Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0268596 (EMA)
 2,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Methotrexate produced the first remission in leukemia and the first cure of a solid tumor, choriocarcinoma. Methotrexate tightly binds to dihydrofolate reductase (DHFR), blocking the reduction of dihydrofolate to tetrahydrofolic acid, the active form of folic acid. Methotrexate also directly inhibits the folate-dependent enzymes of de novo purine and thymidylate synthesis. Resistance to methotrexate may develop as a result of elevated DHFR activity or defective transport of methotrexate into malignant cells. Increased DHFR enzyme levels may also result from amplification of the DHFR gene, which is now clinically significant in selected patients. Methotrexate is an active drug in the first-line treatment of gestational trophoblastic disease (GTD) and in metastatic squamous cell carcinoma of the cervix. Since the introduction of methotrexate chemotherapy for malignant GTD, most hospitals have reported almost 100% cure rates for patients with nonmetastatic disease using single-agent regimens. Patients with low-risk metastatic disease have been treated with methotrexate and folinic acid and over 50% complete remission rates have been reported. Patients with metastatic GTD who had one or more high-risk factors benefited from initial multiagent chemotherapy, rather than waiting for acquisition of drug-resistance to single-agent therapy to start multiagent treatment. Using multiagent combination chemotherapy such as MAC (methotrexate, actinomycin D, cyclophosphamide) or EMA-CO (etoposide, methotrexate, actinomycin D and cyclophosphamide, vincristine), most investigators have reported remission in approximately 60 to 80% of patients with high-risk metastatic GTD. Although the role of chemotherapy in carcinoma of the cervix has been limited for several reasons, trial of combination chemotherapy including methotrexate has been reported. However, it is still impossible to draw definite conclusions as to whether methotrexate combined with another clearly active drug may yield a superior response rate and survival.
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PMID:[Methotrexate in gynecologic oncology]. 897 93

A case of malignant neuroendocrine tumor presenting a huge mediastinal mass controlled with radiation therapy is reported. A thoracotomy was performed on a 57-year-old male and a mass was found to invade the trachea, main bronchus, and left atrium. The tumor was unresectable. Subsequently, cisplatin was administered, but the tumor grew in size and radiation therapy was recommended. The tumor responded well to thoracic irradiation (56 Gy) and disappeared. Three months later, lymph nodes metastases were noted in the retrocrural and upper abdominal paraaortic regions, but these were controlled again with palliative irradiation. Without further treatment, he survived free of disease for over 5 years. Specimens obtained during the thoracotomy showed that the tumor consisted mainly of small round cells with a rosette formation. Immunohistochemically the tumor was positive to NSE and slightly positive to keratin, but negative to LCA, L26, UCLH-1, EMA, Leu7, and chromogranin, suggesting a malignant tumor derived from neuroendocrine tissue.
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PMID:Malignant neuroendocrine tumor presenting a huge mediastinal mass controlled with radiation therapy. 986 8

Merkel cell carcinoma (MCC) is a malignant cutaneous neuroendocrine tumor which may be difficult to diagnose. It mostly occurs in old patients and the commonest sites are the skin of the head and neck and the extremities. MCC appears as a solitary violaceous dome-shaped nodule or indurated plaque. Histopathologic diagnosis may be difficult and three main patterns have been described. With immunohistochemistry studies, MCC express both epithelial (cytokeratins, EMA) and neuroendocrine (NSE, chromogranin, ...) markers. The tumor develops an aggressive course not unlike an aggressive melanoma. Local recurrence and regional lymph node metastases occur in 40 to 75% of cases. Long-term prognosis is unfavorable (3-year survival rate is 55%). Wide surgical excision associated with radiotherapy is the treatment of choice, regional lymph node metastases should be treated by lymph node excision and radiotherapy; chemotherapy should be used in systemic disease.
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PMID:[Merkel cell carcinoma]. 992 75

