Correction: Effectiveness and safety of weekly paclitaxel and cetuximab as a salvage chemotherapy following immune checkpoint inhibitors for recurrent or metastatic head and neck squamous cell carcinoma: a multicenter clinical study.

[This corrects the article DOI: 10.1371/journal.pone.0271907.].

Immune Checkpoint Inhibitors for Nasopharyngeal Carcinoma in a Real-world Setting in Japan.

BACKGROUND/AIM: The advent of immune checkpoint inhibitor (ICI) treatment has transformed the treatment of recurrent or metastatic head and neck cancer; however, nasopharyngeal carcinoma (NPC) has not been included in major phase III trials. The clinical outcomes of ICI for NPC in real-world practice remain to be fully elucidated. PATIENTS AND METHODS: We retrospectively reviewed 23 patients with recurrent or metastatic NPC treated with nivolumab or pembrolizumab at 6 institutions from April 2017 to July 2021 and investigated the correlation of clinicopathological factors and immune-related adverse events with the effects of ICI therapy and the prognosis. RESULTS: The objective response rate was 39.1% and the disease control rate was 78.3%. The median progression-free survival was 16.8 months and overall survival has not been reached. As with other treatment procedures, the efficacy and the prognosis tended to be better in EBER-positive cases than in EBER-negative cases. The rate of significant immune-related adverse events that necessitated discontinuation of treatment was only 4.3%. CONCLUSION: ICI monotherapy (e.g., nivolumab and pembrolizumab) was effective and tolerable for NPC in a real-world setting.

Effectiveness and safety of weekly paclitaxel and cetuximab as a salvage chemotherapy following immune checkpoint inhibitors for recurrent or metastatic head and neck squamous cell carcinoma: A multicenter clinical study.

OBJECTIVES: The benefit of sequential therapy after immune checkpoint inhibitor (ICI) treatment for recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) has been recently reported. Furthermore, there is a growing interest in the impact of cetuximab (Cmab)-containing salvage chemotherapy (SCT) and the therapeutic efficacy and adverse events (AEs) of Cmab administration prior to ICI administration. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 52 patients with R/M HNSCC treated with SCT (weekly paclitaxel [PTX], n = 7, or weekly PTX and Cmab [PC], n = 45). RESULTS: The objective response rate (ORR) and a disease control rate (DCR) was 53.3% and 91.1% in the PC group and 42.9% and 57.1% in the PTX group, respectively. There was a significant difference in the DCR between the PC and PTX groups (p = 0.0143). The overall survival (OS) and progression-free survival were significantly better in the PC group than in the PTX group. On the other hand, the incidence of drug-induced interstitial pneumonia (DI-IP) in R/M HNSCC patients who received SCT was 21.2%. Patients in the PC group were divided according to whether they received Cmab (Group A) or did not receive Cmab (Group B) as palliative therapy prior to ICIs. Group B had a significantly better OS than Group A. Furthermore, our findings suggest that the incidence rate of DI-IP during SCT might be higher in Group B. CONCLUSION: Although PC following ICIs shows dramatic efficacy, careful monitoring of AEs, including DI-IP, is recommended.

Real-world Experience With Pembrolizumab for Advanced-stage Head and Neck Cancer Patients: A Retrospective, Multicenter Study.

BACKGROUND/AIM: This study investigated the effectiveness of pembrolizumab with or without chemotherapy on advanced-stage head and neck cancer (HNC), including nasopharyngeal, sinonasal cavity and external auditory canal cancer, in a real-world setting. PATIENTS AND METHODS: We retrospectively collected data from 97 HNC patients who were treated with pembrolizumab alone (n=60) or with chemotherapy (n=37), and we investigated the association between clinicopathological findings and treatment response or prognosis. RESULTS: Patients treated with pembrolizumab and chemotherapy had a 1-year overall survival (OS) of 72.8%, objective response rate (ORR) of 48.6%, and serious (≥G3) adverse events (AEs) of 29.7%. Patients treated with pembrolizumab alone had a 1-year OS of 51.9%, ORR of 21.7%, and ≥G3 AEs of 6.7%. Both the ORR and disease control rate (DCR) in the pembrolizumab with chemotherapy group were significantly better than those in the pembrolizumab group (p=0.074 and p=0.00101, respectively). Among patients with distant metastasis, patients on pembrolizumab with chemotherapy achieved significantly better OS than pembrolizumab alone (p=0.0039). Among patients in the pembrolizumab group, both AE-positive and better performance status were associated with longer OS (p=0.011 and p=0.0037, respectively). CONCLUSION: Our real-world experience reinforces the durability and effectiveness of pembrolizumab for HNC patients. Additionally, our results suggest that pembrolizumab with chemotherapy might be recommended for patients with distant metastasis and no prior treatment. Further studies are needed to determine the optimal treatment strategy for HNC.

Retrospective Study of Cisplatin/Carboplatin, 5-Fluorouracil Plus Cetuximab (EXTREME) for Advanced-stage Salivary Gland Cancer.

BACKGROUND/AIM: Surgery remains the standard treatment for salivary gland carcinoma (SGC). Our study investigated the association between epidermal growth factor receptor (EGFR) status in recurrent/metastatic SGC and the effectiveness of treatment with cisplatin/carboplatin and 5-fluorouracil plus cetuximab (EXTREME). PATIENTS AND METHODS: We retrospectively collected 19 SGCs from patients treated with the EXTREME regimen. After analyzing EGFR expression and gene copy number gain, we evaluated the correlation between EGFR status and clinicopathological factors and prognosis. RESULTS: EGFR overexpression was detected in 77.8% cases, but not statistically associated with clinicopathological factors or prognosis. EGFR gene copy number gain was detected in 16.7% cases, and statistically positively correlated with lymph node metastasis (p=0.0291). The best overall response was partial response in two cases, stable disease in 15, and progressive disease in one case. The EXTREME regimen was discontinued in all cases. CONCLUSION: Our results suggest that SGCs are positive for EGFR protein expression but the response rate to the EXTREME regimen was unremarkable.

