Endocrine Abstracts

Introduction: Megestrol acetate (MA) has been used in various cancers as a palliative agent to treat cancer cachexia. It has glucocorticoid activity and can induce significant secondary adrenal suppression. We designed this study to determine the extent of adrenal insufficiency in cancer patients receiving MA and find out whether ther was any predictive factor for this.

Methods: Thirty-one patients (11 females and 20 males, aged 48–83 years) who were receiving MA took part in this study. They were evaluated for HPA axis; before the initiation and 1 month later. Serum concentrations of TSH, ACTH, free T₄, cortisol were measured in samples obtained at 0700 h, at baseline and 1st month. Standart ACTH (250 mg) stimulation test was performed if cortisol levels were below 18 μg/dl at any time.

Results: 1 month after drug initiation, 32% of patients were accepted as adrenal insufficient. There wasn’t any correlation between the basal cortisol, ACTH levels, any biochemical parameter and overall survival. There was negative correlation between 1 month cortisol levels and survival time (P=0.04) If cortisol levels were lower at month of theraphy survival time was longer. Cox regression analysis showed that patients having lower cortisol levels at first month had 98% lower risk of death compared to patients having higher cortisol levels (P=0.02: OR 0.12 (0.02–0.75)).

Conclusion: It is important to be aware of the effects of MA on adrenal functions and evaluate adrenal functions especially during episodes of infection or after withdrawal of MA therapy since this may require prompt corticosteroid treatment.