Mitochondrial myopathies-clinicopathological features and diagnostic modalities.

Mitochondrial myopathy is the term applied to a clinically and biochemically heterogeneous group of disorders which have multisystem involvement. The concept was introduced by Luft in 1962. These are due to genetic defects in the respiratory chain enzymes which are detected by histochemical, immunohistochemical stains, molecular biological studies and ultrastructural studies on muscle biopsy. Classification of the disorders can be genetic, based on defects of respiratory enzyme complexes or on the basis of the clinical syndromes. Due to the extremely variable clinical presentations of these disorders, a complete clinical and laboratory workup involving strict diagnostic criteria is essential.

Beta-sarcoglycanopathy.

Sarcoglycanopathies are relatively rare progressive muscular dystrophies with autosomal recessive inheritance; which belong to the group of limb girdle muscular dystrophies. The phenotype resembles dystrophinopathies due to proximal muscle weakness and calf hypertrophy. Reports from the Indian subcontinent are scarce. The authors report a case of primary beta-sarcoglycanopathy and describe literature pertaining to this rare entity.

Cerebellar liponeurocytoma--a case report.

Cerebellar liponeurocytomas have been included in the 2000 classification of tumours of the central nervous system, under the heading of glioneuronal tumours. The tumour has two populations of cells- one composed of cells with morphology of neurocytes and the other are lipidised cells which look like mature fat cells. The tumour occurs in adults and has a good prognosis. Less than fifteen cases have been reported in world literature. We report a case of this rare tumour entity in a 32 years old female patient.

Histological spectrum of ependymomas and correlation of p53 and Ki-67 expression with ependymoma grade and subtype.

BACKGROUND: Clinical and histological criteria for ependymoma prognosis are well recognized. Recently few studies have been done based on Immunohistochemistry for prognostication of these tumours. In this study we have correlated the histological spectrum with immmunoexpression of p53 and Ki67 in these tumors. AIMS: To know the incidence of ependymomas; study their morphological spectrum and to evaluate expression of P53 and Ki 67 in different morphological subtypes. MATERIAL AND METHOD: A retrospective study was preformed on 70 ependymomas received in a period between 1994 and 2001. Entire tissue received was processed for routine paraffin embedded H&E stained sections. Immunocytochemistry was performed using antibodies to GFAP, EMA, Pancytokeratin and synaptophysin, to differentiate papillary ependymoma from choroid plexus papilloma; clear cell ependymoma from oligodendroglioma and central neurocytoma; ependymoblastoma from other embryonal tumours. p53 and Ki-67 immunohistochemistry was performed to correlate their expression with various tumour grades and subtypes. RESULTS: There were 3 cases (4.2%) of Grade I ependymoma (2 cases of myxopapillary ependymoma and 1 case of subependymoma); 57 cases (81.5%) of ependymoma grade II (43 of these were of classical variety, 11 of clear cell ependymoma, 2 of papillary and 1 case of cellular ependymoma). There were 9 cases (12.8%) of anaplastic ependymoma (one of these was a clear cell ependymoma and 1 case (1.5%) of ependymoblastoma CONCLUSION: p53 and Ki67 indices can be used in routine diagnostic laboratories to supplement the tumor grade on histology and more studies with follow up should be performed to analyse the prognosis of different subtypes. The expression of Ki 67 and p53 was significantly higher in anaplastic ependymomas. 4 out of 11 cases of clear cell ependymomas showed higher Ki 67 indices as compared to classical grade II ependymomas, thus further highlighting the importance of differentiating the various subtypes.

Histological analysis of cystic tumour like lesions of central nervous system.

True cysts of the central nervous system (CNS) are rare lesions. A retrospective study of patients with symptomatic non-neoplastic cystic lesions of CNS operated in the Department of Neurosurgery, G.B. Pant Hospital, New Delhi between Jan 1994 and Feb 2001 was conducted. Parasitic cysts, cystic transformation of hemmorhages, vascular malformations and cystic tumours were excluded from the study. A total of 109 cases were reviewed. There were 34, 27, 17, 16, 8, 3 and 2 cases of epidermoid, arachnoid, dermoid, colloid, neurenteric, Rathke's and ependymal cysts and 1 case each of choroid plexus and glial cysts. The clinical presentations, locations, incidence and pathogenesis of these cysts is discussed.