Expression of cytokeratins in gliomas.

Metastatic carcinoma, which is a common malignant tumor seen in the central nervous system is often difficult to distinguish from glioblastoma multiforme. In general, neoplastic cells maintain fidelity in the expression of parent cell intermediate filament and immunohistochemistry remains the mainstay in diagnosis. A panel consisting of GFAP (usually positive for astrocytic tumors) and cytokeratin (usually positive for metastatic carcinomas) is most commonly used for this purpose. However, co-expression of two or more classes of intermediate filament proteins by neoplasms is a widespread phenomenon and there are reports of glial neoplasms expressing keratin markers. Our aims and objectives were to analyse the expression of both cytokeratin and GFAP in different glial tumors and metastatic carcinomas. Cases were collected for a period of two years. All the cases were diagnosed as primary or metastatic intracranial tumors. Formalin-fixed paraffin-embedded thin sections were taken on egg-albumin coated slides and immunostaining with GFAP and polyclonal cytokeratin was done. Forty-five tumors were analysed, including 35 glial neoplasms and 10 metastatic carcinomas of which 7 of the 32 astrocytic neoplasms (22%) showed focal immunoreactivity with pancytokeratin. All of the glial tumors but none of the metastatic carcinomas were positive with GFAP. So our conclusion was that co-expression of GFAP and CK is a fairly common phenomenon, especially in case of undifferentiated and high grade gliomas and this must be kept in mind while differentiating these cases from metastatic carcinoma, as CK positivity does not rule out the diagnosis of a glial neoplasm. Further studies with an expanded panel of CK is most useful for this.

Infantile hemangioendothelioma of liver: report of two cases.

Infantile hemangioendothelioma, the commonest mesenchymal tumour of liver in infancy, though benign in nature, may behave aggressively. Here reports of two such cases are presented. Both were girls and less than 1-year old. Grossly, they presented with nodular hepatic masses with features of heart failure. Histopathology of both liver masses showed intercommunicating bloodvessels, lined by single layer of plump endothelial cells showing CD-34 positivity by immunohistochemistry. Entrapped biliary channels within tumour mass showed cytokeratin positivity.

A study of morphometric and histopathological features of muscle biopsies from patients of myopathy.

The aim of this study is to analyse the morphological pattern of different types of myopathies including morphometric data. The cases were diagnosed as myopathy on the basis of clinical details, EMG findings, serum CK values. Muscle biopsies were performed and hematoxylin & eosin stain and Masson's trichrome stain were done. Muscle fiber diameters were measured using an eye piece micrometer of 100 fibers in each biopsy, these values were plotted and histograms were constructed. From this, mean fiber diameter (MFD), standard Deviation (SD), atrophy factor (AF), hypertrophy factor (HF) and variability coefficient (VC) were calculated. Degree of inflammation was scored semiquantitatively and presence of degenerating fibers, regenerating fibers, perifascicular atrophy, perivascular lymphocytic infiltration and vasculitis were noted. Out of 25 patients, 9 patients of inflammatory myopathy were adults, of the 16 patients of dystrophy 9 patients were adults. Along with weakness of limbs, skin rash was seen in 2 patients of dermatomyositis. Degree of inflammation was more in the patients of inflammatory myopathy than in the patients of dystrophy. Necrotic and regenerating fibers were seen in both groups. Perifascicular atrophy was seen in 1 case of dermatomyositis. Atrophy factor was higher in cases of dystrophy and so was hypertrophy factor. Variability coefficient >250 was found on 90% of dystrophy cases and it was <250 in the cases of inflammatory myopathy. Morphometry provides valuable data, which helps in distinguishing dystrophy from cases of myopathy with inflammation.