Rhabdoid tumor is a well-accepted clincopathologic entity among childhood renal neoplasms; similar tumors have been described in extrarenal locations. We present the clinicopathologic profile and the immunohistochemical features of a series of soft tissue rhabdoid tumors. Twenty-eight cases coded as extrarenal rhabdoid tumor (ERRT), RT, possible ERRT, and "large cell sarcoma" were retrieved from the Armed Forces Institute of Pathology soft tissue registry. The tumors were reclassified according to strict criteria by light microscopy, clinical information, immunohistochemistry, and, in some cases, electron microscopy. Soft tissue rhabdoid tumor (STRT) was defined as (1) a tumor composed of noncohesive single cells, clusters, or sheets of large tumor cells with abundant glassy eosinophilic cytoplasm, an eccentric vesicular nucleus, and an extremely large nucleolus; (2) positivity for vimentin and/or cytokeratin or other epithelial markers by immunostaining; and (3) exclusion of other tumor types with rhabdoid inclusions (melanoma, other sarcomas, carcinoma). Eighteen cases met our criteria for soft tissue rhabdoid tumors. The median patient age was 13 years (range, 6 months to 56 years). Ninety-four percent of STRT cases were positive for vimentin and 59% for pan-cytokeratin. Sixty-three percent and 60% were positive for CAM 5.2 and EMA, respectively. Seventy-nine percent stained for at least one epithelial marker; 76% stained for both vimentin and epithelial markers simultaneously. Forty-two percent stained for MSA, and 14% for CEA and SMA. CD99, synaptophysin, CD57 (Leu-7), NSE, and focal S100 protein were identified in 75%, 66%, 56%, 54%, and 31% of the STRT cases, respectively. All STRT cases examined were negative for HMB-45, chromogranin, BER-EP4, desmin, myoglobin, CD34, and GFAP. Follow-up examination in 61% of the STRT patients revealed that 64% of patients died of disease within a median follow-up interval of 19 months (range, 4 months to 5 years); 82% had metastases to lung, lymph nodes, or liver; 22% had local recurrences before metastasis; and 18% were alive without known disease status (median, 5.5 years). Soft tissue rhabdoid tumor is a highly aggressive sarcoma, predominantly of childhood. Besides having nearly consistent coexpression of vimentin and epithelial markers, STRTs show positivity for multiple neural/neuroectodermal markers that overlap with those of primitive neuroectodermal tumor.
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PMID:Extrarenal rhabdoid tumors of soft tissue: a clinicopathologic and immunohistochemical study of 18 cases. 993 May 72

From a series of 100 consecutive breast carcinomas with axillary lymph node metastases, two cases of necrotic granulomas in the nodes are presented. Lymph nodes in each case were characterized by areas of necrosis surrounded by a palisade of cells resembling histiocytes as seen in a rheumatoid nodule. Although the initial impression was that of a reactive granuloma, when immunostained for keratin and EMA, the areas of necrosis showed positive staining for keratin and EMA in a cytoplasmic pattern. The surrounding palisade of cells stained with histiocyte markers, while the necrotic area itself was negative. Staining for both estrogen and progesterone markers was also negative. Staining of nine lymph nodes with caseating granulomas not associated with carcinoma with the same panel of antibodies revealed no staining except for irregular, noncellular staining with EMA. This pattern of necrosis in axillary lymph nodes from two cases of breast carcinoma was interpreted as evidence of necrotic metastatic tumor cells. Necrosis in axillary lymph nodes associated with invasive breast cancer should arouse suspicion for metastasis.
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PMID:Breast carcinoma associated with necrotic granulomas in axillary lymph nodes. 993 May 74

Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.
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PMID:High-grade carcinoma component in epithelial-myoepithelial carcinoma of salivary glands clinicopathological, immunohistochemical and flow-cytometric study of three cases. 1033 39

