MERKEL CELL-CARCINOMA ARISING AFTER THERAPEUTIC IMMUNOSUPPRESSION

Azathioprine and cyclosporin have been used as immunosuppressants for many years, but long-term use has also been associated with neoplasia, We report three cases of rapidly fatal Merkel cell carcinoma in patie nts who had been treated with azathioprine for many years either for r heumatoid arthritis or following organ transplantation. Two of these p atients had also received cyclosporin, We suggest that Merkel cell car cinoma may be seen more commonly in immunosuppressed patients than in the normal population and that the oncogenic potential of azathioprine and cyclosporin should be borne in mind when prescribing these drugs.