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Immunohistochemically Positive (immunohistochemically + positive)
Selected AbstractsCytologic feature by squash preparation of pineal parenchyma tumor of intermediate differentiationDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2008Keiji Shimada M.D., Ph.D. Abstract Pineal parenchyma tumor of intermediate differentiation (PPTID) is a very rare intracranial tumor, and pathological investigation limited to immunohistological and ultrastructural analyses have been published to date. Although intraoperative cytology is one of the important approaches for initial diagnosis in brain tumors, no or little studies on cellular morphology of PPTID have been demonstrated due to its rarity. We report here cytological features of PPTID obtained from stereotactic surgical specimens in a case of 27-year-old female manifested by dizziness and diplopia. Brain MRI revealed an unhomogeneously enhanced, large-sized tumor (56 × 52 × 60 mm) mainly located in the pineal region expanding from the midbrain to superior portion of the cerebellum and the fourth ventricle. Squash cytology showed increased nucleocytoplasmic ratio, hyperchromatic nuclei, and small rosette-like cell cluster but cellular pleomorphism was mild to moderate and necrotic background was not observed. Histology showed high cellularity, moderate nuclear atypia, and small rosette formation but neither bizarre tumor cells nor necrosis was present. Mitotic counts were very low (less than 1 per 10 high-power fields) and the MIB-1 labeling index was relatively high (10.1%). Tumor cells were immunohistochemically positive for neural markers such as synaptophysin, neurospecific enolase but not for glial fibrillary acidic protein or S-100. In some parts, cells were strongly reactive for neurofilament protein. Taken together, we made a final diagnosis of PPTID. This is the first presentation of cytological analysis by squash preparation that gives an important clue to accurate diagnosis of pineal parenchymal tumor and to understand its malignant potential. Diagn. Cytopathol. 2008;36:749,753. © 2008 Wiley-Liss, Inc. [source] Congenital myofibroma of the skin mimicking a piloleiomyomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2010Takuya Inoue Myofibroma is an uncommon benign soft tissue disorder, which is usually congenital or present in early infancy. Myofibroma usually manifests as a single mass. When there are multiple lesions, the term myofibromatosis is used. The characteristic histopathological feature of the myofibroma is the coexistence of two distinct areas. One area mainly contains plump spindle cells with thin blunt-ended nuclei and eosinophilic cytoplasm, thus indicating myoid characteristics. The other area contains either round or polygonal cells with slightly pleomorphic, hyperchromatic nuclei or small spindle cells typically arranged around a distinct hemangiopericytoma-like vascular pattern. In the present case, the majority of the tumor was composed of the plump myoid spindle cells. This led to an initial diagnosis of a piloleiomyoma. However, the tumor cells were not immunohistochemically positive for desmin. Moreover, careful examination revealed a hemangiopericytoma-like vascular pattern characterized by the presence of high cellular areas with irregular vascular spaces. These features led to the final diagnosis of the myofibroma. It is therefore important to recognize the leiomyoma-like variants of myofibromas. Inoue T, Sada A, Mori T, Misago N, Narisawa Y. Congenital myofibroma of the skin mimicking a piloleiomyoma. [source] Multiple endocrine neoplasia type 1-associated cystic pancreatic endocrine neoplasia and multifocal cholesterol granulomasPATHOLOGY INTERNATIONAL, Issue 4 2010Noriko Kimura A novel combination of tumors was found in a 68 year-old female with Multiple Endocrine Neoplasia type-1 (MEN 1) that included a cystic pancreatic endocrine neoplasm (CPEN), a pituitary adenoma, and multifocal cholesterol granulomas (MCGs) in the breast, pleura, and the extremities. The pancreatic tumor displayed a single central locule surrounded by a thin rim of neoplastic parenchyma. The tumor showed heterogeneity in the architecture that included glandular, trabecular and solid