EXPRESSION OF P-GLYCOPROTEIN IN RELATION TO CLINICAL MANIFESTATION, TREATMENT AND PROGNOSIS OF ADRENOCORTICAL CANCER

The presence of P-glycoprotein, associated with multiple drug resistan ce and present in the normal adrenal cortex, was studied in 15 cases o f adrenocortical carcinoma. P-glycoprotein was found in eight tumours; no correlation was found with clinical presentation, steroid producti on or histological index. 10 patients received mitotane. Remarkably, 3 patients with P-glycoprotein-positive tumours achieved complete remis sion. On the other hand, 2 patients with P-glycoprotein-negative tumou rs showed progression of the disease despite mitotane treatment. These findings suggest that the expression of P-glycoprotein in adrenocorti cal carcinoma is not related to clinical manifestations, steroid produ ction, histological index or response to mitotane therapy.