The presence of tumor-infiltrating lymphocytes (TIL) in the tumor microenvironment has been demonstrated to be of prognostic value in various cancers. In this systematic review and meta-analysis, we investigated the prognostic value of TIL in laryngeal squamous cell carcinoma (LSCC). We performed a systematic search in PubMed for publications that investigated the prognostic value of TIL in LSCC. A meta-analysis was performed including all studies assessing the association between TIL counts in hematoxylin-eosin (HE)-stained sections, for CD8+ and/or CD3+/CD4+ TIL and overall survival (OS) or disease-free survival (DFS). The pooled meta-analysis showed a favorable prognostic role for stromal TIL in HE sections for OS (HR 0.57, 95% CI 0.36–0.91, p = 0.02), and for DFS (HR 0.56, 95% CI 0.34–0.94, p = 0.03). High CD8+ TIL were associated with a prolonged OS (HR 0.62, 95% CI 0.4–0.97, p = 0.04) and DFS (HR 0.73, 95% CI 0.34–0.94, p = 0.002). High CD3+/CD4+ TIL demonstrated improved OS (HR 0.32, 95% CI 0.16–0.9, p = 0.03) and DFS (HR 0.23, 95% CI 0.10–0.53, p = 0.0005). This meta-analysis confirmed the favorable prognostic significance of TIL in LSCC. High stromal TIL evaluated in HE sections and intra-tumoral and stromal CD3+, CD4+ and/or CD8+ TIL might predict a better clinical outcome.

Background: Tumor mutational burden (TMB) has been demonstrated to predict the response to immune checkpoint inhibitors (ICIs) in various cancers. However, the role of TMB in head and neck squamous cell carcinoma (HNSCC) has not yet been specifically addressed. Since HNSCC patients exhibit a rather limited response to ICIs, there is an unmet need to develop predictive biomarkers to improve patient selection criteria and the clinical benefit of ICI treatment. Methods: We conducted a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. HNSCC cohort studies were selected when TMB prior to ICI treatment was evaluated, TMB cutoff value was available, and the prognostic value of TMB was evaluated by time-to-event survival analysis. A total of 11 out of 1960 articles were analyzed, including 1200 HNSCC patients. Results: The results showed that those patients harboring high TMB exhibited a significantly superior overall response rate (OR = 2.62; 95% CI 1.74–3.94; p < 0.0001) and a survival advantage (HR = 0.53; 95% CI 0.39–0.71; p < 0.0001) after ICI treatment. Conclusion: This is the first meta-analysis to demonstrate a higher response and clinical benefit from ICI therapy in HNSCC patients with high TMB. Graphical

Neutrophil-to-lymphocyte ratio (NLR) has been associated with survival in various cancers, including head and neck cancer. However, there is limited information on its role in oropharyngeal squamous cell carcinomas (OPSCC) according to HPV status. This prompted the present meta-analysis. Studies were selected when the prognostic value of NLR prior to treatment was evaluated in OPSCC patients, the cutoff value of NLR was available, and the prognostic value of NLR was evaluated by time-to-event survival analysis. A total of 14 out of 492 articles, including 7647 patients, were analyzed. The results showed a worse prognosis for the patients with a high NLR: The combined hazard ratios (HR) for overall survival (OS) in patients with an elevated NLR was 1.56 (95% confidence interval (CI) 1.21–2.02; p = 0.0006), for disease-free survival was 1.52 (95% CI 1.34–1.73; p < 0.00001), and for recurrence-free survival was 1.86 (95% CI 1.50–2.30; p < 0.00001). This worse prognosis of high NLR was exclusive of HPV-positive patients: HR for OS in the HPV-positive subgroup was 4.05 (95% CI 1.90–8.62 (p = 0.0003), and in the HPV-negative subgroup 0.92 (95% CI 0.47–1.80; p = 0.82). The prognosis of NLR was not influenced by treatment: The HR for OS for patients treated with radiotherapy/chemoradiotherapy (RT/CRT) was 1.48 (95% CI 1.09–2.01; p = 0.01), and for patients treated with surgery (±RT/CRT) was 1.72 (95% CI 1.08–2.72; p = 0.02). In conclusion, an elevated NLR relates to worse outcomes in patients with HPV-positive OPSCC.

The SOX2 gene located at 3q26 is frequently amplified and overexpressed in multiple cancers, including head and neck squamous cell carcinomas (HNSCC). The tumor-promoting activity and involvement of SOX2 in tumor progression has been extensively demonstrated, thereby emerging as a promising therapeutic target. However, the role of SOX2 in early stages of tumorigenesis and its possible contribution to malignant transformation remain unexplored. This study investigates for the first time SOX2 protein expression by immunohistochemistry and gene amplification by real-time PCR using a large series of 94 laryngeal precancerous lesions. Correlations with the histopathological classification and the risk of progression to invasive carcinoma were established. Nuclear SOX2 expression was frequently detected in 38 (40%) laryngeal dysplasias, whereas stromal cells and normal adjacent epithelia showed negative expression. SOX2 gene amplification was detected in 18 (33%) of 55 laryngeal dysplasias. Univariate Cox analysis showed that SOX2 gene amplification (p = 0.046) and protein expression (p < 0.001) but not histological grading (p = 0.432) were significantly associated with laryngeal cancer risk. In multivariate stepwise analysis including age, tobacco, histology, SOX2 gene amplification and SOX2 expression, SOX2 expression (HR = 3.531, 95% CI 1.144 to 10.904; p = 0.028) was the only significant independent predictor of laryngeal cancer development. These findings underscore the relevant role of SOX2 in early tumorigenesis and a novel clinical application of SOX2 expression as independent predictor of laryngeal cancer risk in patients with precancerous lesions beyond current WHO histological grading. Therefore, targeting SOX2 could lead to effective strategies for both cancer prevention and treatment.