Background: Disease affecting Lymph nodes form wide range of spectrum from simple to malignant pathology. Such cases are an important element to rule out malignancy in early stages. However Generalised Lymphadenopathy diagnosis become huge challenge. Hence an insight into clinocohistopathological correlation with help of IHC markers becomes highly important to decide morphologic differential diagnosis.

Aims and Objectives: To study lymph node lesions with clinicohistopathological correlation with the help of IHC study.

Case Report: This is a combined observational and prospective study held in District hospital Vijayapur during August 2022 to September2023. Patient details were taken with the questionnaires. During his first visit clinical examinations and investigations, CBC, PS study, FNAC of left lower cervical region, Urine routine, chest X-ray & USG of abdomen performed and patient was analyzed & diagnosed as Chronic appendicitis and treated. During patient’s second visit, clinical examinations and  investigations CBC, PS study, FNAC of left Axillary swelling, Urine routine, chest X-ray, USG of neck & abdomen, CT Neck & abdomen, USG guided FNAC of Liver, Bone marrow  aspiration  study, Biopsy of left lower Cervical lymph node for Histopathology study & IHC study performed. Case was studied using routine H&E, PAP stain slides of Biopsy material were evaluated by light microscopy. And for IHC, patient biopsy material referred to higher center, using specific monoclonal or polyclonal antibodies, paraffin sections were stained immunohistochemically(IHC) using a Peroxidase antiperoxidase (PAP) technique in referred higher center. Result: Patient was diagnosed as B-cell Lymphoma as per WHO guidelines with the help of IHC markers. 

Conclusion: From this study, concluded  that IHC plays a significant role clinicopathology and helped in the definitive diagnosis and typing of tumour and appropriate treatment can be planned.

Keywords: Lymph node, Immunohistochemistry, Tumour.