Determining PD-L1 expression in head and neck squamous cell carcinoma using immunohistochemistry.

Background: Advanced head and neck squamous cell carcinoma (HNSCC) has limited treatment options. Programmed death-ligand1 (PD-L1) expressed by tumor cells interacts with PD-1 receptor on T lymphocytes leading to immune evasive response and survival advantage. Therapy with immune check-point inhibitors target PD-1/PD-L1 blockade inducing tumor regression. Immunohistochemistry (IHC) for PD-L1 expression enables patient selection for immunotherapy and may be considered a potential predictor of clinical response. Methods: A retrospective analysis of IHC for PD-L1 expression using manual laboratory developed technique (LDT) with antibody clone 22C3 (Dako) in 93 cases of HNSCC. PD-L1 expression was correlated with age, gender, tumor site, grade and stage. Results: PD-L1 IHC was performed in 93 cases and immunopositivity was noted in 59 (63.4%) cases. High expression with combined proportion score (CPS) ≥50 was seen in 15 (16.1%) cases and low expression with CPS ≥1 expression was seen in 44 (47.3%) cases. An almost-perfect interobserver agreement was noted by two pathologists for PD-L1 IHC expression (Cohen's kappa coefficient = 0.910). No statistically significant correlation was noted between PD-L1 score and patient demographics, tumor site, grade or stage. Conclusion: Detection of PD-L1 status by IHC enables identification of HNSCC patients eligible for future targeted immunotherapy.

Weight Loss as a Nutritional Indicator in Head and Neck Cancer Patients Undergoing Chemoradiotherapy: Contributing Factors and Its Impact on Disease Outcome.

This is a retrospective study carried out at a tertiary care cancer center to assess weight loss in patients of head and neck cancers (HNCs) during treatment with chemoradiotherapy (CRT) and study various factors affecting it. Treatment and follow-up records of 77 patients of HNCs were studied and assessed for demographic, disease-specific variables, treatment parameters, weight loss during CRT, as well as survival at 2 years after treatment completion. A statistical analysis was conducted to assess the association of study variables with weight loss. It was also assessed if a correlation existed between weight loss during treatment and patient survival at 2 years. Of the study patients, 62.3% (48) suffered 5% or more weight loss during CRT while 23.4% (18) suffered a weight loss of 10% or more. No particular factor was identified having a statistically significant association with weight loss. Nutritional impairment is an important factor affecting the morbidity and possibly the mortality of patients of HNCs undergoing CRT. More robust studies are required to identify which factors affect weight loss during treatment and whether weight loss can be used as a parameter to prognosticate patients.