Spectrum of Gastric Carcinoma in a Tertiary Care Centre with Special Reference to PDL1 and Cyciln D1

Introduction: Gastric carcinoma is the fifth most frequently diagnosed tumor and the fourth leading cause of death. They represent a heterogenous group of tumors with multifactorial etiologies, both environmental and genetic. PD-L1 is a transmembrane protein, and a positive PD-L1 expression in gastric carcinoma may be a predictive biomarker of the response to PD-1/PD-L1 immune checkpoint inhibitors. Cyclin D1 is an important cell cycle regulatory protein and involved in the carcinogenesis of various cancers including gastric cancer. Aims: The aim of this study is to find out the clinicopathological spectrum of gastric carcinoma and to show the immunohistochemical expression of Cyclin D1 and PD-L1 to evaluate their prognostic importance and their therapeutic impact. Study Design: It is an observational cross-sectional study conducted in the Department of Pathology in collaboration with the Department of Surgery, in a tertiary care hospital. Partial and total gastrectomies were selected from January 2021 to July 2022 in a tertiary care hospital. Clinical history was collected in the study proforma. Immunohistochemical staining for Cyclin D1 and PD-L1 was performed. Material and Methods: The clinicopathological parameters like age, gender, histological type, regional lymph node status, lymphovascular invasion, perineural invasion, and pathological stage were compared and correlated with Cyclin D1 and PD-L1 expression. Results: Positive Cyclin D1 and PDL1 expression were found in 50% and 70% cases of gastric carcinoma, respectively. Cyclin D1 expression showed statistically significant correlation with anemia, regional lymph node status, and lymphovascular invasion. PD-L1 and Cyclin D1 expression showed statistically significant association between them (p value-0.0006). Conclusion: Cyclin D1 and PDL1 are important biomarkers in gastric carcinoma. Their contribution towards prediction of progression and prognosis, along with newer therapeutic modalities, is of immense importace in these patients. A statistically significant correlation was found between these two markers.