1/14. Chondrosarcomatous differentiation in metastatic deposit of serous papillary cystadenocarcinoma.A rare case of serous papillary cystadenocarcinoma of the ovary showing chondrosarcomatous differentiation in a metastatic deposit late in the clinical course is reported. A 49-year-old female underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy for bilateral ovarian tumors. Histological diagnosis was serous papillary cystadenocarcinoma of both ovaries with lymph node metastasis. After six courses of chemotherapy, she was confirmed to be in complete remission following a second laparotomy. Following additional chemotherapy, a third laparotomy disclosed swollen left inguinal lymph nodes. In one of these nodes, approximately 5.0 cm in greatest diameter, the predominant histological features were: chondrosarcoma of the bone and soft tissue, with small foci of serous papillary adenocarcinoma and squamous epithelium. A histological transition between mesenchymal and epithelial areas was identified. Immunohistochemical positivity for broad-spectrum cytokeratin (AE1/AE3), vimentin, epithelial membrane antigen, and S-100 protein was observed in both chondrosarcomatous and epithelial areas. The current evidence may suggest that the chondrosarcomatous differentiation was derived from the metastatic epithelial component.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/14. Primary chondroid melanoma.BACKGROUND: Malignant melanoma is notorious for the wide range of histologic patterns it can assume, among the least frequent of which is chondroid melamona. methods: Two cases of primary chondroid melanoma of the distal lower extremity were studied. Tissue for light microscopy was fixed in formalin, embedded in paraffin, and processed routinely. In one case, transmission electron microscopy and immunohistochemical evaluation were performed. RESULTS: Both cases exhibited melanoma in-situ, a conventional (non-chondroid) invasive component, and areas of chondroid differentiation, as confirmed by strongly positive staining with alcian blue at pH 2.5 and Safranin O. Immunohistochemically, one case expressed S-100 protein and vimentin, and did not express gp100 (HMB-45), tyrosinase, MART-1, the Mel-5 antigen, the NKI/C3 antigen, CD45Ro, cytokeratin, or desmin. Electron microscopy of the chondroid component revealed occasional tumor cells with rare, membrane-bound, electron-dense organelles; the extracellular compartment showed amorphous ground substance consistent with cartilaginous differentiation. CONCLUSIONS: Chondroid change in the absence of osteogenic differentiation is extremely rare in malignant melanoma. melanoma should be considered in the differential diagnosis of primary cutaneous neoplasms exhibiting cartilaginous differentiation.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
3/14. True pulmonary carcinosarcoma (squamous cell carcinoma and chondrosarcoma). A case report.True pulmonary carcinosarcoma (squamous cell carcinoma and chondrosarcoma) originating in the right lower lobe in a 62-year-old Japanese male is reported. The tumor, measuring 5.5 x 3.5 x 3.5 cm, was markedly necrotic and its apex protruded into the bronchial lumen. light microscopy showed that the tumor was composed of squamous cell carcinoma with sarcomatous spindle or polygonal cell proliferation and true chondrosarcoma. Immunohistochemically, the cytoplasm of numerous cells of the squamous cell carcinoma component was stained with anti-cytokeratin (PKK 1) and the cytoplasmic membrane with anti-epithelial membrane antigen (EMA). Although sarcomatous regions were stained with anti-vimentin (vimentin) and no tumor cells were reactive for EMA, a few tumor cells were positive for PKK 1. The cytoplasm of numerous chondrosarcoma cells was positively stained for vimentin and S-100 protein. Based on these findings, we concluded that the present tumor was a true carcinosarcoma composed of squamous cell carcinoma with sarcomatous regions and true chondrosarcoma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/14. Malignant mixed mullerian tumor of the ovary. Report of a case studied by immunohistochemistry.A case of malignant mixed mullerian tumor of the ovary in a 57-year-old woman is reported along with the results of an immunohistochemical study. The tumor, measuring 16 x 10 x 9 cm, was composed predominantly of adenocarcinoma with a smaller amount of anaplastic carcinoma as an epithelial component and chondrosarcoma, liposarcoma, fibrosarcoma and rhabdomyoblasts as mesenchymal elements. immunohistochemistry using paraffin sections demonstrated cytokeratin (CK) and epithelial membrane antigen (EMA), generally regarded as epithelial markers, not only in the epithelial component but also in chondrosarcoma cells. vimentin and desmin, generally regarded as mesenchymal markers, were exhibited partly in carcinoma cells as well as in mesenchymal elements. Positive staining for S-100 protein was obtained not only in chondrosarcoma and liposarcoma cells, but also partly in adenocarcinoma cells. This intricate immunohistochemical picture reflected the histologic findings. It is noteworthy that both carcinoma cells and chondrosarcoma cells demonstrated simultaneous expression of CK, EMA, vimentin, desmin and S-100 protein. This somewhat unusual antigen expression by tumor cells may indicate a change in the nature of tumor cells due to microenvironmental factors.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
