Malignant melanoma in inflammatory bowel disease.

Malignant melanoma occurred in 11 patients with inflammatory bowel disease (IBD). Six cases occurred in patients with ileocolitis, two in regional enteritis, one in granulomatous colitis, and two in patients with ulcerative colitis. The mean age at development of IBD was 24 yr, and at development of melanoma was 40 yr: the mean duration from onset of IBD to development of melanoma was thus 16 yr. All patients for whom complete information was available, except two, had received steroids and azulfidine for approximately a decade, as well as blood transfusions, usually multiple, and on repeated occasions. Six of the 11 patients had undergone one to seven prior operations (mean 3.5). All patients had wide radical excision of the melanoma, with or without concomitant or subsequent nodal dissection. Two patients (ages 25 and 36 yr) died rapidly from widely disseminated malignant melanoma. These cases may be coincidental, or else there may be an association between IBD and melanoma, related to immunosuppression either from the disease itself, from the medical and surgical therapy, and/or from x-ray exposure.