Dataset Information

Inter-institutional analysis demonstrates the importance of lower than previously anticipated dose regions to prevent late rectal bleeding following prostate radiotherapy.

ABSTRACT: PURPOSE:To investigate whether inter-institutional cohort analysis uncovers more reliable dose-response relationships exemplified for late rectal bleeding (LRB) following prostate radiotherapy. MATERIAL AND METHODS:Data from five institutions were used. Rectal dose-volume histograms (DVHs) for 989 patients treated with 3DCRT or IMRT to 70-86.4?Gy@1.8-2.0?Gy/fraction were obtained, and corrected for fractionation effects (?/??=?3?Gy). Cohorts with best-fit Lyman-Kutcher-Burman volume-effect parameter a were pooled after calibration adjustments of the available LRB definitions. In the pooled cohort, dose-response modeling (incorporating rectal dose and geometry, and patient characteristics) was conducted on a training cohort (70%) followed by final testing on the remaining 30%. Multivariate logistic regression was performed to build models with bootstrap stability. RESULTS:Two cohorts with low bleeding rates (2%) were judged to be inconsistent with the remaining data, and were excluded. In the remaining pooled cohorts (n?=?690; LRB rate?=?12%), an optimal model was generated for 3DCRT using the minimum rectal dose and the absolute rectal volume receiving less than 55?Gy (AUC?=?0.67; p?=?0.0002; Hosmer-Lemeshow p-value, pHL?=?0.59). The model performed nearly as well in the hold-out testing data (AUC?=?0.71; p?

SUBMITTER: Thor M

PROVIDER: S-EPMC6628908 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Inter-institutional analysis demonstrates the importance of lower than previously anticipated dose regions to prevent late rectal bleeding following prostate radiotherapy.

Thor Maria M Jackson Andrew A Zelefsky Michael J MJ Steineck Gunnar G Karlsdòttir Asa A Høyer Morten M Liu Mitchell M Nasser Nicola J NJ Petersen Stine E SE Moiseenko Vitali V Deasy Joseph O JO

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 20180309 1

<h4>Purpose</h4>To investigate whether inter-institutional cohort analysis uncovers more reliable dose-response relationships exemplified for late rectal bleeding (LRB) following prostate radiotherapy.<h4>Material and methods</h4>Data from five institutions were used. Rectal dose-volume histograms (DVHs) for 989 patients treated with 3DCRT or IMRT to 70-86.4 Gy@1.8-2.0 Gy/fraction were obtained, and corrected for fractionation effects (α/β = 3 Gy). Cohorts with best-fit Lyman-Kutcher-Burman volu ...[more]

PMID: 29530433

Similar Datasets

Project description:An 87-year-old-man with prostate-cancer-stage-T1c-Gleason-6 treated with radiotherapy in 1996, recurrent prostate cancer treated with leuprolide hormonal therapy in 2009, and bladder-urothelial-carcinoma in situ treated with Bacillus-Calmette-Guerin and adriamycin in 2010, presented in 2015 with painless, bright red blood per rectum coating stools daily for 5 mo. Rectal examination revealed bright red blood per rectum; and a hard, fixed, 2.5 cm × 2.5 cm mass at the normal prostate location. The hemoglobin was 7.6 g/dL (iron saturation = 8.4%, indicating iron-deficiency-anemia). Abdominopelvic-CT-angiography revealed focal wall thickening at the bladder neck; a mass containing an air cavity replacing the normal prostate; and adjacent rectal invasion. Colonoscopy demonstrated an ulcerated, oozing, multinodular, friable, 2.5 cm × 2.5 cm mass in anterior rectal wall, at the usual prostate location. Histologic and immunohistochemical analysis of colonoscopic biopsies of the mass revealed poorly-differentiated-carcinoma of urothelial origin. At visceral angiography, the right-superior-rectal-artery was embolized to achieve hemostasis. The patient subsequently developed multiple new metastases and expired 13 mo post-embolization. Comprehensive literature review revealed 16 previously reported cases of rectal involvement from bladder urothelial carcinoma, including 11 cases from direct extension and 5 cases from metastases. Patient age averaged 63.7 ± 9.6 years (all patients male). Rectal involvement was diagnosed on average 13.5 ± 11.8 mo after initial diagnosis of bladder urothelial carcinoma. Symptoms included constipation/gastrointestinal obstruction-6, weight loss-5, diarrhea-3, anorexia-3, pencil thin stools-3, tenesmus-2, anorectal pain-2, and other-5. Rectal examination in 9 patients revealed annular rectal constriction-6, and rectal mass-3. The current patient had the novel presentation of daily bright red blood per rectum coating the stools simulating hemorrhoidal bleeding; the novel mechanism of direct bladder urothelial carcinoma extension into rectal mucosa via the prostate; and the novel aforementioned colonoscopic findings underlying the clinical presentation.

Dataset Information

Inter-institutional analysis demonstrates the importance of lower than previously anticipated dose regions to prevent late rectal bleeding following prostate radiotherapy.

Publications

Inter-institutional analysis demonstrates the importance of lower than previously anticipated dose regions to prevent late rectal bleeding following prostate radiotherapy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets