A new study has found that high doses of a common hormonal treatment used for excessive hair growth, early puberty, and prostate cancer, are linked to an increased risk of meningioma, a common type of benign brain tumor, according to Science Daily.
A meningioma is a tumor that forms on membranes that cover the brain and spinal cord just inside the skull, according to WebMD. These tumors are often slow-growing. Nearly 90% are benign (not cancerous).
The study has shown an association between the growth of meningioma and hormonal treatments, particularly prolonged and high dose use of cyproterone acetate (CPA).
CPA is an antiandrogen and progestin medication used in the treatment of androgen-dependent conditions such as acne, excessive hair growth, early puberty, and prostate cancer. It is a component of feminizing hormone therapy for transgender women and in birth control pills.
CPA is also made in combination with the female hormone estrogen to treat androgen-associated alopecia or female seborrhea. High doses of CPA are usually prescribed to men with inoperable prostate cancer, a condition that leads to excessive hair growth (hirsutism) or male-to-female transsexual hormonal therapy.
Researchers at the Universities of Bristol, Cambridge, and the National University of Singapore conducted the study, which was published Friday in Scientific Reports. They looked at four studies comprising a sample of more than 8 million patients, assessing the evidence of the association between CPA and incidence of meningioma.
More than 165,900 patients were identified as taking CPA at varying dose amounts.
Lead author Keng Siang Lee of the University of Bristol said, “The cause of meningiomas is controversial but there is strong evidence to suggest a plausible role for sex hormones in the onset of meningioma.”
“We know it has a predilection for females, especially after puberty. Furthermore, fluctuations in meningioma growth during the menstrual cycle, pregnancy, and breastfeeding have also been well-documented,” he added. “We are also aware of the well-characterized distribution of progesterone, estrogen, and androgen receptors in certain meningiomas located at the base of the skull.”
“In light of these results, prescription of high-dose cyproterone acetate, especially for off-label indications, should be considered carefully,” Siang Lee added. “Additionally, we suggest that routine screening and meningioma surveillance by brain MRI offered to patients prescribed with cyproterone acetate is likely a reasonable clinical consideration if given at high doses for long periods of time.”
He noted, “However, our study underscores the current limited evidence about the risk of intracranial meningioma associated with low dose cyproterone acetate. It is still unknown whether or not cyproterone acetate below a certain threshold may be completely safe in terms of the risk of meningioma. The results obtained herein suggest the necessity for further clinical research on intracranial meningioma associated with cyproterone acetate.”
