Immunohistochemical Analysis of Paediatric Small Round Blue Cell Tumours at the Tertiary Care Centre, Ludhiana, India

Introduction: Small, undifferentiated cells with high nuclear -to-cytoplasmic ratios predominate in Small Round Blue Cell Tumours (SRBCT) and are characterised by their monotony. The classification of small round-cell tumours is further facilitated by Immunohistochemistry (IHC). Determine the line of differentiation using IHC, which also acts as a proxy for underlying molecular genetic changes. To identify the presence of a particular protein marker that can help with accurate cancer categorisation and diagnosis, histology uses IHC. In light of this, SRBCT are a sub-group of highly aggressive malignant neoplasms that are primarily comprised of monotonous, small, undifferentiated cells with high nuclear-to-cytoplasmic ratios.Aim: The study is aimed to analyse the role of IHC in the SRBCT to differentiate and accurately diagnose the tumour cells using molecular markers.Materials and Methods: This ambispective was conducted from August 1st, 2010 to 31 st July 2015, a total of five years. All specimens of SRBCT less than 18 years of age were analysed grossly and microscopically. The study covered patients who were in the paediatric age range. The study did not include the small, spherical, blue-cell tumours of the bone marrow. The SRBCT were distinguished and categorised using immunohistochemical staining. CD99, CD20, CD15, CD30, CD3, desmin, CD45/LCA (the Lymphocyte Common Antigen), chromogranin, Myogenin, Synaptophysin (SYP), Cytokeratin (CK), and Epithelial Membrane Antigen (EMA) were among the immunomarkers used in this investigation.Results: Total 54 cases of SRBCT were analysed. This included 12 cases of Non Hodgkin's Lymphoma (NHL), 10 cases of Ewing/Primitive Neuroectodermal Tumours (PNETs), 12 cases of Hodgkin's Lymphoma (HL), nine cases of rhabdomyosarcoma, four cases of neuroblastoma, two cases each of Langerhans Cell Histiocytosis (LCH) and synovial sarcoma, and one case each of olfactory neuroblastoma, sarcoma and ganglioneuroblastoma. Conclusion: This study shows that utilising IHC in challenging circumstances is incredibly helpful and crucial where clinical-histomorphological findings are not sufficient for arriving at the final diagnosis. The majority of SRBCT developed in younger age groups, with lymphoma being the most prevalent type.