Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report the case of a 77-year-old woman in whom choroidal metastasis was the initial manifestation of a primary neoplasm presumed to be a pigmented pulmonary carcinoid tumor. The tumor initially was misdiagnosed cytologically and pathologically as a choroidal melanoma because it contained intrinsic melanin pigment. Positive immunoreactivity for cytokeratin, synaptophysin, chromogranin, and calcitonin and the presence of dense-core neurosecretory vesicles disclosed by electron microscopy established that the metastasis was a neuroendocrine tumor. Findings from systemic evaluation suggested that the primary tumor was located in the lung. The patient subsequently developed an intradural paraspinal metastasis, which also contained melanin pigment. The latter observation confirmed that the melanin in the uveal metastasis was intrinsic and did not represent secondary phagocytosis by tumor cells. Metastases from pigmented tumors of nonmelanocytic derivation are exceedingly rare but present a major diagnostic challenge to ocular pathologists and cytopathologists if the diagnosis is not suspected. Confirmatory immunohistochemical analysis should be obtained when a pigmented choroidal tumor thought to be a melanoma has atypical features. Arch Ophthalmol. 2000;118:841-845
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PMID:Choroidal metastasis as the initial manifestation of a pigmented neuroendocrine tumor. 1086 24

We report an aggressively behaving malignant trichogenic tumor arising in a trichoblastoma (TB) with widespread lymphatic and hematogenous metastases in a 55-year-old man with a concomitant B-cell chronic lymphocytic leukemia. The primary tumor had been present and unchanged for as long as 40 years before excision. Typical trichogenic TB with dystrophic calcification and even ossification was still present peripheral to the malignant transformation. The malignant neoplasm consisted of basaloid cells, spindle cells arranged in fascicles and densely packed rounded nests or "cell balls." The metastases consisted of immature basaloid cells and cell balls, and the recurrences became successively more undifferentiated. The residual TB reacted with antibodies to cytokeratin (CK) 6, 8, 14, and 17 and focally to S-100; the malignant primary tumor reacted uniformly with antibodies to vimentin and only focally with antibodies to CK and S-100. The metastatic tumor had lost epidermal CK expression but maintained expression of S-100 in paraffin-embedded tissues. Trichoblastic differentiation was confirmed in frozen tissues with antibodies to hair keratins. No expression of p53 or bcl-2 was identified, but p-glycoprotein (MDR-1 gene related) was expressed by primary and metastatic tumor cells. We believe that this neoplasm is best classified as a trichoblastic carcinoma arising in a TB in association with a B-cell chronic lymphocytic leukemia. This case illustrates that TBs have the potential for malignant transformation and aggressive behavior.
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PMID:Trichoblastic carcinoma ("malignant trichoblastoma") with lymphatic and hematogenous metastases. 1087 73

An elevation of melatonin secretion parallel to an enhanced production of macrophage-derived biopterin was observed in female F344 Fischer rats bearing passage 2 serial transplants derived from a malignant mammary tumor induced by 7,12-dimethylbenz[a]anthracene (DMBA). As opposed to that both parameters were depressed at passage 12. These results indicate the presence of divergent immunoneuroendocrine interactions during different phases of tumor growth. Since these biochemical events must have their common origin in changes taking place within these tumor transplants the current histopathological study was initiated. The primary tumor used for serial transplantation was a moderately differentiated adenocarcinoma of the mammary gland showing cytokeratin-positive epithelial components located in the inner epithelial tubule layer. In addition, bland-looking round or elongated actin-positive myoepithelial cells were detected which apart from epithelial cells are known to constitute the main cellular components of the mammary ductal system which resemble smooth muscle cells both morphologically and functionally. The tumor of passage 1 showed glandular tubules, lined by an inner epithelial layer, and many nests of clear, bland-looking actin-positive myoepithelial cells lying around tubules as well as in the stroma between actin-negative epithelial elements. The tumor of passage 2 used for transplantation consisted of a chaotic mixture of epithelial carcinomatous cells, forming a few irregular small tubules or solid nests, and, predominantly, of elongated plump or spindle-shaped, "myoid" atypical myoepithelial cells with a strong actin-positive reaction and some of these cells showed a focal vimentin expression. The tumor was characterized as a carcinosarcoma. At passage 12 epithelial cells were not identified. The tumor displayed features of a pleomorphic sarcoma consisting mainly of giant cells with bizarre nuclei being cytokeratin- and desmin-negative, weakly vimentin-positive but strongly actin-positive. These results indicate that DMBA-induced mammary tumor cells in female F344 Fischer rats undergo dramatic morphological changes during serial transplantation characterized by a total loss of malignant epithelial (carcinomatous) cells and the emergence and subsequent predominance of malignant (sarcomatous) mesenchymal cells. It appears that these sarcomatous cells develop out of myoepithelial cells since atypical myoepithelial cells with a strong actin-positive reaction showed a focal vimentin expression at passage 2 indicating myofibroblastic differentiation as part of mesenchymal transition. The loss of epithelial cell elements as well as a parallel transition of myoepithelial to mesenchymal cell elements during passaging could lead to a lack of immunological recognition of these tumor transplants and to depression of melatonin. Possible mechanisms involved in these phenomena as well as the relevance of these findings for a better understanding of the role of melatonin in human mammary cancer are discussed.
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PMID:Serial transplants of DMBA-induced mammary tumors in fischer rats as model system for human breast cancer: V. Myoepithelial-mesenchymal conversion during passaging as possible cause for modulation of pineal-tumor interaction. 1096 82

