The neutrophil to lymphocyte ratio (NLR) has been widely investigated for its prognostic significance in cancer. it may be BRG1 an independent prognostic factor for disease-free survival and breast cancer-specific survival in patients with breast cancer. It has also been demonstrated that increased pretreatment NLR is an independent prognostic factor in patients with metastatic renal cell carcinoma who received tyrosine Taladegib kinase inhibitors (14). When evaluating the association between NLR and HNSCC, it was previously demonstrated Taladegib that high pretreatment peripheral NLR was significantly associated with poor PFS among patients with advanced clinical stage (III and IV) nasopharyngeal carcinoma (7). However, there was no significant association between NLR and PFS in the present study. Apart from the limited number of studies on nasopharyngeal carcinoma, there are no studies in the literature demonstrating the prognostic significance of NLR in head and neck carcinomas, mainly laryngeal carcinoma. In another study on oral cavity cancer patients, it was observed that NLR increased in parallel with the advancement of clinical stage and T stage, but it was not significantly associated with survival (18). Furthermore, the opposite finding has also been reported, namely better survival associated with higher NLR in HNSCC patients, suggesting an antitumorigenic role of NLR (19). Rassouli (20) reported that NLR 4.2 predicts a higher recurrence rate (P<0.0001, log-rank test) and concluded that NLR may be used as an independent predictor of recurrence and survival. A retrospective study on pretreatment NLR and disease-spesific survival in patients with oral cancer undergoing preoperative chemoradiotherapy indicated that NLR is a significant independent predictor of poor cancer-specific survival (21). In accordance with the literature regarding cancer types other than HNSCC, our results also identified Taladegib NLR as an independent prognostic factor in patients with recurrent or metastatic HNSCC. NLR derived from a single blood sample at initial diagnosis of metastatic disease or at recurrence may be a useful laboratory marker for recurrent or metastatic HNSCC. This simple, cost-effective, non-invasive and rapidly available test may be easily used in clinical practice. Combined with other markers, NLR may be used in decision-making and the selection of treatment modality in patients with recurrent or metastatic HNSCC. Although the present study was a retrospective, single-center study, it indicates the potential benefit of a novel prognostic marker in HNSCC. However, our Taladegib findings require confirmation by larger, prospective, randomized studies..