- 1College of Nursing, Michigan State University, East Lansing, Michigan, USA. Electronic address: gwen.wyatt@hc.msu.edu.
- 2Department of Statistics and Probability, Michigan State University, East Lansing, Michigan, USA.
- 3Department of Statistics, Columbia University, New York, New York, USA.
- 4School of Medicine, Southern Illinois University, Springfield, Illinois, USA.
- 5Sparrow Radiation Oncology, Sparrow Health System, Lansing, Michigan, USA.
Abstract
CONTEXT:
Lower urinary tract symptoms (LUTSs) affect 75%-80% of men undergoing radiation therapy (RT) for prostate cancer.
OBJECTIVES:
To
determine the safety, maximum tolerated dose (MTD), and preliminary
efficacy of Serenoa repens commonly known as saw palmetto (SP) for
management of LUTS during RT for prostate cancer.
METHODS:
The
dose finding phase used the time-to-event continual reassessment method
to evaluate safety of three doses (320, 640, and 960 mg) of SP.
Dose-limiting toxicities were assessed for 22 weeks using the Common
Terminology Criteria for Adverse Events for nausea, gastritis, and
anorexia. The exploratory randomized controlled trial phase assessed
preliminary efficacy of the MTD against placebo. The primary outcome of
LUTS was measured over 22 weeks using the International Prostate Symptom
Score. Additional longitudinal assessments included quality of life
measured with the Functional Assessment of Cancer Therapy-Prostate.
RESULTS:
The
dose finding phase was completed by 27 men who reported no
dose-limiting toxicities and with 20 participants at the MTD of 960 mg
daily. The exploratory randomized controlled trial phase included 21
men, and no statistically significant differences in the International
Prostate Symptom Score were observed. The prostate-specific concerns
score of the Functional Assessment of Cancer Therapy-Prostate improved
in the SP group (P = 0.03). Of 11 men in the placebo group, two received
physician-prescribed medications to manage LUTS compared with none of
the 10 men in the SP group.
CONCLUSION:
SP at 960 mg may be a safe herbal supplement, but its efficacy in managing LUTS during RT needs further investigation.
Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
KEYWORDS:
Herbal supplement; lower urinary tract symptoms; prostate cancer; saw palmetto