What were we already knowing on the subject?
Chlormadinone acetate is a synthetic progestogen which has a powerful progestogen activity with 2 mg, 5 mg or 10 mg dosages.
The known risk factors for meningioma are age, feminine gender, type 2 neurofibromatosis, exposure to ionizing radiation, endogenous sex hormones and progestins. A possible link between sex hormones and meningiomas has long been known on the basis of several arguments: a female predominance with a high women-man ratio, cases of acceleration of growth during pregnancy and decrease after childbirth, an influence of the menstrual cycle on the clinical expression of certain meningiomas, the presence of progesterone receptors in 60 % of meningiomas, their more important expression in women and their expression in the dura-mother and finally, a proven link with certain progestins such as cyproterone acetate and suspected with others.
Several cases of intracranial meningiomas were reported during prolonged exhibitions to chlormadinone acetate for several years with some a volume reduction of the tumor when stopping treatment.
What does the study bring again?
This study confirms a strong association and dose-dependent between the use of chlormadinone acetate and the meningioma treated with surgery or radiotherapy.
The absolute risk of meningioma in women who have used chlormadinone acetate for many years, for example 10 mg / day for 5 to 30 years in the treatment of endometriosis, is 1/1000 people-years.
As with cyproterone acetate (Androcur), the meningiomas located in the anterior and average part of the skull base were particularly associated with prolonged exposure to chlormadinone acetate; The risk decreased after stopping Chlormadinone acetate.
All the elements characterize a causal relationship even if the underlying biological mechanism is not yet completely known.
