Malignant melanoma arising from an end ileostomy.

A 65-year-old woman with a history of proctocolectomy and end ileostomy for ulcerative colitis was referred to our clinic with a slowly growing mass around her ileostomy. She did not report any systemic symptoms. On examination, an exophytic mass was observed around her ileostomy and hard lymph nodes palpated in her groins bilaterally. Punch biopsy of the lesion established a diagnosis of invasive melanoma. Positron emission tomography revealed regional metastatic lymphadenopathy in the right axilla and both groins. There was no evidence of distant metastatic disease. The patient then underwent wide local excision of her ileostomy with bowel resection and ileostomy re-siting, bilateral complete ilioinguinal lymphadenectomy and a right Level III axillary dissection. She is doing well postoperatively and receiving adjuvant systemic therapy with BRAF and MEK inhibitors, now 17 months later with no signs of recurrent disease.