An 82-year-old patient was diagnosed after a normocytic-normochromic anemia due to neoplasm of the right colon.
Both histological and cytological studies diagnosed MM.
After an exhaustive extension study, including abdominal CAT scan, abdominal ultrasound, dermatological examination (including exeresis and right-sided exploration), hemithorax pracolectomy, and anorectal exploration, were ruled out.
The anatomopathological study of the resection specimen confirmed the presence of an ulcerated polypoid MM measuring 11 cm in diameter at the ascending colon, located in the submucosa and focally in the muscular layer.
Numerous tumor cells contained melanine and immunohistochemical study was positive for S-100 protein and HMB45.
Of the 30 lymph nodes resected, 2 had metastases.
The patient followed a correct postoperative course and was alive without evidence of disease at 4, 5 years after surgery.
