Variant on Manifestation of Duodenal Metastasis 26 Years after Initial Diagnosis of Primary Cutaneous Melanoma.

Malignant duodenal neoplasms are relatively rare, and the diagnosis is often delayed because of their vague and nonspecific symptoms. We report the case of a 79-year-old female who had a medical history of malignant melanoma of the cheek that had initially been diagnosed at 53 years of age. Work-up revealed severe stenosis of the duodenum caused by a large mass with ulceration at the tip of its mucosal surface. Tumor biopsy led to a histological diagnosis of extremely poorly differentiated carcinoma, but it was impossible to determine whether the lesion was a primary neoplasm or represented secondary involvement. Pancreatoduodenectomy was performed, and the surgical specimen showed a protuberant tumor in the nonampullary region of the second portion of the duodenum. Final diagnosis of metastatic duodenal melanoma was made by immunohistological examination. She is currently alive without recurrence 28 months after the surgical treatment.