It was reported in The Guardian that millions of women around the world who use certain hormone drugs for contraception and to manage conditions such as endometriosis may have a “raised risk of rare, usually benign, brain tumours”, according to researchers.
It was noted that, “scientists found that prolonged use of certain progestogen medications was linked to a greater risk of meningioma, which are tumours (usually noncancerous) that form in tissues around the brain.”
Meningiomas
According to the British Medical Journal:
“Meningiomas account for 40% of primary tumours of the central nervous system. The incidence of meningioma in the United States is 9.5 per 100 000 person years. Meningiomas are mostly slow growing, histologically benign tumours but can nevertheless compress adjacent brain tissue and thus patients may require surgical decompression.”
The article goes on to say that the link between, “female sexual hormones, in particular progesterone, and intracranial meningioma is biologically plausible. “
According to the Guardian, there were two oral pills, medrogestone and promegestone, which were particularly linked to meningioma. It was said that there was a “4.1 and 2.7-fold greater risk of meningioma respectively; and medroxyprogesterone acetate, a contraceptive injection sold as Depo-Provera, was linked to a 5.6-fold higher risk.”
Further studies are needed
The researchers have called for more studies into the safety of the hormones, especially injectable medroxyprogesterone acetate. It was said that, the injections were rarely used in the UK and the rest of Europe, but that globally 74 million women receive them, with the writers suggesting that this meant that, “the number of attributable meningiomas may be potentially high”.
It was also noted that based on UK cancer data registries, about four in every thousand 30-year-old women would be expected to develop a meningioma by the age of 80. This means that if, as the BMJ article suggests, using medroxyprogesterone acetate for more than a year increases the risk about fivefold, that figure could rise to 20 in every thousand.
It is a small risk
Although the study does suggest that there is a raised risk meningiomas, the risk is still seen as very small. Prof Paul Pharoah, who was described as a cancer epidemiologist who spent 20 years at the University of Cambridge studying hormone-related cancers before setting up a lab in California, at the Cedars-Sinai hospital, was reported as saying that, “there were many different types of progestogens and no association with meningioma was found for those commonly used in the UK.”
Pharoah went on to say:
“it is important that women do not stop using their birth control pills without consulting their doctor.”