5/14. Malignant lymphoma with myxoid stroma: a new pattern in need of recognition.We report a case of malignant lymphoma in the soft tissues exhibiting prominent myxoid stromal changes and cord-like cellular arrangement, mimicking the architectural as well as cytological features of myxoid chondrosarcoma, except for the absence of tumour lobulation. The only clue to the possible lymphomatous nature of the lesion was the past history of lymphoma. Immunohistochemical studies showed that this represented a B-cell lymphoma, staining positively for leucocyte common antigen and five B-lineage markers L26, MB2, B1 (CD20), B4 (CD19) and To15 (CD22). We conclude that malignant lymphoma should not be excluded from consideration when one encounters a myxoid tumour.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/14. Pleomorphic ("dedifferentiated") chondrosarcoma. Report of a case initially examined by fine needle aspiration biopsy.Fine needle aspiration (FNA) biopsy of a predominantly radiolucent, destructive lesion of the right distal femoral metaphysis of a 69-year-old man produced smears containing spindle-shaped cells with cytologic features consistent with a malignant fibrous histiocytoma. This initial diagnosis was supported by immunoperoxidase staining, which was strongly positive for vimentin and alpha-1-antichymotrypsin, focally positive for S-100 protein and negative for desmin, muscle-specific actin, keratin, carcinoembryonic antigen and epithelial membrane antigen. Subsequent surgical resection revealed a lesion with a predominance of malignant fibrous histiocytoma-type regions; however, focal microscopic areas contained a low-to-medium-grade cartilaginous component. The final diagnosis rendered was thus pleomorphic or so-called "dedifferentiated" chondrosarcoma. This rare lesion should be included in the differential diagnosis of malignant spindle-cell lesions of bone assessed by FNA biopsy.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
7/14. carcinosarcoma of the colon. Report of a unique case with light and immunohistochemical studies.A unique case of carcinosarcoma of the colon is reported. The tumor invaded the bowel wall deeply, metastasized widely, resisted multi-agent chemotherapy, and caused the patient's death 4 years later. The tumor was composed of adenosquamous carcinoma admixed with sarcoma showing osseous, cartilaginous, and nonspecific spindle-cell differentiation. Although carcinoembryonic antigen appeared limited to carcinoma cells, cytokeratin immunoreactivity was observed in both carcinoma and sarcoma cells. Like carcinosarcomas at other body sites, the finding of cytokeratin in sarcoma cells supports partial epithelial differentiation in this component, likely retained from carcinoma precursor cells.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/14. Periosteal osteosarcoma and parosteal chondrosarcoma evaluated by double immunohistochemical staining. Report of 2 cases.Differentiation of periosteal osteosarcoma and parosteal (periosteal) chondrosarcoma by conventional histology may be difficult. One case each of clinically and histologically proven periosteal osteosarcoma and parosteal chondrosarcoma were evaluated by a double-immunohistochemical staining method using proliferating cell nuclear antigen (PCNA) and S-100 protein (S-100). Conventional histology showed proliferation of both osteoblastic and chondroblastic cells in the periosteal osteosarcoma, while there was a growth of only chondroblastic tumor cells in the parosteal chondrosarcoma. Immunohistochemical studies indicated that the nuclei of chondroblastic cells recognized by S-100 were PCNA-negative, while osteoblastic stromal cells were PCNA-positive in the periosteal osteosarcoma. In contrast, chondroblastic cells in the parosteal chondrosarcoma were both S-100- and PCNA-positive. Our findings suggest that periosteal osteosarcoma is characterized by the proliferation of osteoblastic stromal cells, whereas parosteal chondrosarcoma is characterized by the proliferation of chondroblastic cells. This method of double immunohistochemical staining, using PCNA and S-100, may be useful in differentiating these chondroblastic tumors.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/14. Parachordoma of the buttock: an immunohistochemical case study and review.We report a case of parachordoma occurring in the buttock of a 43-year-old man, and review 20 cases of parachordoma reported in the English literature. The tumor in our case was grossly 3 cm in dimension, solid, lobulated and grayish-white in color. Microscopically, the tumor consisted of epithelioid and spindle cells, and fibromyxoid stroma. The epithelioid cells were immunohistochemically positive for vimentin, S-100 protein, neuron-specific enolase, keratin, carcinoembryonic antigen and epithelial membrane antigen, and negative for HMB45. These findings are similar to those for chordoma rather than extraskeletal myxoid chrondrosarcoma. Although the etiopathogenesis of parachordoma remains obscure, schwann cells or some other neuron-related cell origin are suspected.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
10/14. Unusual mesenchymal and mixed tumors of the salivary gland. An immunohistochemical and flow cytometric analysis of three cases.Histological, immunohistochemical, and flow cytometric characteristics of three unusual parotid gland tumors are described. The patients were adult white men with carcinoma ex pleomorphic adenoma, true malignant mixed tumor, and primary parotid gland chondrosarcoma. The carcinoma ex pleomorphic adenoma showed evidence of simultaneous epithelial, myoepithelial, and mesenchymal differentiation by immunohistochemistry. The true malignant mixed tumor exhibited variable positivity for two keratins, vimentin, proliferating cell nuclear antigen, Ki67, and p53. The chondrosarcoma initially stained for vimentin, S100, muscle-specific actin, proliferating cell nuclear antigen, and Ki67, but it lost actin expression in its first recurrence, accompanied by more extensive Ki67 staining. dna ploidy varied from diploid to aneuploid with intratumoral variation in the carcinosarcoma. S-phase fractions ranged from 2.43% to 13.9%. The findings underscore the diversity of tumors that may be pathogenetically related to, and at times derived from, pleomorphic adenoma.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
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