Testotoxicosis proved by immunohistochemical analysis and successfully treated with cyproterone acetate.

We present a case of testotoxicosis diagnosed on the basis of immunohistochemical investigation of the testis. The patient was treated with the antiandrogen cyproterone acetate at a dose of 70-130 mg/m2/day. Clinical and biochemical features are consistent with the diagnosis of testotoxicosis. The long-term experience with cyproterone acetate had been generally satisfactory. There are, to our knowledge, no reports on cyproterone acetate treatment of testotoxicosis.