Ong, ALK, Knight, K, Panettieri, V, Dimmock, MR, Tuan, JKL, Tan, HQ and Wright, C (2022) Dose-volume analysis of planned versus accumulated dose as a predictor for late gastrointestinal toxicity in men receiving radiotherapy for high-risk prostate cancer. Physics and Imaging in Radiation Oncology, 23. 97 - 102. ISSN 2405-6316

[thumbnail of dose_volume_analysis.pdf]
dose_volume_analysis.pdf - Published Version
Available under License Creative Commons Attribution.

Download (840kB) | Preview


Background and purpose: Significant dose deviations have been reported between planned (DP) and accumulated (DA) dose in prostate radiotherapy. This study aimed to develop multivariate analysis (MVA) models associating Grade 1 and 2 gastrointestinal (GI) toxicity with clinical and DP or DA dosimetric variables separately. Materials and methods: Dose volume (DV) metrics were compared between DA and DP for 150 high-risk prostate cancer patients. MV models were generated from significant clinical and dosimetric variables (p < 0.05) at univariate level. Dose-based-region of interest (DB-ROI) metrics were included. Model performance was measured, and additional subgroup analysis were performed. Results: Rectal DA demonstrated a higher intermediate-high dose (V30-65 Gy and DB-ROI at 15-50 mm) compared to DP. Conversely, at the very high dose region, rectal DA (V75 Gy and DB-ROI at 5-10 mm) were significantly lower. In MVA, rectal DB-ROI at 10 mm was predictive for Grade ≥ 1 GI toxicity for DA and DP. Age, rectal DA for D0.03 cc, and rectal DP for DB-ROI 10 mm were predictors for Grade 2 GI toxicity. Subgroup analysis revealed that patients ≥ 72 years old and a rectal DA of ≥ 78.2 Gy were highly predictive of Grade 2 GI toxicity. Conclusions: The dosimetric impact of a higher dose rectal dose in DA due to volumetric changes was minimal and was not predictive of detrimental clinical toxicity apart from rectal D0.03 cc ≥ 78.2 Gy for Grade 2 GI toxicity. The use of the DB-ROI method can provide equivalent predictive power as the DV method in toxicity prediction.

Item Type: Article
Uncontrolled Keywords: Accumulated dose; Predictive model; Gastrointestinal toxicity; High-risk prostate; Volumetric image-guidance
Subjects: R Medicine > R Medicine (General)
R Medicine > RM Therapeutics. Pharmacology
Divisions: Faculty of Medicine and Health Sciences > School of Allied Health Professions
Related URLs:
Depositing User: Symplectic
Date Deposited: 09 Aug 2022 09:45
Last Modified: 09 Aug 2022 09:45

Actions (login required)

View Item
View Item