Plan quality and dosimetric association of patient-reported rectal and urinary toxicities for prostate stereotactic body radiotherapy. Issue 1 (October 2016)

• Record Type: Journal Article
• Authors: Qi, X. Sharon; Wang, Jason P.; Gomez, Caitlin L.; Shao, Weber; Xu, Xiaoqing; King, Christopher; Low, Daniel A.; Steinberg, Michael; Kupelian, Patrick
• Is Part Of: Radiotherapy and oncology. Volume 121:Issue 1(2016:Oct.)
• Page Start: 113
• Page End: 117
• Publication Date: 2016-10
• Subjects: Prostate cancer -- Stereotactic body radiotherapy (SBRT) -- Plans quality -- Quality-of-life (QOL) -- Minimally clinically important difference (MID); Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2016.08.012
• Languages: English
• ISSNs: 0167-8140

Abstract

Abstract: Background and purpose: To study the association between dosimetric parameters with patient-reported quality-of-life (QOL) in urinary irritative/incontinency and bowel functions for prostate stereotactic body radiotherapy (SBRT). Material and methods: The patient-reported QOL was evaluated using the Expanded Prostate Cancer Index Composite (EPIC-26). According to the progression in QOL score over 12 months, patients were assigned to one of three subgroups: score decrement, no change, or increment. The dosimetric parameters were cross-compared among subgroups in urinary and bowel domains using univariate Analysis of Variance (ANOVA). The evaluated dosimetric metrics included target volume, V100 (volume receiving 100% prescription dose); rectal volume/dose–volume endpoints, maximum/mean doses; bladder volume/dose–volume endpoints, and maximum/mean doses. Results: Patients with consistent QOL reduction in urinary irritation function were significantly associated with greater mean bladder dose, greater V85/V90/V95/V100 and D 2cc / D 10cc . Patients with QOL reduction in urinary incontinence were marginally associated with greater mean bladder dose ( p = 0.06). None of the evaluated dosimetric parameters showed a significant correlation with QOL score change in bowel function. Conclusions: Patients with large prostate size were more susceptible to QOL decrements for urinary irritative and incontinency functions. Large bladder V85/V90/V95/V100 was associated with QOL decrements in the urinary irritative domain at 1-year after prostate SBRT.