mart-1-antigen and Bone-Neoplasms

Malignant melanoma is one of the most common malignant diseases of the gastrointestinal tract. It has been reported that the malignant melanoma metastasizes not only to the small intestine due to the abundant blood supply, but also to the stomach, colon, and esophagus. Gastrointestinal metastasis is usually suspected depending on the clinical symptoms, as well as based on radiological or endoscopic findings. Imunohistochemical stains, such as Melan-A/Melanoma antigen recognized by T cell-1 or human melanoma black-45, are useful for confirming the diagnosis of malignant melanoma. A 44-year-old male received an operation due to a malignant melanoma at the left thumb two years ago. On the national health screening endoscopy, a submucosal tumor with hyperemic change on the top was found. The final diagnosis was a metastatic malignant melanoma in the stomach, pancreas, and pelvic bone. We recommend that endoscopists should consider the potential malignancy of subepithelial tumor with mucosa change, despite the tumor size being less than 1 cm.

Topics: Adult; Bone Neoplasms; Endoscopy, Digestive System; Gastrointestinal Neoplasms; gp100 Melanoma Antigen; Humans; Male; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Melanoma, Cutaneous Malignant; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Skin Neoplasms

Osteoid malignant melanoma is a rare type of melanoma described in humans and dogs with some areas of bone differentiation. In this tumour, the origin of the bone matrix remains unclear. We report one case of this variant with, for the first time, a cutaneous origin in a dog. Malignant melanomas are aggressive tumours. Amelanotic tumours are sometimes difficult to recognize as they require immunohistochemical evaluation for an adequate diagnosis and we have used anti-vimentin, S100, and melan A antibodies for identification. Melan A is less sensitive but more specific than S100 in identifying amelanotic melanomas. This tumour was positive for vimentin, S100 and melan A, including the areas of osteoid. These results suggest osteoid differentiation of tumour cells rather than induced stromal metaplasia.

Topics: Animals; Antigens, Neoplasm; Biomarkers, Tumor; Bone Neoplasms; Dog Diseases; Dogs; Immunohistochemistry; Male; MART-1 Antigen; Melanoma; Neoplasm Proteins; S100 Proteins; Vimentin

Osteocartilaginous metaplasia is known to occur rarely in melanomas, particularly in subungual melanomas. We present a case of a calcified subungual soft tissue tumour in which biopsy of the lesion showed malignant round and spindle-shaped tumour cells, many of which were associated with the formation of cartilage and osteoid-like material. Subsequent resection showed clear histological evidence of a subungual melanoma. Tumour cells expressed S100, melan-A and neurone-specific enolase but were negative for HMB45. Diagnostic radiological and histological features and the nature of the osteocartilaginous differentiation within this lesion is discussed.

Topics: Antigens, Neoplasm; Biomarkers, Tumor; Biopsy; Bone Neoplasms; Cartilage; Diagnosis, Differential; Fingers; Humans; Magnetic Resonance Imaging; Male; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Osteochondroma; Osteosarcoma; Phosphopyruvate Hydratase; Soft Tissue Neoplasms; Tomography, X-Ray Computed

Topics: Adrenal Gland Neoplasms; Antibodies, Neoplasm; Antibody Specificity; Antigens, Neoplasm; Biopsy, Needle; Bone Neoplasms; Humans; Liver Neoplasms; Lung Neoplasms; MART-1 Antigen; Melanoma; Neoplasm Metastasis; Neoplasm Proteins; Pancreatic Neoplasms