Cancer and immune response: The role of PD-1/PD-L1 checkpoint in laryngeal carcinoma. Preliminary results

Purpose: The overall survival of laryngeal squamous cell carcinoma (LSCC) hasn't changed significantly in the last decades, leading to a negative prognosis in advanced stages. So, the immunotherapy takes space with the inhibition of PD-1/PD-L1 checkpoint, involved in suppression of immune response. Methods: A prospective study was conducted on LSCC patients, selected according to strict criteria. The study was approved by the ethics committee of our Hospital. Parameters were: sex, age, smoking and alcohol habits, C-reactive protein (CRP) level in the serum, laryngeal subsite involved, differentiation-based histopathologic grading of tumor, neck node involvement, tumor stage, expression levels of PD-L1 (as Combined Positive Score - CPS). P-value < 0.05 was statistically significant. Results: 58 patients were included: 31.03% were females, mean age 63.55±10.09. A statistically significant correlation between CPS and smoking habits and N stage was found. CRP resulted increased in 44.83% of patients with a statistically significant correlation with CPS. The most cases were glottic cancers (46.55%). 75.86% of tumors were moderately-differentiated, without correlation with CPS. Conclusion: PD-L1 expression levels are variables independent of sex, age, alcohol consumption, differentiation degree of LSCC. A statistically significant correlation between PD-L1 expression levels and smoking habits, neck node status and CRP was found. This last finding demonstrates the involvement of PD-1/PD-L1 checkpoint in immune response in case of cancer. However, these results need further studies to detect the best patients tailored for treatment with anti-PD-1/PD-L1 blocking antibodies.