1/127. Malignant transformation of an optic disk melanocytoma.PURPOSE: To report a case of malignant transformation of an optic disk melanocytoma with a second melanocytoma in the ciliary body. methods: Clinical data including visual acuity, visual fields, color fundus photographs, fluorescein angiogram, and ultrasonogram and histopathologic studies of this case were reviewed. RESULTS: The right eye of a 65-year-old white woman was diagnosed with melanocytoma of the optic nerve. Four years later, the tumor became significantly larger. The best-corrected visual acuity declined from 20/40 to counting fingers and the size of the tumor increased fourfold in 2 years. The right globe was enucleated. Histopathologic studies demonstrated moderately pigmented spindle-B malignant melanoma cells adjacent to and within a population of large, polyhedral, heavily pigmented melanocytoma cells that extended to the lamina cribrosa and optic nerve. There was also a deeply pigmented melanocytoma in the ciliary body. CONCLUSION: This is a rare case of malignant melanoma transformed from an optic disk melanocytoma. Periodic follow-up of the patient with optic disk melanocytoma is necessary.- - - - - - - - - - ranking = 1keywords = lamina (Clic here for more details about this article) |
2/127. Microcystic meningioma arising in a mixed germ cell tumor of the testis: a case report.We report a case of a microcystic variant of meningioma arising in a mixed germ cell tumor of the testis composed predominantly of mature and immature teratoma with elements of seminoma and embryonal carcinoma. We believe this is the first such case of a meningioma arising in a teratoma within a gonadal or extragonadal site. The meningiomatous component showed positive immunohistochemical staining for epithelial membrane antigen and a lack of staining for cytokeratin, factor viii, CD31, and alpha-fetoprotein. Recognition of a non-germ cell tumor arising in the setting of a teratoma in the testis may be prognostically important depending on the nature of the non-germ cell component and whether it has spread beyond the testis.- - - - - - - - - - ranking = 0.42554058730351keywords = membrane (Clic here for more details about this article) |
3/127. Demonstration of HPV 24 in long-standing Heck's disease with malignant transformation.We report on the rare case of a 64-year-old European woman with a viral acanthoma of the oral mucosa of the clinical Heck type with unprecedented molecular-biological proof of HPV 24 dna and so far undescribed malignant transformation with a long existence of the vegetation. After surgical therapy a circumscribed relapse of viral acanthoma developed, which responded favourably to a combined antiviral and antiproliferative therapy with acitretin perorally and interferon, first subcutaneously, later intralesionally for 3 months.- - - - - - - - - - ranking = 3.1624118934657keywords = mucosa (Clic here for more details about this article) |
4/127. Richter's transformation presenting as an obstructing endobronchial lesion.A 60-year-old man with chronic lymphocytic leukemia presented to our institution with a recurring lingular pneumonia. On fiberoptic bronchoscopy, the patient was found to have an endobronchial mass obstructing the lingula and left upper lobe. biopsy specimens of the mass demonstrated anaplastic large cell lymphoma consistent with Richter's transformation. Only one case of endobronchial Richter's transformation has been previously reported in the literature. This was described as peribronchial and endobronchial leukemic infiltrates within the bronchial mucosa. We report the first case of an obstructive endobronchial mass secondary to Richter's transformation. The endobronchial mass was treated with a Nd-YAG laser to maintain airway patency while the patient underwent chemotherapy, resulting in complete resolution of the mass within the airway.- - - - - - - - - - ranking = 3.1624118934657keywords = mucosa (Clic here for more details about this article) |
5/127. Low-grade malignant perineurioma of the paravertebral column, transforming into a high-grade malignancy.A demarcated 6 x 5 cm right paravertebral tumor at the level of T6 in a 39-year-old male was removed surgically. Histologically, the tumor consisted of monomorphous benign-looking, low-cellular spindle cells embedded in desmoplastic stroma. Ten years later, the tumor recurred locally with metastasis to systemic organs, including the occipital skin. Malignancy was histologically evident by the increased cellularity, cellular atypia and mitotic activity. The patient died of respiratory failure at the age of 49. Retrospectively reviewed, the primary lesion was low-grade fibrosarcoma-like spindle cell tumor, with secondary transformation into a highly malignant form. The differential diagnoses included sclerosing epithelioid fibrosarcoma, low-grade fibromyxoid sarcoma and malignant peripheral nerve sheath tumor. Immunohistochemically, the spindle cells in the primary and recurrent tumors consistently expressed epithelial membrane antigen, vimentin, type 4 collagen and laminin. The tumor cells in the present case showed a differentiation toward perineurial cells, which are normally positive for these immunohistochemical markers. Hence, the appropriate diagnostic term should be 'malignant perineurioma', a subtype of malignant peripheral nerve sheath tumor.- - - - - - - - - - ranking = 0.42554058730351keywords = membrane (Clic here for more details about this article) |
