Although several prognostic factors in nivolumab therapy have been reported in recurrent or metastatic head and neck cancer (RM-HNC) patients, these factors remain controversial. Here, we conducted a multicenter retrospective cohort study to investigate the impact of clinico-hematological factors on survival in RM-HNC patients treated with nivolumab. We reviewed 126 RM-HNC patients from seven institutes. We evaluated the prognostic effects of clinico-hematological factors on survival. The median overall survival (OS) was 12.3 months, and the 1 year-OS rate was 51.2%. Patients without immune-related adverse events, lower relative eosinophil count, worse best overall response, higher performance status, and higher modified Glasgow Prognostic Score had worse survival. The score, generated by combining these factors, was associated with survival. Patients with score of 4–5 had worse survival than those with score of 2–3 and 0–1 [adjusted HR for PFS: score of 4–5, 7.77 (3.98–15.15); score of 2–3, 3.44 (1.95–6.06), compared to score of 0–1], [adjusted HR for OS: score of 4–5, 14.66 (4.28–50.22); score of 2–3, 7.63 (2.29–25.37), compared to score of 0–1]. Our novel prognostic score utilizing clinico-hematological factors might be useful to establish an individual treatment strategy in RM-HNC patients treated with nivolumab therapy.

Immune checkpoint inhibitors (ICIs) have become the standard treatment for recurrent or metastatic head and neck cancer (RM-HNC). However, many patients fail to benefit from the treatment. Previous studies have revealed that tumor burden predicts the efficacy of ICIs, but this association remains unclear for RM-HNC. We retrospectively analyzed 94 patients with RM-HNC treated with ICI monotherapy. We estimated the tumor burden using the baseline number of metastatic lesions (BNML) and the baseline sum of the longest diameters of the target lesions (BSLD), and evaluated the association between BNML, BSLD, and standardized uptake value (SUV) and clinical outcomes. The median progression-free survival (PFS) was 7.1 and 3.1 months in the low-BNML and high-BNML groups, respectively (p = 0.010). The median PFS was 9.1 and 3.5 months in the low-BSLD and high-BSLD groups, respectively (p = 0.004). Moreover, patients with high SUVmax levels had worse overall survival (OS) and PFS. BNML, BSLD, and SUVmax are useful prognostic factors in patients with RM-HNC treated with ICIs. Imaging examinations before ICI treatment are recommended to predict the efficacy of ICIs. If the tumor burden is high, cytotoxic anticancer agents may be administered concomitantly with or prior to ICI monotherapy.

Prognosis for advanced oral carcinoma remains poor. Oncolytic virotherapy uses replication-competent viruses to infect and kill only the tumor cells. However, it has been difficult to investigate the oncolytic activity of viruses against oral carcinomas in mouse models. This study established a mouse model of oral cancer and investigated the in vitro and in vivo anti-tumor effects of HF10, a highly attenuated, replication-competent herpes simplex virus (HSV)-1. Mouse tongue cancer was induced by injecting 4-nitroquinoline 1-oxide into the mouse tongue. The murine oral cancer cell line isolated from this tumor, named NMOC1, formed invasive carcinoma within a week when injected into mouse tongue. HF10 successfully infected, replicated, and spread in the cancer cells in vitro. HF10 was able to kill cancer cells isolated from human or mouse tongue tumor. HF10 injection into tongue carcinomas prolonged mouse survival without any side effects or weight loss. Intertumoral injection of GFP-expressing HF10 confirmed that viral spread was confined within the tumors. Immunohistochemical staining showed that HF10 induced infiltration of CD8-positive T cells around HSV-infected cells in the tumor mass, implying increased anti-tumor immunity. We successfully established an oral cancer cell line and showed that HF10 is a promising therapeutic agent for oral cancer.

Although several prognostic factors in nivolumab therapy have been reported in patients with recurrent or metastatic head and neck cancer (RM-HNC), these factors remain controversial. Here, we conducted a multicenter retrospective cohort study to investigate the impact of clinico-hematological factors on survival in RM-HNC patients treated with nivolumab. We retrospectively reviewed 126 RM-HNC patients from seven institutes. We evaluated the prognostic effects of clinico-hematological factors on survival using Cox proportional hazard models. The median overall survival (OS) was 12.3 months, and the 1 year-OS rate was 51.2 %. Patients without immune-related adverse events, lower relative eosinophil count, worse best overall response, higher performance status, and higher modified Glasgow Prognostic Score had significantly worse survival rates. The prognostic score, generated by combining these significantly worse prognostic factors, was more closely associated with prognosis than each factor (p for trend<0.001). Our novel prognostic score utilizing clinico-hematological factors might be useful to establish an individual treatment strategy in patients with RM-HNC treated with nivolumab therapy.