BACKGROUND AND PURPOSE: Fractionation strategies delivered over 4 weeks are of clinical and radiobiological interest because treatment is completed before radiotherapy (RT) induced clonogen proliferation commences in earnest approximately 3 to 4 weeks into a course of RT. We wished to test the clinical hypothesis that an increased total dose delivered over 4 weeks with smaller than standard doses per fraction in locally advanced squamous cell carcinoma (SCC) may result in relative protection of late responding tissues and an increased tumor control compared to a conventional daily course in the same overall time. MATERIALS AND METHODS: Between 1988 and 1995 a randomized controlled trial employing RT alone was undertaken at the Princess Margaret Hospital that included 331 eligible patients with T3 or T4 N0 or any N-positive oropharynx, hypopharynx, or larynx primary SCC. RT was randomly assigned to one of two 4 week schedules, either 51 Gy in 20 equal daily fractions, termed conventional fractionation (CF), or 58 Gy in 40 equal fractions given twice per day as a hyperfractionated (HF) experimental arm. RESULTS: The 5-year local relapse rate was reduced in the HF (41%) compared to the CF arm (49%). This difference was marginally not significant (p=0.082) when the effect was not adjusted. When the effect of the treatment was adjusted by Cox model for clinical factors that included N-category, ECOG performance status, site of disease, T-category, age, hemoglobin, and gender the HF achieved a significant effect (p=0.02). Survival (40% vs. 30%) was also improved with HF compared to CF arm. This difference was only marginally not significant (p=0.069) but again achieved statistical significance when the model was adjusted for clinical factors (p=0.01). Similar results were observed for disease free survival. Although reversible acute toxicity was increased with HF, the overall 5-year rate of grade 3 and 4 late toxicity for the CF was 10.5% compared to 7.7% in the higher dose HF arm. CONCLUSIONS: HF delivered in 4 weeks permits enhanced RT doses achieving improved tumor control, without increased late toxicity, compared to daily fractionated radiotherapy in the same overall time.
RCT Entities:
BACKGROUND AND PURPOSE: Fractionation strategies delivered over 4 weeks are of clinical and radiobiological interest because treatment is completed before radiotherapy (RT) induced clonogen proliferation commences in earnest approximately 3 to 4 weeks into a course of RT. We wished to test the clinical hypothesis that an increased total dose delivered over 4 weeks with smaller than standard doses per fraction in locally advanced squamous cell carcinoma (SCC) may result in relative protection of late responding tissues and an increased tumor control compared to a conventional daily course in the same overall time. MATERIALS AND METHODS: Between 1988 and 1995 a randomized controlled trial employing RT alone was undertaken at the Princess Margaret Hospital that included 331 eligible patients with T3 or T4 N0 or any N-positive oropharynx, hypopharynx, or larynx primary SCC. RT was randomly assigned to one of two 4 week schedules, either 51 Gy in 20 equal daily fractions, termed conventional fractionation (CF), or 58 Gy in 40 equal fractions given twice per day as a hyperfractionated (HF) experimental arm. RESULTS: The 5-year local relapse rate was reduced in the HF (41%) compared to the CF arm (49%). This difference was marginally not significant (p=0.082) when the effect was not adjusted. When the effect of the treatment was adjusted by Cox model for clinical factors that included N-category, ECOG performance status, site of disease, T-category, age, hemoglobin, and gender the HF achieved a significant effect (p=0.02). Survival (40% vs. 30%) was also improved with HF compared to CF arm. This difference was only marginally not significant (p=0.069) but again achieved statistical significance when the model was adjusted for clinical factors (p=0.01). Similar results were observed for disease free survival. Although reversible acute toxicity was increased with HF, the overall 5-year rate of grade 3 and 4 late toxicity for the CF was 10.5% compared to 7.7% in the higher dose HF arm. CONCLUSIONS: HF delivered in 4 weeks permits enhanced RT doses achieving improved tumor control, without increased late toxicity, compared to daily fractionated radiotherapy in the same overall time.
Authors: G-One Ahn; Diane Tseng; Cho-Hwa Liao; Mary Jo Dorie; Agnieszka Czechowicz; J Martin Brown Journal: Proc Natl Acad Sci U S A Date: 2010-04-19 Impact factor: 11.205
Authors: Ambika Parmar; Michaelina Macluskey; Niall Mc Goldrick; David I Conway; Anne-Marie Glenny; Janet E Clarkson; Helen V Worthington; Kelvin Kw Chan Journal: Cochrane Database Syst Rev Date: 2021-12-20
Authors: Bertrand Baujat; Jean Bourhis; Pierre Blanchard; Jens Overgaard; Kian K Ang; Michelle Saunders; Aurélie Le Maître; Jacques Bernier; Jean Claude Horiot; Emilie Maillard; Thomas F Pajak; Michael G Poulsen; Abderrahmane Bourredjem; Brian O'Sullivan; Werner Dobrowsky; Hliniak Andrzej; Krzystof Skladowski; John H Hay; Luiz Hj Pinto; Karen K Fu; Carlo Fallai; Richard Sylvester; Jean Pierre Pignon Journal: Cochrane Database Syst Rev Date: 2010-12-08
Authors: Michelle Lenarduzzi; Angela B Y Hui; Nehad M Alajez; Wei Shi; Justin Williams; Shijun Yue; Brian O'Sullivan; Fei-Fei Liu Journal: PLoS One Date: 2013-01-15 Impact factor: 3.240