July 25 (UPI) -- Research by the University of Pennsylvania suggests it is safe for women to use antiperspirants during radiotherapy for breast cancer.
The study, published in the July edition of Radiotherapy and Oncology, was conducted by researchers at the Perelman School of Medicine at the University of Pennsylvania.
The prevailing wisdom has been for doctors to advise their patients not to use antiperspirants during radiation therapy because it caused higher skin side effects -- eight of 10 patients reported their doctors told them not to use antiperspirant during treatment, despite research not backing up the concern.
"Antiperspirants have traditionally been proscribed during breast radiation for fear of increasing skin toxicity in the axillary region through a bolus effect or from electron scatter from aluminum which is the active ingredient in antiperspirants," Dr. Brian C. Baumann, lead author of the study, told UPI.
"Modern radiation therapy treatment is usually delivered with high-energy, mega-voltage x-ray beams which do not deliver significant doses of radiation to the skin surface, unlike lower energy x-ray beams which deliver more radiation to the skin surface and were used in the past. For mega-voltage radiation, the radiation needs a 'running start' as it enters the tissue before it reaches maximal dose. Any material added to the surface of the skin means that the maximum dose is deposited closer to the skin surface and a higher dose of radiation is delivered to the skin itself."
Researchers used the online cancer service Oncolink, created by Penn's Radiation Oncology unit, to create a survey to find out what percentage of providers still tell their patients not to use antiperspirants and what percentage of patients actually received the advice.
"Several randomized trials reported no significantly increased physician or patient-reported skin toxicity with non-aluminum deodorants or aluminum-containing antiperspirants," Baumann said. "Despite these studies, 82 percent of clinicians in our survey cling to traditional proscriptions against antiperspirants during radiation. A comparable number of patients [79 percent] reported that they had received this advice from their healthcare providers. The enduring popularity of this recommendation, even in the face of reports questioning the tradition's rationale, negatively impacts patients' quality-of-life."
Clinical trials have failed to show antiperspirant use leads to higher skin side effects during breast cancer radiation therapy.
For this study, researchers used optically stimulated luminescent dosimeters, or OSLDs, to measure the amount of surface radiation absorbed with each dose of radiation therapy. They used three squares of paper, a plain one, another with a thick coating of standard antiperspirant and a third with a thick coating of extra-strength antiperspirant, all placed within the radiation beam's path.
"We found no significant difference in surface dose with or without antiperspirant," Baumann said. "This study shows providers should be more liberal in letting patients use antiperspirants during radiation treatment, which may improve patient quality-of-life."