Cytokeratin 7 and 20 as immunohistochemical markers in identification of primary tumors in craniospinal metastases: Do they have a significant role?

Cytokeratin (CK)7 and CK20, the low molecular weight cytokeratins, have been found to have a benefit in the differential diagnosis of some epithelial neoplasms. In the present study, the actual role of these markers in the search of primary tumors in 32 patients with craniospinal metastasis of an unknown primary site at presentation, is evaluated. A series of 36 patients with a known primary tumor were presented for comparison. In the first group, two CK7 and CK20 expression profiles were observed; 87% of metastatic tumors were CK7+/CK20‐ and 13% CK7‐/CK20‐. The lung was the major source (82%) of CK7+/CK20‐ metastatic tumors, whereas it represented only 38% of primary tumor in the second group of a known primary site (P = 0.006). Given the fact that metastatic tumors to the craniospinal axis of an unknown primary site are frequently CK7+/CK20‐, and they have commonly metastasized from the lung, it is doubtful that immunohistochemistry is really helpful. However, CT scan and MRI of the chest still play an important role. Many patients in the present study had to undertake these imaging studies, regardless of the CK7/CK20 result. The immunostains may be useful in cases with other expression profiles, but such examples constituted only a minority in the present study.     

Symptomatic neuroepithelial cysts in the posterior cranial fossa. Immunohistochemical and electron-microscopic studies

A 2-year-old boy had increased intracranial pressure and convulsions because of two extraventricular cysts in the posterior cranial fossa. Releasing the watery cyst contents resulted in disappearance of such clinical manifestations. Immunohistochemically, the epithelial cytoplasm of the cyst was strongly positive for glial fibrillary acidic protein. Electron-microscopically, the cells that lined the cysts had microvilli which were coated with finely granular material to represent "fuzzy" coat, intercellular junctions linking the plasma membranes of adjacent cells, and numerous cytoplasmic glial filaments. The strong positivity for glial fibrillary acidic protein, then, is well correlated with an abundance of the latter. Cilia were also identified. Thus, the cysts were unequivocally neuroepithelial (ependymal) cysts. Only nine cases of neuroepithelial cysts in the posterior cranial fossa, including the current one, have been reported. Three patients were children; six were adults. The age of the patients ranged from 7 months to 60 years. The average age was 21.7 years The sex was known in eight patients with a male to female ratio of 3:5. The pathogenesis of these neuroepithelial cysts was proposed as related to developmental anomalies.     

Ganglioglioma of the optic chiasm: case report and review of the literature

We report a case of a hypothalamic chiasmatic ganglioglioma in a 21-year-old woman who presented with hyperprolactinemia and developed visual field defects. This circumscribed cystic lesion with an enhancing mural nodule was radiologically indistinguishable from a pilocytic astrocytoma. Although rare, gangliogliomas should be included in the differential diagnosis of lesions occurring in this area of the brain.     

Supratentorial extraventricular ependymal neoplasms: a clinicopathologic study of 32 patients

BACKGROUND: Published research on the clinicopathologic features of extraventricular ependymal neoplasms of the cerebral hemispheres has been scant. METHODS: Thirty-two archival cases were studied to investigate the prognostic impact of clinicopathologic parameters including flow cytometry, the proliferation (Ki-67) labeling index, and p53 expression. RESULTS: Among these 32 cases were 2 subependymomas, 19 ependymomas, and 11 anaplastic ependymomas. No significant gender predilection was observed, and 45% of patients were in their second or third decade of life. The left cerebral hemisphere was 1.5 times more commonly involved. On available imaging studies, lesions were often cystic, with or without a mural nodule. Tumors expressed glial fibrillary acidic protein (87%), S-100 protein (77%), cytokeratin (43%), and epithelial membrane antigen (17%). Ki-67 proliferation index paralleled tumor grade. Immunoreactivity for p53 protein was observed in the 2 cases of subependymoma, in 10 of 11 anaplastic ependymomas, and in 6 of 17 ependymomas. Flow cytometry performed in 27 tumors revealed diploidy in 20 cases and aneuploidy in 4 cases (3 anaplastic and 1 classic ependymomas), with S-phase fraction ranging from 0.2-9.7. Eleven subjects were additionally treated with radiotherapy, and 3 with chemotherapy. Follow up was available in 25 (78%) patients. CONCLUSIONS: The results of the current study suggest that there is no significant relation between histopathology, Ki-67 proliferation index, p53 immunolabeling, tumor ploidy, and biologic behavior.     

Malignant mesenchymoma of ulnar nerve: combined sarcoma of nerve sheath and rhabdomyosarcoma.

Malignant mesenchymoma within the right ulnar nerve of an 8 year old boy is described. The patient did not have stigmata of von Recklinghausen's neurofibromatosis. The growing and painful tumour was excised five and a half detection, and recurred five months later. Mingling of the nerve sheath sarcoma and rhabdomyosarcoma was noted within the same mass which was separated from the adjacent striated muscles. It is suggested that this mesenchymoma arose from mesenchymal cells or cells of mesenchymal type comprising the peripheral nerve sheath which is derived from ectomesenchyme of the neural crest.