Salivary duct carcinoma (SDC) is a high-grade neoplasm known to histologically resemble high-grade ductal carcinoma in situ of the breast. We describe 3 cases of sarcomatoid salivary duct carcinoma, a heretofore unreported variant of SDC. Each case was a composite of SDC and sarcomatoid carcinoma and histologically similar to reported cases arising in the breast. The clinicopathologic features, including immunohistochemistry, of 3 cases were investigated. In the 3 men, ages 56, 68, and 70 years, the resected parotid tumors measured 1.5, 3.5, and 1.5 cm, respectively. Only the 3.5-cm tumor extended beyond the parotid gland into soft tissue. This patient died at 3 years with pulmonary metastases. The other patients were free of disease at 6 and 12 months. Histologically, each case was a composite of usual-type SDC and sarcomatoid carcinoma. SDC showed typical cribriform architecture, whereas anaplastic, spindled cells constituted the sarcomatoid areas. Immunohistochemically, epithelial elements stained as follows: cytokeratin (AE1/AE3 & CAM 5.2) positive in 3 of 3 cases, EMA positive in 3 of 3 cases, vimentin negative in 3 of 3 cases, desmin negative in 3 of 3 cases, c-erbB-2 positive in 1 of 2 cases. Sarcomatoid elements stained as follows: AE1/AE3 negative in 3 of 3 cases, CAM 5.2 rare positive cell in 1 of 3 cases, EMA focally positive in 3 of 3 cases, vimentin positive in 3 of 3 cases, desmin negative in 3 of 3 cases, c-erbB-2 negative in 2 of 2 cases. Electron microscopy, performed in one case, showed scattered junctional complexes congruent with epithelial differentiation. Immunohistochemical results, EMA and CAM 5.2 positivity, and ultrastructural findings supported our belief that these unique biphasic tumors represented SDC with sarcomatoid carcinoma. We conclude an element of sarcomatoid carcinoma rarely may arise in association with SDC, and it is erroneous to diagnose such tumors as "carcinosarcoma."
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PMID:Sarcomatoid salivary duct carcinoma of the parotid gland. 1068 35

The separation of benign from malignant mesothelial proliferations has emerged as a major problem in the pathology of the serosal membranes. For both epithelial and spindle cell mesothelial processes, true stromal invasion is the most accurate indicator of malignancy, but stromal invasion is often difficult to assess, especially in small biopsies. In the pleural cavity, deep penetration of a thickened and fibrotic pleura or penetration of mesothelial cells into the fat of the chest wall are good indicators of malignancy; however, superficial entrapment of mesothelial cells and glands by organizing effusions is common in benign reactions and needs to be distinguished from invasion. In the peritoneal cavity, invasion of fat or of organ walls is again the most reliable indicator of malignancy, but entrapment of benign cells in organizing granulation tissue or between fat lobules is frequent and confusing. Proliferations confined to the pleural or peritoneal space, particularly linear arrays of atypical mesothelial cells on the free surface, should not be called malignant in the absence of unequivocal invasion. Cytologic atypia is often not helpful in separating benign from malignant reactions, because benign processes are commonly atypical and mesotheliomas are often deceptively monotonous. Densely packed mesothelial cells within the pleural space are frequent in benign reactions, but densely packed mesothelial cells within the stroma favor a diagnosis of malignancy. Organizing effusions (fibrous pleurisy) typically show zonation with high cellularity and cytologic atypia toward the pleural space and increasing fibrosis with decreasing cellularity and lesser atypia toward the chest wall, whereas sarcomatous (including desmoplastic) mesotheliomas do not demonstrate this type of zonation. Elongated capillaries perpendicular to the pleural surface are seen in organizing effusions but are not a feature of sarcomatous mesotheliomas. The combination of a paucicellular storiform pattern, plus invasion of the stroma (including fat and adjacent tissues), or bland necrosis, overtly sarcomatous foci, or distant metastases, is required for the diagnosis of desmoplastic mesothelioma. Necrosis is usually a sign of malignancy but is occasionally seen in benign mesothelial reactions. Keratin staining is useful in indicating the distribution of mesothelial cells, and particularly in demonstrating penetration of mesothelial cells into the stroma or adjacent structures, but is of no help in separating benign and malignant proliferations because both are keratin-positive. Although both p53 and EMA staining have been proposed as markers of mesothelial malignancy, in our experience they are not helpful for the individual case.
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PMID:The separation of benign and malignant mesothelial proliferations. 1125 37

