Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10721 (c-kit)
 6,575 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The incidence of retroperitoneal seminoma is much less than that of its gonadal counterpart. Accurate diagnosis of retroperitoneal seminoma is critical, because it carries an excellent prognosis due to its favorable response to radiation therapy and/or cisplatin-based chemotherapy. However, correctly diagnosing a retroperitoneal seminoma may be challenging, especially when the biopsy material is limited. The present study was conducted to evaluate histologic findings and immunohistochemical staining patterns in biopsy specimens of retroperitoneal seminoma and to compare their utility as diagnostic tools. Thirty biopsy specimens of retroperitoneal seminoma were assessed for histologic characteristics and immunohistochemical expression of OCT4, c-kit, placental-like alkaline phosphatase, and cytokeratin AE1/AE3. The clinical information, morphologic features, and staining intensities and the percentages of positively staining tumor cells were analyzed. The mean age of patients was 38 years. Lymphocytic infiltration and nucleolar prominence in tumor cells were found in all 30 cases (100%). The incidence of other histologic characteristics were as follows: fibrous septa/stroma in 80% (24 cases), clear tumor cell cytoplasm in 70% (21 cases), tumor necrosis in 60% (18 cases), cellular pleomorphism in 53% (16 cases), granulomatous inflammation in 50% (15 cases), distinct cell borders in 46% (14 cases), intercellular edema in 23% (7 cases), and syncytiotrophoblasts in 3% (1 case). The mean mitotic count was 3 (range 0 to 15) per 10 high-power fields. All 30 cases (100%) of retroperitoneal seminoma revealed moderate to strong nuclear OCT4 staining in more than 50% of tumor cells. Twenty-one cases (70%) showed membranous expression of c-kit by tumor cells, with moderate to strong staining intensity in most cases. Variable degrees of staining for placental-like alkaline phosphatase were identified in 23 cases (77%) with occasional background staining artifact. Six cases (20%) displayed a positive cytokeratin AE1/AE3 staining pattern with weak to moderate intensity. In conclusion, the most common histologic findings in limited biopsy specimens of retroperitoneal seminoma were lymphocytic infiltration and nucleolar prominence in tumor cell nuclei. OCT4 immunostaining, with its superior sensitivity and easy interpretation compared with other markers, is a powerful tool for confirming the diagnosis of retroperitoneal seminoma.
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PMID:Retroperitoneal seminoma in limited biopsies: morphologic criteria and immunohistochemical findings in 30 cases. 1672 57

Accurate diagnosis of mediastinal seminoma is critical because of its favorable response to radiation therapy and/or cisplatin-based chemotherapy. Immunohistochemical staining for OCT4 has recently been validated as a powerful tool for detecting gonadal seminoma. However, discrepancies between the genetic alterations and immunoprofiles of mediastinal and testicular seminomas have been reported, raising the question of whether techniques that are useful in the diagnosis of gonadal seminoma are applicable to its mediastinal counterpart. The present study was conducted to evaluate the morphologic and immunohistochemical characteristics and chromosomal abnormalities of 12p in 23 primary mediastinal seminomas and to compare their applicability as diagnostic tools. Dual-color fluorescence in situ hybridization (FISH) analyses for chromosome 12p and immunostains for OCT4, c-kit, placental-like alkaline phosphatase, CD30, and a panel of cytokeratins, including cytokeratin AE1/AE3 (AE1/3), high molecular weight cytokeratin (34betaE12, HMWCK), CAM5.2, cytokeratin 7 (CK7), cytokeratin 20 (CK20), and epithelial membrane antigen were performed. Lymphocytic infiltration was found in all 23 cases (100%). The incidence of other histologic characteristics were as follows: fibrous septa/stroma (21 cases, 91%), prominent tumor cell nucleoli (21 cases, 91%), clear tumor cell cytoplasm (20 cases, 87%), distinct tumor cell borders (20 cases, 87%), granulomatous inflammation (17 cases, 74%), cellular pleomorphism (10 cases, 43%), necrosis (8 cases, 35%), prominent cystic change (2 cases, 8%), intercellular edema (1 case, 4%), and syncytiotrophoblasts (1 case, 4%). The mean mitotic count was 4.4 (range 0 to 16) per 10 high-power fields. Moderate to strong nuclear OCT4 staining was identified in all 23 cases (100%). Seventeen tumors (74%) showed membranous expression of c-kit, with variable staining intensity and percentages. Weakly to moderately intense immunostaining for placental-like alkaline phosphatase was identified in 10 cases (43%) with occasional background staining artifact. The incidences of positive staining were 43% for AE1/3, 39% for HMWCK, 48% for CAM5.2, 39% for CK7, and 9% for epithelial membrane antigen, respectively. In most cases, these epithelial markers highlighted only a small proportion of tumor cells with variable intensities. Immunostaining for CD30 and CK20 was completely negative in all seminomas. Twenty-two seminomas (96%) revealed chromosome 12p abnormalities, including 12p amplification in 20 cases (87%) or i(12p) in 15 cases (65%). Lymphocytic infiltration is the most common histologic feature observed in primary mediastinal seminoma and both OCT4 immunostain and FISH for 12p abnormalities can be very helpful in diagnosing mediastinal seminoma. The intense staining pattern of OCT4 and the high sensitivity of FISH make them superior to other auxiliary diagnostic utilities for detecting seminoma. In addition, the incidences of cytokeratin expression of primary mediastinal seminoma are similar to those of its gonadal counterpart and pathologists must exercise caution in the interpretation of epithelial markers in mediastinal neoplasms.
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PMID:Primary mediastinal seminoma: a comprehensive assessment integrated with histology, immunohistochemistry, and fluorescence in situ hybridization for chromosome 12p abnormalities in 23 cases. 1816 82