Crohnʼs Disease, Malignant Melanoma, and Churg-Strauss Syndrome: A Treatment Dilemma

Abstract

A 71-year-old man with Churg-Strauss disease on low-dose prednisone (prior azathioprine use), diabetes, atrial fibrillation, and diverticular disease presented with hematochezia, pain with defecation, & increased stool frequency. He denied abdominal pain, fever, nausea, emesis, weight loss, constipation, joint pains, skin rash or eye pain. Vital signs were normal, abdomen was soft, non-tender, non-distended, and rectal examination revealed perianal irritation and significant pain without fistulae. Laboratory studies revealed elevated CRP of 92.8 mg/L (normal C. difficile, Shigella PCR and stool culture. A CT abdomen revealed 5-10 cm concentric wall thickening in the sigmoid colon with associated pericolonic mesenteric hyperemia. Colonoscopy revealed nodularity and irregularity in the rectum and an inflammatory stricture in the sigmoid colon with deep ulcerations, and pathology revealed active chronic colitis with ulceration. Of note, a colonoscopy 5 months prior was normal. Treatment with aminosalicylates was unsuccessful and due to unclear diagnosis and concern for malignancy, laparoscopic sigmoid resection with primary anastomosis was performed. Surgical pathology showed moderately active chronic colitis with creeping fat, stricture formation, transmural chronic inflammation, and granulomas consistent with Crohn's disease. Six months later, he developed recurrent rectal bleeding and colonoscopy revealed moderately ulcerated rectal mucosa and mild inflammation of his colonic anastomosis consistent with moderately active Crohn's disease. In the interim, he underwent excision of a mole on his back and pathology was consistent with malignant melanoma. Therefore, the decision was made to defer anti-TNF therapy and the patient was treated with vedolizumab, a gut selective antiintegrin molecule. In addition to typical dermatologic manifestations such as pyoderma gangrenosum and erythema nodosum, patients with inflammatory bowel disease (IBD) are at increased risk for non-melanoma skin cancers and malignant melanoma. A meta-analysis revealed that IBD was associated with an increased risk of malignant melanoma, independent of treatment with biologic therapy, and is increased with anti-TNF treatment and immunomodulatory medications. In contrast, since vedolizumab selectively blocks gut leucocyte trafficking, it is likely to have lower systemic immunosuppression and lower risk for melanoma.