One objection to using cell cultures for studying the proliferation of tumors is the potential for phenotypic changes that may occur in vitro. Here, we compared the antigen pattern expression of cultured meningioma cells with that of the primary tumor. Cell cultures established from 9 intracranial meningiomas and deparaffinized sections of the resected tumors were analyzed for immunophenotyping with the following antibodies: vimentin, cytokeratin, epithelial membrane antigen, S-100, neuron-specific enolase, synaptophisin, factor VIII-related antigen, CD4, CD31, CD34, CD45RB, CD68-PGM1, CD68-KP, and myeloid/histiocyte antigen (MAC387). Overall, the cultured meningioma cells retained the main feature of the primary tumor, being positive both for mesenchymal antigens and for epithelial antigens. Interestingly, the cultured meningioma cells abundantly expressed the CD68 antigens at early passage. The CD68 antigens, which are normally found on hematopoietic cells like macrophages and monocytes, were not detectable on meningioma cells in situ. Our results show that phenotypic changes on human meningioma cells may occur in vitro. This phenomenon suggests caution when transposing the in vitro results to the in vivo condition.
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PMID:Phenotypic change of human cultured meningioma cells. 1113 90

Cardiac myxoma is the most common primary tumor of the heart. Between 1970 and 1998, 33 myxomas from patients operated at the Cardiosurgical Department were submitted for pathological examination. A review of age, sex and clinical symptoms of the patients as well as of gross and histological features of the tumors is presented. Immunohistochemical examination was performed on 10 selected myxomas-reactivity to vimentin, desmin, S-100 protein, cytokeratin and FVIIIR-Ag. The necessity of histological examination of the embolectomy material is stressed.
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PMID:[Cardiac myxomas]. 1118 10

Numerous studies have shown tumor cells in bone marrow to be a new and independent prognostic factor in primary breast cancer. The presence of such cytokeratin-positive or mucin-positive cells reflects the biology and systemic character of breast cancer much better than lymph node status. Axillary lymphadenectomy is associated with a considerable number of complications and is completely unnecessary in about 50% of cases (in node-negative patients). Whether axillary node dissection contributes to improved survival is highly controversial. However, since nearly all patients with primary breast cancer now receive adjuvant systemic therapy, the value of the classic prognostic factors must be discussed and re-evaluated. Much information can now be determined from primary tumor (HER-2/neu, etc). Tumor cell detection in bone marrow is a simple method that can be performed on an outpatient basis and that can be repeated if necessary (for monitoring therapy). The main disadvantage of the technique is that it has not been possible to standardize the laboratory methods and to find the ideal antibody--one that is not only able to recognize an epithelial cell, but which can also describe its metastatic potential. Semin Oncol 28:236-244.
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PMID:Bone marrow staging for breast cancer: is it better than axillary node dissection? 1140 33