patterns. The tumor cells of the pancreas were immunohistochemically positive for both endocrine and pancreatic acinar markers including chromogranin A, synaptophysin, glucagon, lipase, and reg protein. Electron microscopy revealed that there were numerous smaller dense-cored neurosecretory granules, larger zymogen-like granules and microvilli on the apical side of the tumor cells. The pancreatic tumor was diagnosed as CPEN with acinar cell features. Analysis of the DNA extracted from the tissues revealed that there is a MEN1 germline mutation in exon 10 codon 527, and somatic mutation in exon 2 codon 32 in the pancreatic tumor, and one base pair deletion in exon 2 codon 79 in the pituitary adenoma. Here, we report the case and discuss possible pathogenesis of CPEN and MCGs in a patient with MEN 1. [source] Cytokeratin 20-positive large cell neuroendocrine carcinoma of the colonPATHOLOGY INTERNATIONAL, Issue 8 2005Tomoya Kato Herein is presented a case of cytokeratin (CK) 20-positive large cell neuroendocrine carcinoma of the colon, in which the tumor was clinically at stage IV and located in the ascending colon. Pathological examination of the resected tumor revealed nested and solid proliferation of large undifferentiated cells with vesicular nucleus and prominent nucleoli. No areas showed differentiation toward adenocarcinoma or squamous cell carcinoma. Tumor cells were immunohistochemically positive for chromogranin A, synaptophysin, CD 56 (focal), and bore electron-dense granules. With these features, the tumor was diagnosed as a large cell neuroendocrine carcinoma of the colon. Liver metastasis and local recurrence progressed, and the patient died of the primary disease 7 months after operation. The autopsy confirmed this diagnosis without detectable tumors in the lungs. Interestingly, more than half of the tumor cells were positive for CK 20, while CK 7 was not expressed. Most neuroendocrine carcinomas do not express CK 20, with the exception of Merkel cell carcinomas, and most colorectal adenocarcinomas express CK 20. To the best of the authors' knowledge, the present case is the first CK 20-positive, CK 7-negative colorectal neuroendocrine carcinoma to be described, suggesting a link between colorectal neuroendocrine carcinoma and conventional adenocarcinoma. [source] PKC theta, a novel immunohistochemical marker for gastrointestinal stromal tumors (GIST), especially useful for identifying KIT-negative tumorsPATHOLOGY INTERNATIONAL, Issue 3 2005Atsushi Motegi Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the digestive tract and the majority of GIST has characteristic gain-of-function mutations of the c-kit gene, which encodes the KIT receptor for stem cell factor. The present study aimed to establish the usefulness of protein kinase C theta (PKC ,) as an immunohistochemical marker for GIST in comparison with KIT immunohistochemistry. PKC , immunohistochemistry was carried out not only on 48 cases of GIST and another 40 cases of gastrointestinal mesenchymal tumors, but also on 24 cases of various tumors known to be immunohistochemically positive for KIT. Immunohistochemically, 41 out of 48 cases (85%) of GIST were positive for PKC ,, and its expression was confirmed by Western blot analysis using six cases of surgically resected GIST. In the present study there were six GIST immunohistochemically negative for KIT, which histologically revealed a myxoid epithelioid appearance characteristic to that of GIST with platelet-derived growth factor receptor alpha mutation. All six GIST were immunohistochemically positive for PKC ,. No PKC , immunoreactivity was observed in other gastrointestinal mesenchymal tumors and various KIT-positive tumors except for three cases (14%) of gastrointestinal schwannomas. The present study revealed that PKC , is an immunohistochemically novel and useful marker for GIST, especially for GIST negative for KIT. [source] Histopathological characterization of aortic intimal sarcoma with multiple tumor emboliPATHOLOGY INTERNATIONAL, Issue 11 2000Naoki Nishida A case of aortic intimal sarcoma with multiple tumor emboli and distal metastasis is reported. All metastasis (adrenal, spleen) were via the arteries. This case also had independent lung cancer. Macroscopically, the aortic