mart-1-antigen and Adenocarcinoma--Clear-Cell

A group of lesions show morphologic and immunophenotypic evidence of differentiation toward a putative perivascular epithelioid cell. These so-called PEComas include angiomyolipoma, lymphangiomyoma, lymphangioleiomyomatosis, renal capsuloma, clear cell myomelanocytic tumor of the falciform ligament/ligamentum teres, and clear cell "sugar" tumor. PEComas are characterized by strong immunoreactivity with the HMB45 antibody and variable expression of muscle markers. This family of lesions may be composed of a spectrum of cells from epithelioid to spindle cells with clear to granular eosinophilic cytoplasm. One member of this family, composed of epithelioid cells with glycogen-rich clear cytoplasm, is descriptively called a clear cell "sugar" tumor. This tumor, originally described in the lung, is being recognized increasingly in extrapulmonary sites. We report a case of a primary extrapulmonary clear cell "sugar" tumor occurring in the right breast of a 16-year-old girl. The tumor was composed of clear epithelioid cells with abundant glycogen and distinct cell borders. The tumor showed strong immunoreactivity with HMB45 antibody and Melan-A. There was focal vimentin staining. In addition, there was diffuse and strong nuclear staining for progesterone receptor. Antibodies to actins, S-100 protein, cytokeratins (AE1/AE3 and CAM5.2), desmin, and estrogen receptor were negative. The tumor was completely excised, and the patient is well without evidence of disease 9 months postexcision.

Topics: Adenocarcinoma, Clear Cell; Adolescent; Antigens, Neoplasm; Biomarkers, Tumor; Breast Neoplasms; Cytoplasm; Female; Glycogen; Humans; Immunohistochemistry; MART-1 Antigen; Melanoma-Specific Antigens; Neoplasm Proteins

HMB-45-positive clear-cell epithelioid tumor arising in the ligamentum teres hepatis of a 13-year-old Japanese girl is described. The well-defined tumor was completely removed and measured 9 x 7 x 6 cm. Cut sections showed a tan-white, homogeneous appearances with no hemorrhage or necrosis. The tumor was composed of nests or sheets of polygonal or oval-shaped cells rich in clear or finely granular cytoplasm. Capillary network was well developed, and sinusoid vessels were often seen with occasional perivascular hyalinization. There was moderate nuclear atypia but mitotic figures were absent. Periodic acid-Schiff stain showed a large amount of glycogen digested by diastase. Immunohistochemical stains for smooth muscle actin, Melan-A, and HMB-45 were positive in most of the tumor cells. Stains for vimentin, muscle actin, and HAM56 were focally positive, whereas stains for desmin, cytokeratin, epithelial membrane antigen, S-100, CD34, CD68, CD99, neurofilament proteins, and estrogen/progesterone receptors were negative. Ultrastructurally, the cytoplasm contained a considerable number of mitochondria, monoparticipate or membrane-bound glycogen, and longitudinally oriented thin filaments with focal condensations and subplasmalemmal densities. The histopathology of the present case, originally interpreted as epithelioid leiomyoma, was consistent with clear cell "sugar" tumors. The present case may indicate ubiquitous distribution of clear cell "sugar tumors" of which histogenesis remains unknown but is presumed to be of perivascular epithelioid cell origin.

Topics: Actins; Adenocarcinoma, Clear Cell; Adolescent; Antigens, Neoplasm; Epithelioid Cells; Female; Humans; Immunohistochemistry; Ligaments; Liver Neoplasms; MART-1 Antigen; Melanoma-Specific Antigens; Microscopy, Electron; Neoplasm Proteins

The antibody to the melanoma antigen recognized by T cells (anti-MART-1, clone M2-7C10) is a newly described antibody to a transmembrane protein previously detected only in normal skin melanocytes, retinal tissue, and malignant melanoma (MM). This antibody is the basis for ongoing immunotherapy protocols at the National Institutes of Health/National Cancer Institute. HMB-45, an antibody directed against a premelanosome glycoprotein, although used predominantly for the diagnosis of MM, has shown consistent staining in angiomyolipoma (AML), lymphangiomyoma/lymphangiomyomatosis (LAM), and clear cell sugar tumor (CCST), a group of tumors proposed to be related on the basis of their common perivascular epithelioid cells, which exhibit various degrees of smooth muscle differentiation, melanogenesis, and intracytoplasmic membrane bound granules. To compare the immunoreactive patterns of anti-MART-1 with those of HMB-45, we performed avidin-biotin immunoperoxidase testing on nonmelanocytic neoplasms (AMLs, LAMs, CCSTs) known to express HMB-45. Microwave pretreatment was necessary for anti-MART-1 staining on paraffin-embedded material. Our results showed that all of the 10 cases of AML were immunoreactive for both anti-MART-1 and HMB-45; that all of the 4 cases of LAM were positive for HMB-45, with 1 of the 4 reacting with anti-MART-1; and that 3 of the 4 cases of CCST expressed HMB-45, whereas 1 of the 4 was positive for anti-MART-1. Our findings lent additional support to previous studies that proposed a relationship between AML, LAM, and CCST. Anti-MART-1 and HMB-45 share similar specificities for these nonmelanocytic tumors, but the former seems to be a less sensitive marker for these lesions. In similar circumstances, anti-MART-1 and HMB-45 are potentially useful clinical markers.

Topics: Adenocarcinoma, Clear Cell; Angiomyolipoma; Antigens, Neoplasm; Humans; Immunoenzyme Techniques; Lymphangioleiomyomatosis; MART-1 Antigen; Melanoma-Specific Antigens; Neoplasm Proteins; T-Lymphocytes; Tumor Cells, Cultured