; P = .036). The 8-year failure rate was 10.7% (95% CI, 5.8% to 19.1%) with HIMRT and 15.4% (95% CI, 9.1% to 25.4%) with CIMRT. There was no difference in overall survival ( P = .39). There was a nonsignificant increase in late grade 2 or 3 GI toxicity with HIMRT (8-year 5.0% v 12.6%; P = .08). However, GI toxicity was only 8.6% when rectal volume receiving 65 Gy of HIMRT was ≤ 15%. Late genitourinary toxicity was similar ( P = .84). There was no grade 4 toxicity. Conclusion The results of this randomized trial demonstrate superior cancer control for men with localized prostate cancer who receive dose-escalated moderately hypofractionation radiotherapy while shortening treatment duration.

Pilot study of moderately-hypofractionated intensity-modulated radiation therapy over 3 weeks for localized prostate cancer.

2018 ◽  
Vol 36 (6_suppl) ◽  
pp. 8-8
Author(s):  
Kiyonao Nakamura ◽  
Haruo Inokuchi ◽  
Itaru Ikeda ◽  
Tomomi Kamba ◽  
Takahiro Inoue ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Pilot Study ◽  
Intensity Modulated Radiation Therapy ◽  
Incidence Rates ◽  
Localized Prostate Cancer ◽  
Intermediate Risk ◽  
Biochemical Relapse ◽  
Intensity Modulated ◽  
Conventionally Fractionated

8 Background: The purpose of this trial was to prospectively evaluate the short-term outcomes of moderately hypofractionated intensity-modulated radiation therapy (MH-IMRT) for localized prostate cancer. Methods: In November 2013, we started a pilot study of MH-IMRT for prostate cancer. Eligible patients were 50 to 80 years old and had D’Amico’s low- or intermediate-risk disease. Fifty-four Gy in 15 fractions (3.6 Gy per fraction), in which the equivalent total dose in 2-Gy fractions to prostate cancer was estimated about 78 Gy, were delivered over 3 weeks using image-guided IMRT based on daily cone beam CT without intraprostatic fiducial markers. Neoadjuvant androgen deprivation therapy was given 4 to 8 months before the start of IMRT. The primary endpoint was incidence rates of acute toxicities, and the secondary endpoints were incidence rates of late toxicities at 2 years and biochemical relapse free survival (BRFS) at 2 years. Acute toxicities were evaluated based on the Common Terminology Criteria for Adverse Events version 4.0 criteria. Late toxicities were evaluated based on RTOG/EORTC Late Radiation Morbidity Scoring Schema. Biochemical relapse was defined according to the Phoenix definition (absolute nadir + 2 ng/ml). The planned sample size was 25 patients. Results: Twenty-five patients were enrolled in this trial. Twenty-four patients were treated with MH-IMRT, and 1 patient was treated with conventionally fractionated IMRT because his small intestine was close to the target. The median age in the cohort was 71 years old, and median follow-up period was 31 months (range 24-42). Four patients (17%) had low- and 20 (83%) had intermediate-risk disease. No grade ≥3 acute toxicity was observed and the incidence rates of grade 2 acute genitourinary and gastrointestinal toxicities were 21% and 4%, respectively. So far no grade ≥2 late toxicity has been observed and the 2-year BRFS is 95.8%. Transient PSA elevation over 0.4 ng/ml was observed in 11 patients (46%) and in 5 patients (21%) PSA rose ≥1.0 ng/ml above nadir. Conclusions: Sort-term outcome of MH-IMRT delivering 54 Gy in 15 fractions over 3 weeks for prostate cancer was comparable to that of conventionally fractionated IMRT. Clinical trial information: UMIN000012057.

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