tumor did not form a bulged mass, but had linear ulceration with abundant mural thrombi. Poorly cohesive large atypical cells were seen in the intima of the abdominal aorta without invasion into the media. Tumor cells were disseminated into the mural thrombi on the aorta and embolized its branches. In the metastatic tumor or tumor emboli of the distal artery, there were not only large atypical cells, but also the foci of spindle-shaped cells or epithelioid differentiation. Tumor cells in the aorta were immunohistochemically positive for only vimentin. Muscle-specific actin was positive focally for spindle-shaped cells of tumor emboli and metastatic tumors. Furthermore, cytokeratin-positive cells were scatteredly seen. All tumor cells were negative for factor VIII and did not have a histologic or phenotypic analogy with lung cancer. The primary intimal sarcoma in the present case was of undifferentiated non-endothelial intimal stromal cell origin, and may have had multipotential for differentiation. Investigation of the metastatic site was useful for recognizing the features of this tumor. [source] Adenomyosis with a sex cord-like stromal elementPATHOLOGY INTERNATIONAL, Issue 4 2000Masaharu Fukunaga A case of adenomyosis with a sex cord-like stromal element is described. The element was an incidental, solitary, microscopic finding in a focus of adenomyosis. It was characterized by cord and trabecular arrangements of round to polygonal shaped cells in the endometrioid stroma. The cells were immunohistochemically positive for desmin and alpha-smooth muscle actin but negative for sex cord markers (alpha-inhibin and O13). The element appears to originate from the endometrial stromal cells through smooth muscle metaplasia. [source] Aggressive digital papillary adenocarcinoma on the palm with pulmonary metastasesTHE JOURNAL OF DERMATOLOGY, Issue 7 2008Junko NISHIMOTO ABSTRACT A 41-year-old Japanese male had aggressive digital papillary adenocarcinoma with pulmonary metastases. He had an asymptomatic, solitary, dome-shaped, skin-colored firm nodule on his left palm for half year. The tumor consisted of multiple lobules of anaplastic epithelial cells with central necrosis. The neoplastic cells were immunohistochemically positive for cytokeratin and S-100 protein. Two years after the lesion was removed, pulmonary nodular lesions were found on chest X-ray. On histopathological examination, the pulmonary biopsy specimens showed lobular proliferation of acantholytic tumor cells and some ductal structures associated with papillary projections. Five years after the initial removal of the lesion, the patient was referred to our hospital because of a recurrent skin nodule on his left palm. The recurrent skin tumor was found to have lobular proliferation of anaplastic cells. On immunohistochemistry, the pulmonary metastasis and the palmar skin nodules were identical. The tumor was diagnosed as an aggressive digital papillary adenocarcinoma. This report is a rare case of aggressive digital papillary adenocarcinoma that was diagnosed based on the histopathology of the pulmonary metastases, which showed ductal structures associated with papillary projections. [source] Granular cell tumor arising metachronously in the bronchus and esophagus,APMIS, Issue 9 2006Case report We present a case of granular cell tumor (GCT) occurring in the esophagus 7 years after operation for bronchial GCT. A 59-year-old Japanese man complained of epigastralgia, and endoscopic examination of the upper digestive tract disclosed a submucosal tumor in the lower esophagus. Histological examination of the endoscopic mucosal resection of the esophageal tumor showed a proliferation of neoplastic cells with an eosinophilic and granular cytoplasm. The cytoplasm of the neoplastic cells was histochemically positive for PAS stain and immunohistochemically positive for S-100. This tumor did not fulfill any of the diagnostic criteria for malignancy at either the macroscopic or microscopic level. I believe that this is the first case of GCT occurring metachronously in the respiratory and digestive tracts. Clinicians and pathologists should bear in mind that GCT may arise metachronously in the respiratory and digestive tracts. [source] | ||||||||||||||||||||||