Health-related quality of life after single-fraction high-dose-rate brachytherapy and hypofractionated external beam radiotherapy for prostate cancer.
OBJECTIVE
To investigate the change in health-related quality of life for men after high-dose-rate brachytherapy and external beam radiotherapy for prostate cancer and the factors associated with this change.


METHODS
Eligible patients had clinically localized intermediate-risk prostate cancer. The patients received high-dose-rate brachytherapy as a single 15-Gy implant, followed by external beam radiotherapy to 37.5 Gy in 15 fractions. The patients were monitored prospectively for toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and health-related quality of life (Expanded Prostate Cancer Index Composite [EPIC]). The proportion of patients developing a clinically significant difference in the EPIC domain score (minimally important difference of >0.5 standard deviation) was determined and correlated with the baseline clinical and dosimetric factors. The study accrued 125 patients, with a median follow-up of 24 months.


RESULTS
By 24 months, 23% had Grade 2 urinary toxicity and only 5% had Grade 2 bowel toxicity, with no Grade 3 toxicity. The proportion of patients reporting a significant decrease in EPIC urinary, bowel, sexual, and hormonal domain scores was 53%, 51%, 45%, and 40% at 12 months and 57%, 65%, 51%, and 30% at 24 months, respectively. The proportion with a >1 standard deviation decrease in the EPIC urinary, bowel, sexual, and hormonal domain scores was 38%, 36%, 24%, and 20% at 12 months and 46%, 48%, 19%, and 8% at 24 months, respectively. On multivariate analysis, the dose to 10% of the urethra was associated with a decreasing EPIC urinary domain score (p = .0089) and, less strongly (p = .0312) with a decreasing hormonal domain score. No association was found between the prostate volume, bladder dose, or high-dose volume and urinary health-related quality of life. A high baseline International Index of Erectile Function score was associated (p = .0019) with a decreasing sexual domain score. The optimal maximal dose to 10% of the urethra cutpoint for urinary health-related quality of life was 120% of the prescription dose.


CONCLUSIONS
EPIC was a more sensitive tool for detecting the effects on function and bother than were the generic toxicity scales. The urethral dose had the strongest association with a deteriorating urinary quality of life.
Morton
Gerard C
GC
Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada. gerard.morton@sunnybrook.ca
Loblaw
D Andrew
DA
Chung
Hans
H
Tsang
Gail
G
Sankreacha
Raxa
R
Deabreu
Andrea
A
Zhang
Liying
L
Mamedov
Alexandre
A
Cheung
Patrick
P
Batchelar
Deidre
D
Danjoux
Cyril
C
Szumacher
Ewa
E
D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D002985:Clinical Protocols; D007172:Erectile Dysfunction / Q000209:etiology; D005500:Follow-Up Studies; D006471:Gastrointestinal Hemorrhage / Q000209:etiology; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011349:Proctitis / Q000209:etiology; D011446:Prospective Studies; D011467:Prostate / Q000473:pathology; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011788:Quality of Life; D012372:ROC Curve; D011878:Radiotherapy / Q000009:adverse effects; D011879:Radiotherapy Dosage; D012007:Rectum; D047368:Tumor Burden; D014521:Urethra / Q000528:radiation effects; D016055:Urinary Retention / Q000209:etiology