Programmed Death Ligand 1 (PD-L1) expression in invasive cervical cancer: A single institution study

Background Cervical cancer (CC) remains one of the most common malignancies in women worldwide. The immune checkpoint PD-L1 is one of the important players in immunosuppression in the tumor microenvironment of CCs. The objectives of the present study were to determine the expression profile of the PD-L1 protein in CC by immunohistochemistry and to study the correlations between the PD-L1 status and the clinicopathological and prognostic characteristics. Methods This was a retrospective descriptive study of 146 cases of CCs, collected at the pathological department of Salah Azaiez Institute from medical records and pathological reports. Immunohistochemistry was used to assess the expression of PD-L1 according to the protocol applied in the laboratory. Results The average age of the patients was 54 years (23-87 years). The mean tumor size was 40.7 mm (5-90 mm). The most common histological type was squamous cell carcinoma (88.3%). CCs were well differentiated in 62.6% of cases. Stage 2B was observed in 49% of cases. Vascular emboli were observed in 7.1% of cases. Concomitant radio-chemotherapy was recommended in 86.8% of the patients and brachytherapy was indicated in 79.7% of the patients. More than half of the patients were operated. Occurrence of distant recurrence was observed in 17.3% and pelvic recurrence in 20.4% of the cases. The evolution was favorable in 39.3% cases. Immunohistochemical analysis revealed PD-L1 expression in 32.4% in tumor cells and in 47.1% in the immune cells. The expression of PD-L1 in tumor cells was associated to endometrium invasion (p=0.014). Conclusion PD-L1 is expressed in CCs. No association with histoprognostic parameters has been demonstrated. Larger studies should be considered with a high number of samples to assess the correlation between PD-L1 and histoprognostic factors to support the role of this biomarker in the evolution of CCs