6/127. Middle ear adenoma with neuroendocrine differentiation.The lining of the middle ear cleft is normally a thin modified respiratory type mucosa. Normal mucosa of the middle ear is devoid of salivary type seromucous glands. Middle ear adenoma is a rare tumor that seems to be derived from the middle ear mucosa. This tumor has been previously described under a variety of names because of its different nature and biological behavior. We herein report a case of middle ear tumor that shows adenomatous and neuroendocrine features. A 64-year-old woman presented with a history of hearing loss, tinnitus and stuffy feeling of the right ear. The patient was treated two times for ear polyp. She finally underwent a tympanomastoidectomy and there was no evidence of recurrence 18 months after the procedure. Histopathological examination displayed cuboidal and columnar cells, arranged as glands, trabeculae and solid sheets. Neuroendocrine differentiation was revealed by immunohistochemical staining with polyclonal antibodies against neuron specific enolase and chromogranin antigens.- - - - - - - - - - ranking = 9.4872356803971keywords = mucosa (Clic here for more details about this article) |
7/127. Transformation of monocytoid B-cell lymphoma to large cell lymphoma associated with crystal-storing histiocytes.We report a case of crystal-storing histiocytosis associated with large cell lymphoma in a patient with a history of monocytoid B-cell lymphoma 10 years previously. The cervical lymph node biopsy showed a diffuse proliferation of large lymphocytes with vesicular nuclear chromatin and distinct nucleoli. These lymphocytes were associated with numerous immunoglobulin lambda light-chain crystal-storing histiocytes, which morphologically resembled rhabdomyoblasts. Occasional lymphoid cells also showed large immunoglobulin crystals. This case establishes the association of crystal-storing histiocytes with lymphomas of mucosa-associated lymphoid tissue and emphasizes the need for immunophenotyping to distinguish these unusual cases from other tumors, particularly adult rhabdomyomas.- - - - - - - - - - ranking = 3.1624118934657keywords = mucosa (Clic here for more details about this article) |
8/127. Superficial undifferentiated small cell carcinoma of the esophagus showing an interesting growing pattern in histology.We report a case of superficial undifferentiated small cell carcinoma of the esophagus. The histology of the tumor was interesting; there was squamous cell differentiation within the epithelial layer and undifferentiated small cells growing within the submucosal layer. The tumor had a negative Grimelius reaction, suggesting no differentiation into a hormone-producing carcinoma known as an apudoma (Amine Precursor Uptake and decarboxylation (APUD)). The serum levels of ACTH and calcitonin were within normal limits. As the patient was elderly and had a history of pleural tuberculosis causing poor pulmonary function, and owing to the fulminant nature of this carcinoma, he underwent blunt dissection of the esophagus by posterior mediastinal gastric pull-up. The patient recovered quickly and was able to be discharged with a good quality of life until the tumor recurred as a liver metastasis 6 months later.- - - - - - - - - - ranking = 3.1624118934657keywords = mucosa (Clic here for more details about this article) |
9/127. Evidence for the neoplastic transformation of Von-Meyenburg complexes.Von-Meyenburg complexes (VMC) are seen frequently in the liver and are largely considered to be innocuous, with only 11 cases reported in the literature of neoplastic transformation of VMCs. The authors report three cases of cholangiocarcinoma, each occurring in a background of fibrosis and nodularity that was reported initially as micronodular cirrhosis. Although the livers showed cirrhosis, the central veins were often preserved, and regenerative activity was patchy and focal. Histologic examination revealed many VMCs, and a gradual transition from VMCs to hyperplastic or adenomatous lesions and cholangiocarcinoma. The adenomatous lesions consisted of extensive replacement of the parenchyma by tumor-like nodules of ductular proliferations without obvious features of malignancy. All three patients were older than 60 years of age and had portal hypertension. Computed tomographic scans showed multiple, small renal cysts in one patient. Immunohistochemical staining showed positivity for epithelial membrane antigen, carcinoembryonic antigen, and keratins (AE1/AE3 and CAM5.2) in tumor cells, consistent with cholangiocarcinoma. The pattern of fibrosis and nodularity in these cases is not typical of either congenital hepatic fibrosis or usual cirrhosis. The authors propose that these patients represent another aspect in the spectrum of ductal plate malformations that may be modified by other factors such as alcohol, drugs, or infection. To their knowledge, neoplastic transformation of VMCs in the background of such changes has never been reported before.- - - - - - - - - - ranking = 0.42554058730351keywords = membrane (Clic here for more details about this article) |
10/127. Migration of intradural epidermoid matrix: embryologic implications.The migratory behavior of acquired cholesteatoma matrices (those arising from the tympanic membrane) has been described previously. This tissue is derived embryologically from the first branchial groove and represents the only migratory epithelium arising from the branchial groove system. If the matrix from a cerebellopontine angle (CPA) epidermoid tumor exhibits migratory behavior similar to that of acquired cholesteatomas, a first branchial groove site of origin for CPA epidermoids would be supported. Intradural CPA epidermoid cells were grown in alpha-minimum essential medium. The cultures were examined daily, and cell mass migration rates were measured. It was observed that intradural epidermoid tumor matrix harvested from the CPA exhibited migration in vitro. Its migratory properties were indistinguishable from those of acquired cholesteatomas, which are embryologically derived from the first branchial groove. These data support the theory that purely intradural epidermoids are derived from cells of the first branchial groove.- - - - - - - - - - ranking = 0.42554058730351keywords = membrane (Clic here for more details about this article) |
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