title: Morphological Patterns of Intracranial Lesions in a Tertiary Care Hospital in North Karnataka: A Clinicopathological and Immunohistochemical Study.
abstract: BACKGROUND
  An "Intra-cranial space occupying lesion" (ICSOL)is defined as a mass lesion in the cranial cavity with a diverse aetiology like benign or malignant neoplasm, inflammatory or parasitic lesion, haematoma, or arterio-venous malformation. Central nervous system neoplasms represent a unique, heterogenous population of neoplasms constituting 1.9% of all malignant tumours in India. A broad spectrum of non-neoplastic conditions can mimic a brain tumour, both clinically and radiologically and these patients undergo biopsy. In such cases, the pathologist can readily differentiate between neoplastic and non-neoplastic imitators.
  
  
  OBJECTIVE
  The present study attempts to provide preliminary data on morphological patterns of intracranial lesions in North Karnataka region and to study clinicopathological spectrum with correlation of radiological findings of ICSOL. Special emphasis is made on the utility of special stains and IHC markers in CNS tumours.
  
  
  METHODS
  This retrospective and prospective descriptive study was performed on biopsy specimen of ICSOL received from Departmnet of Neurosurgery, Basaveshwar Teaching Hospital, Kalaburgi. The study period was from January 2012 to June 2013 retrospectively and July 2013 to June 2015 prospectively. All specimens were preserved in 10% formalin and allowed to fix for 24 hours. The haematoxylin and eosin stained sections of the CNS lesions were obtained by routine processing and paraffin embedding. Special stains and IHC were done wherever appropriate.
  
  
  RESULTS
  Sixty two cases of CNS lesions were studied, of which 12 (19.4%) cases were non neoplastic with six (50%) being cystic lesions and four (33.4%) were cerebral abscess. The neoplastic lesions comprised of 50 (80.6%) cases, which included 48 (96%) primary and two (4%) metastatic lesions. Among primary tumours, gliomas constituted the largest category of 24 (50%) cases with 16.7% being Glioblastoma Multiforme (GBM) and pilocytic astrocytomas each, followed by schwannomas (14%) and meningothelial tumours (12%). Majority were Grade I among gliomas and tumour of meninges with 37.5% and 87.5% respectively. Mean age of the patients was 26.72±11.2 (range: 0.4 to 80) years. Male to female ratio was 1:1.14. GFAP was demonstrated in astrocytomas, mixed gliomas and gliosarcoma.
  
  
  CONCLUSIONS
  The surgical pathologist plays an important role in accurate diagnosis of various lesions of CNS which will be of immense help for patient prognosis and treatment. Immunohistochemistry is currently being employed to assist in the diagnosis of brain tumours.
authors.affiliation: Resident, Department of Pathology, MRMC , Kalaburagi, Karnataka, India .
authors.forename: Neelakantaiah Anadure
authors.initials: NA
authors.lastname: Hema
authors.affiliation: Associate Professor, Department of Neurosurgery, MRMC , Kalaburagi, Karnataka, India .
authors.forename: Ramdurg Shashank
authors.initials: RS
authors.lastname: Ravindra
authors.affiliation: Professor and Head of Department, Departmentof Pathology, MRMC , Kalaburagi, Karnataka, India .
authors.forename: Andola Sainath
authors.initials: AS
authors.lastname: Karnappa
keywords: Astrocytoma; Gliomas; Immunohistochemistry