Endocrine Abstracts

Introduction: There are many side effects caused by mitotane and several are registered at drug levels lower than therapeutical doses.

Aim: We observed the mitotane side effects in patients treated for adrenal cancer.

Materials and methods: This is a retrospective study in adrenal tumors.

Results: Out of 56 patients included in a database with adrenal tumors, we found eight patients (14.25%) with adrenal cancer and histological confirmation of the disease. The mean age was 53.57 years. Twenty-five percent of patients were men. 62.5% of these patients were treated with mitotane and 25% of them with chemotherapy. All patients with adrenal disease had unilateral adrenal tumors (50% of them were on the left side). Twenty-five percent of patients did not have metastasis at the moment of adrenal surgery. The mitotane was started after the adrenal surgery from 2 months to 2 years. All the patients had adrenal insufficiency immediately after surgery because of the previous Cushing disease caused by the tumor itself, so this was not registered later as a side effect to mitotane. The adverse reactions to mitotane were registered from very low doses were mild digestive effects as nausea were registered in all patients treated with mitotane from the first days. One female patient had multiforme erythema 10 days after starting the therapy. After temporary arrest of the mitorane, the drug was re-initiated and no erythema was found. Sisty-six percent of patients treated with mitotane had hypercholesterolemia at a level under 3.3 mg/dl. At least then 6 months from starting the therapy 33% of patients had peripheral neuropathy, anemia, and the men hypogonadism and painful gynecomastia. All these reactions were registered at very low doses of mitotane, far from therapeutical window of efficiency. No correlations of the side effects were found to the initial size of the tumor, to the severity of the clinical phenotype before adrenalectomy, or to the Weiss score.

Conclusion: The mitotane in adrenal cancer is a useful drug but numerous adverse reactions are registered from the beginning of the therapy, thus close follow-up is necessary.