Investigation of PD-L۱ Expression in Various Non-Hodgkin's B-cell Lymphomas

Background & Objective: Programmed death ligand-۱ (PD-L۱) plays a critical role in tumor immune evasion, particularly in Non-Hodgkin’s B-cell lymphomas (NHL). This study aimed to evaluate PD-L۱ expression across various NHL immunophenotypes and assess its correlation with clinical and demographic parameters.Methods: In this cross-sectional, descriptive-analytical study, ۷۱ formalin-fixed, paraffin-embedded tissue blocks diagnosed with Non-Hodgkin’s B-cell lymphoma were retrieved from the pathology archives of Alzahra Hospital and Seyed-al Shohada (Omid) Hospital in Isfahan (۲۰۱۹–۲۰۲۰). PD-L۱ expression was assessed immunohistochemically using tumor proportion score (TPS), combined proportion score (CPS), and immune cell (IC) score. Statistical analysis was performed using the Mann-Whitney U and Kruskal-Wallis tests, with p < ۰.۰۵ considered statistically significant.Results: Among the ۷۱ patients, ۶۷.۶% were male, with a mean age of ۵۲.۶۱ ± ۱۸.۴۳ years. Diffuse large B-cell lymphoma (DLBCL) was the most common subtype, accounting for ۵۲.۱% of cases. PD-L۱ expression was significantly higher in females (TPS: ۱۸.۱۳ ± ۹.۷۳; CPS: ۲۸.۲۲ ± ۱۳.۳۱) compared to males (TPS: ۴.۴۲ ± ۳.۵۶; CPS: ۱۲.۰۸ ± ۱۰.۱۴) (p = ۰.۰۴۰, p = ۰.۰۲۲). No significant differences in PD-L۱ expression were observed across age groups. DLBCL demonstrated significantly higher IC and CPS values compared to other subtypes (p < ۰.۰۵), while plasmacytoma and Burkitt lymphoma exhibited the lowest scores (e.g., immune score: ۱.۱۱ ± ۰.۱۱ for plasmacytoma). No statistically significant differences in TPS were noted among the different immunophenotypes (p = ۰.۱۱۹).Conclusion: Elevated PD-L۱ expression, particularly in immune cell scores, suggests potential utility in PD-۱/PD-L۱–targeted therapies for NHL. However, the prognostic significance of PD-L۱ remains inconclusive, highlighting the need for further investigation into its role as a predictive biomarker in the clinical management of Non-Hodgkin’s B-cell lymphomas.

کلیدواژه ها:

PD-L۱ ، Non-Hodgkin’s Lymphoma ، immunophenotype ، Immunohistochemistry ، DLBCL ، CANCER IMMUNOTHERAPY