SURAMIN IN ADRENOCORTICAL CANCER - LIMITED EFFICACY AND SERIOUS TOXICITY

OBJECTIVE No satisfactory treatment for adrenocortical carcinoma (ACO) is available. We investigated the efficacy and toxicity of suramin in the treatment of metastatic ACC since suramin has been recently repor ted to be active as a single agent therapy for patients with ACC and p rostatic carcinoma. DESIGN We collected data on 9 patients with metast atic ACC treated with suramin in four centres in Germany between 1987 and 1992. PATIENTS Nine patients (5 women, 4 men; age range 32-67 year s) were included. Biochemical evidence of steroid excess was found in 6/9, in three leading to clinical symptoms (hypertension, hyperglycaem ia, hirsutism, gynaecomastia). MEASUREMENTS Tumour responses were asse ssed by radiological and biochemical evaluation. Other investigations included regular measurements of blood cell counts, coagulation, hepat ic and renal function parameters, and serum suramin concentrations. RE SULTS The patients received; cumulative doses ranging from 8.2 to 30.2 g suramin over periods of 1-15 months. 3/9 achieved a partial respons e, 2/9 disease stabilization and 4/9 experienced progressive disease. Tumour responses were transient. Suramin treatment was without direct influence on steroid excess. Serious side-effects included coagulopath y (6/9), thrombocytopenia (6/9), polyneuropathy (2/9) and allergic ski n reactions (4/9); the death of two patients was possibly related to s uramin therapy. Both toxicity and tumour response were strongly associ ated with serum level or cumulative dose of suramin. CONCLUSIONS (1) S uramin is of antineoplastic efficacy in the treatment of metastatic ad renocortical carcinoma. (2) The clinical use of suramin is limited by a narrow therapeutic window with the risk of serious and possibly leth al toxicity at one extreme, and loss of efficacy at the other. Strict monitoring of suramin serum levels is mandatory aiming at levels betwe en 200 and 250 mg/l. Suramin should not be considered as first-line tr eatment for metastatic adrenocortical carcinoma. (3) To improve treatm ent options in adrenocortical carcinoma as well as for further investi gation on the usefulness of suramin, controlled prospective trials are urgently needed.