Abstract
Introduction: Medulloblastoma is the most common of embryonal tumors and most malignant CNS tumor arising in childhood. 4 core molecular subtypes of medulloblastoma are defined named as WNT (Wingless pathway), SHH (Sonic Hedgehog), Group 3 and Group 4.WNT subgroup is best documented and distinguished by nuclear β catenin immunostaining, Catenin β 1 mutations, chromosome 6 loss, alongside its associated favorable prognosis.
Materials and Methods: A laboratory based descriptive type of observational study was carried out in our institute during the year 2017-2018. Total 60 specimens of medulloblastoma were taken. Details about clinical history, histopathological examination and immunohistochemistry were taken and analyzed.
Results: Medulloblastoma studied showed male predominance with highest prevalence in 1-10 years age group. Classic subtype was most common and most common site was midline. β catenin immmunoexpression was studied in all specimens, it was cytoplasmic positive in 40 cases and negative in 20 cases. Its expression is correlated with various epidemiological variables like age, sex, desmoplasia, apoptosis, anaplasia, necrosis etc., however no significant statistically difference was seen in relation to these variables.
Conclusion: Studies aimed at correlating treatment protocols and outcome with these histological and molecular subtypes are warranted to optimize treatment protocols and for prognostication. While we utilized antibody β-catenin to identify the WNT subtype of medulloblastomas, a larger panel of antibodies like GAB-1, YAP-1 and β Catenin are required to better characterize this heterogeneous group of tumors.
Keywords: Medulloblastoma, b Catenin, Immunohistochemistry.
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Corresponding Author
Dr Karuna Gupta
Professor, Department of Pathology, SMS Medical College, Jaipur, Rajasthan, India
Phone number: 9413900110, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
DOI: https://dx.doi.org/10.18535/jmscr/v7i3.77