A variable proportion of bile duct adenomas of the liver are still confused with metastatic well-differentiated adenocarcinoma by surgeons and pathologists. We present here three examples of previously undescribed primary hepatic bile duct tumors that were composed almost entirely of clear cells that closely mimicked metastatic renal cell carcinoma. They were interpreted as atypical bile duct adenomas and occurred in two males and one female whose ages ranged from 25 to 64 years. All three tumors were incidental findings and measured from 0.8 to 1.1 cm. The clear neoplastic cells showed mild nuclear atypia and no mitotic activity. They were arranged in tubules and nests that focally infiltrated the hepatic parenchyma. For comparison, a case of clear cell cholangiocarcinoma and 13 conventional bile duct adenomas were examined. The clear cell cholangiocarcinoma was larger (6.0 cm) and had the tubular pattern of conventional cholangiocarcinoma and an abundant desmoplastic stroma. The clear cells of this tumor exhibited greater nuclear atypia and increased mitotic activity. All three atypical bile duct adenomas expressed cytokeratin (CK) 7, p53 protein, epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA); they were negative for CK20, vimentin, Hep Par 1, chromogranin, and prostatic specific antigen (PSA) and exhibited less than 10% of Ki-67-positive nuclei. One atypical bile duct adenoma displayed luminal immunoreactivity for villin. With the exception of Ki-67 reactivity, the 13 conventional bile duct adenomas and the clear cell cholangiocarcinoma had essentially a similar immunohistochemical profile as that of the atypical clear cell bile duct adenomas. The absence of an extrahepatic primary tumor, the histologic features, the immunohistochemical profile, and the fact that all patients are symptom-free 2 months to 18 years after wedge liver biopsy support the interpretation of atypical clear cell bile duct adenoma. The differential diagnosis with clear cell hepatocellular carcinoma and metastatic clear cell carcinomas is discussed.
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PMID:Atypical bile duct adenoma, clear cell type: a previously undescribed tumor of the liver. 1142 Apr 69

We describe an insulinoma of the pancreas in a 56-year-old patient, which showed insular-ductular differentiation in its liver metastasis. Although the primary tumor was uniformly endocrine in nature with insulin production, the metastasis contained two distinct cell types in organoid arrangement. One cell type was insulin-positive and was arranged in islet-like structures; the other was insulin-negative but distinctly pan-cytokeratin and cytokeratin 7 positive and arranged in ducts. In the primary tumor and the metastasis, the tumor cells were surrounded by a desmoplastic stroma. As to the histogenesis of the tumor and its metastasis, we discuss the following possibilities: (1) the tumor cells might derive from a common stem cell that matures into two phenotypically different cell lines, resembling the situation in embryogenesis and (2) one tumor cell type originates from the other by transdifferentiation (metaplasia). We conclude that the parallel occurrence of endocrine and ductal differentiation supports the concept that, under certain conditions, islet cells and ductular cells may also originate from islets and that mixed endocrine/exocrine pancreatic tumors do not necessarily arise from totipotent duct cells but might also have a primary endocrine cell origin.
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PMID:Insulinoma of the pancreas with insular-ductular differentiation in its liver metastasis--indication of a common stem-cell origin of the exocrine and endocrine components. 1146 96

A 43-year-old woman who had a vulvar mass associated with mild discomfort was found to have a rare primary vulvar adenocarcinoma of probable cloacal origin. The tumor was contiguous with the surface epithelium of the vulva and was a well to moderately differentiated adenocarcinoma of colonic type. Stains of the neoplastic cells were positive for both acid and neutral mucin, and periodic acid-Schiff (PAS) was positive after diastase reaction. The neoplastic cells were strongly positive for carcinoembryonic antigen, broad spectrum cytokeratin, and p-53 antigen. Clinical evaluation failed to show any primary tumor in colon, lung, or breast. The patient was disease free 18 months after operation.
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PMID:Primary vulvar adenocarcinoma of cloacogenic origin. 1153 Nov 87

Thorough pathologic examination of the sentinel lymph node (SLN) improves the accuracy of breast cancer staging and reduces the rate of false-negative results. Intraoperative examination of the SLN with cytological or frozen section techniques remains problematic. Diagnostic difficulties encountered on hematoxylin and eosin paraffin sections in general are easily resolved with cytokeratin immunohistochemistry, but the finding of minute metastases may lead to diagnostic and therapeutic dilemmas. Pathologic characteristics of the primary tumor and SLN metastasis determine the risk of non-SLN metastasis in the same lymphatic basin.
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PMID:Histopathologic assessment of the sentinel lymph node in breast cancer. 1159 1


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