Treatment Efficacy of PD-1 Inhibitor Therapy in Patients With Recurrent and/or Metastatic Salivary Gland Carcinoma.

BACKGROUND/AIM: The efficacy of programmed cell death 1 (PD-1) inhibitor therapy for patients with recurrent and/or metastatic salivary gland carcinoma (R/M SGC) remains unclear. PATIENTS AND METHODS: We retrospectively analyzed 36 patients with R/M SGC treated with PD-1 inhibitor. The expression of programmed cell death ligand 1 (PD-L1) and mismatch repair (MMR) proteins was also analyzed. RESULTS: The objective response rate (ORR) was 11.1%. The histopathological subtypes of patients who achieved complete response or partial response were salivary duct carcinoma (SDC) in three patients and poorly differentiated carcinoma in one patient, all of whom showed a positive PD-L1 expression. The expression of MMR proteins was not associated with the efficacy of PD-1 inhibitors. CONCLUSION: Although the efficacy of PD-1 inhibitor therapy in R/M SGC is limited, certain patients may respond and achieve long-term disease control. There is a potential therapeutic effect in SDC patients with positive PD-L1 expression.

Prognostic Biomarkers of Salvage Chemotherapy Following Nivolumab Treatment for Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma.

Recent studies have suggested the benefit of salvage chemotherapy (SCT) after immune checkpoint inhibitor (ICI) treatment for recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). We retrospectively examined the outcome of SCT and the usefulness of the serum C-reactive protein level (CRP) and neutrophil-to-lymphocyte ratio (NLR) as prognostic biomarkers. Thirty-nine patients with R/M HNSCC were enrolled in this study. Twenty-five patients (64.1%) received combination chemotherapy of weekly paclitaxel and cetuximab (PC) as SCT, and 14 patients (35.9%) received tegafur-gimestat-otastat potassium (S1), an oral fluoropyrimidine. In all patients, the response rate, disease control rate, median progression-free survival (PFS), and median overall survival (OS) were 45.2%, 85.7%, 6.5 months, and 13.5 months, respectively. No chemotherapy-related deaths were observed. These PC groups had low CRP (<1.2 mg/dL) or low NLR (<7.0) values at the time of SCT induction, which was significantly associated with an improved OS (p = 0.0440, p = 0.0354). A multivariate analysis also showed that a lower CRP value was significantly associated with a better OS (p = 0.0078). We clarified the usefulness of the PC and S1 regimens as SCT. In addition, SCT with the PC regimen showed a better prognosis with a lower CRP or NLR at induction than a higher CRP or NLR. This is the first report on biomarkers of SCT in R/M HNSCC.

Clinical outcome in recurrent and/or metastatic head and neck cancer patients after discontinuation of nivolumab monotherapy due to immune-related adverse events.

BACKGROUND: Significant immune-related adverse events (irAEs) requiring therapy discontinuation sometimes occur. The influence of discontinuation on disease control after an irAE is unclear. OBJECTIVES: The aim of this study was to investigate whether or not patients continued to show a response or durable disease control even after stopping therapy following an irAE. MATERIAL AND METHODS: The response after nivolumab monotherapy discontinuation was examined for 14 patients in whom therapy was stopped without progression. RESULTS: The best response was CR in 5 (36%) patients, PR in 8 (57%) patients and SD in 1 (7%) patient. The estimated 1-year overall and progression-free survival rates were 92.9% and 78.6%, respectively. The best response during nivolumab therapy in patients who developed PD was CR in 0 of 5 patients (0%), PR in 3 of 8 patients (38%) and SD in 1 patient (100%). Patients obtaining CR tended to have a lower risk of PD than those with PR or SD. CONCLUSIONS AND SIGNIFICANCE: Patients with CR status may continue to show a response or durable disease control even after stopping therapy due to an irAE.

A Case of Salivary Duct Carcinoma Intracranial Invasion due to Perineural Invasion Through the Facial Nerve.

BACKGROUND: Salivary duct carcinoma (SDC) is a rare parotid tumor that often develops as a rapidly growing mass with a poor prognosis. It has a high rate of distant metastases, sometimes with infiltration along nerves. We describe a case of SDC that originated outside the cranium and extended into the cranium along the path of the facial nerve. CASE DESCRIPTION: A 74-year-old man underwent magnetic resonance imaging at a local hospital, which revealed a tumor in the left internal acoustic canal; the patient was referred to our department. A left facial schwannoma was suspected, and magnetic resonance imaging was performed again 6 months later. Rapid tumor growth was confirmed, and the tumor was resected. The tumor displayed atypical epithelial cells with comedo necrosis and cribriform structure and was diagnosed as SDC. All residual intracranial tumors were removed using the middle fossa approach. The tumor, which was considered to be a primary tumor, was found near the stylomastoid foramen, and it was removed with the parotid gland. Five months after the initial surgery, metastasis to the trigeminal nerve was observed, and this was removed using a retrosigmoid approach, followed by radiation therapy. CONCLUSIONS: All 4 surgical specimens of this case were presented, and the path of tumor progression was examined in detail. Although the primary lesion was small, intracranial invasion along the facial nerve occurred. SDC should be considered as a tumor that can extend into the cranium, even with a small primary lesion.