The clinicopathologic characteristics of 69 cases of eccrine porocarcinoma (EP) have been studied. Seven cases of purely in situ disease are included. Forty patients were female, 29 male with ages ranging from 29 to 91 years (mean 73 years). The lower extremity represented the single most common site (44%). Other common sites were the trunk (15 cases, 24%) and head (11 cases, 18%). The histologic diagnosis of EP was predicated on the basis of an irregular tumor at least partly formed of characteristic poromatous basaloid epithelial cells displaying ductal differentiation, and significant cytologic atypia. Forty-seven tumors (68%) contained mature well-formed eccrine ducts having an eosinophilic luminal cuticle, with the remaining tumors containing small ill-formed ducts and/or intracytoplasmic lumina. All ducts were discernible via light microscopy and in 49 cases were highlighted with DPAS stain and/or CEA/EMA immunocytochemistry. A variant with a broad pushing tumor margin and marked nuclear pleomorphism showed some resemblance to proliferative bowenoid dysplasia. In 11 cases (18%) the tumors appeared to arise in continuity with a benign preexistent poroma. A variety of histologic patterns were displayed including clear, squamous, and spindle cell differentiation, mucus cell metaplasia, and colonization by melanocytes. Lymphovascular invasion was present in 9 cases (15%). Three cases showed pagetoid extension of malignant cells (epidermotropism) and appeared to be multifocal. Follow-up was available in 54 patients (78%) with 9 (17%) experiencing local recurrence, 10 developing lymph node metastases (19%), and 6 (11%) experiencing distant metastases or death. Mitoses, the presence of lymphovascular invasion, and tumor depth >7 mm were associated with a poorer prognosis. Dividing tumors into those with a "pushing" or "infiltrating" advancing margin was also predictive of outcome with the latter having an increased risk of local recurrence. This report, the largest series of EP to date, suggests that the incidence of aggressive behavior is less than popularly believed. Furthermore, EP can display a wide variety of histologic patterns that may lead to diagnostic error in the unwary. The large number of cases in this series enables a reliable evaluation of prognostic parameters. A more aggressive clinical course may be indicated by more than 14 mitoses per high power field (hazard ratio [HR] for death 17.0, 95% confidence interval [CI] 2.71-107), lymphovascular invasion by tumor (HR 4.41, CI 1.13-17.2), and depth >7 mm (HR 5.49, CI 1.0-30.3). Thus, mitoses, lymphovascular invasion, and tumor depth should be evaluated in these tumors. We also suggest that tumors presenting an "infiltrative" advancing margin are particularly prone to local recurrence and require wide excision with close attention to the surgical margins by the reporting pathologist.
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PMID:Eccrine porocarcinoma (malignant eccrine poroma): a clinicopathologic study of 69 cases. 1181 53

Placental site trophoblastic tumor (PSTT) is a rare form of gestational trophoblastic disease (GTD), with only 100 cases reported in the literature. Irregular vaginal bleeding has been reported to be the most common presenting symptom, however, spontaneous uterine perforation, mimicking ectopic pregnancy, as the initial presentation is extremely rare, and has not yet been reported in the Chinese literature. Herein, we report a 26-year-old female with PSTT complicating with uterine perforation that mimicked ectopic pregnancy as the initial presentation. She received wide excision of the uterine perforation margin only and now remains disease-free, 2 years after the operation. Reviewing the literature, while most cases of PSTT behave a benign fashion, some exhibit malignant behavior; surgery remains the mainstay of therapy. For patients whose disease is limited to the uterus, simple total abdominal hysterectomy is the treatment of choice. For patients with extensive or metastatic disease, cytoreductive surgery (total abdominal hysterectomy and resection of extrauterine tumor load) combined with chemotherapy should be applied. Etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine (EMA/CO) chemotherapy appears superior to other available chemotherapeutic regimens in the treatment
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PMID:Spontaneous uterine perforation mimicking ectopic pregnancy as the initial presentation of placental site trophoblastic tumor. 1176 87


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