The Vienna Rectoscopy Score (VRS; from 0, absence of rectal mucosal changes, to 5) assessed 1 year after radiotherapy is a surrogate end-point of late rectal toxicity. The aim of this study was to investigate the association between treatment-related factors and 1-year VRS.
We performed a retrospective analysis of prospectively collected data. Patients with prostate adenocarcinoma treated with definitive or postoperative radiotherapy (RT) underwent endoscopy 1 year after RT. Relationships between VRS of 2 or more and treatment parameters were investigated by univariate and multivariate logistic analyses.
One hundred and ninety-five patients (mean age=69 years; range=43-81 years) were considered eligible for the study. At univariate analysis, patients treated with hypofractionation plus radiosurgery boost (p<0.001) and an equivalent dose in 2 Gy per fraction (EQD2) (α/β=3) ≥75 Gy (p<0.001) was associated with a significantly higher incidence of VRS ≥2 after 1 year of follow-up. At multivariate analysis, radiosurgery boost was an independent risk factor for developing rectal mucosal lesions (VRS ≥2), yielding an odds ratio (OR) of 4.14 (95% confidence interval (CI)=1.2-13.8), while pelvic surgery was inversely associated with VRS ≥2 (OR=0.39; 95% CI=0.17-0.94).
Hypofractionation followed by radiosurgery boost significantly increased the risk of developing late-onset rectal mucosal changes. Therefore, special care and preventative treatment strategies are needed when using radiosurgery boost after hypofractionated RT.
In vivo (Athens, Greece). 0000 Jan [Epub]
Edy Ippolito, Alessandra Guido, Gabriella Macchia, Francesco Deodato, Lucia Giaccherini, Andrea Farioli, Alessandra Arcelli, Dajana Cuicchi, Leonardo Frazzoni, Savino Cilla, Milly Buwenge, Giovanna Mantini, Anna R Alitto, Marianna Nuzzo, Vincenzo Valentini, Marcello Ingrosso, Alessio G Morganti, Lorenzo Fuccio
Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy., Radiation Oncology Center, Department of Experimental, Diagnostic and Specialty Medicine DIMES, University of Bologna, Bologna, Italy ., Radiotherapy Unit, Giovanni Paolo II Research and Care Foundation, Campobasso, Italy., Radiation Oncology Center, Department of Experimental, Diagnostic and Specialty Medicine DIMES, University of Bologna, Bologna, Italy., Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy., Medical Physics Unit, Giovanni Paolo II Research and Care Foundation, Campobasso, Italy., Department of Radiotherapy, A. Gemelli Hospital, Sacred Heart Catholic University, Rome, Italy., Endoscopy Unit, Giovanni Paolo II Research and Care Foundation, Campobasso, Italy.