Expression of PDL-1 between primary and recurrent/metastatic head and neck squamous cell carcinoma: A bi-institutional retrospective concordance analysis (CONCORDL-1 study).

INTRODUCTION: Immune checkpoint inhibitors (ICIs) have demonstrated efficacy in the treatment of recurrent and/or metastatic (RM) head and neck squamous cell carcinoma (HNSCC) Keynote 048 highlighted the relevance of PD-L1 Combined Positive Score (CPS) as a predictive biomarker for ICIs treatment, but challenges persist regarding ideal assessment and concordance between primary and relapsing tumor has not been determined. MATERIAL AND METHODS: This is a retrospective multicentric study that included HNSCC patients with locoregional and/or metastatic relapses after curative treatment. Histological samples of primary tumors and corresponding relapses were collected. The primary objective was to evaluate PD-L1 CPS concordance between primary and recurrent tumors, with secondary objective of exploring the impact of clinical-pathological variables. RESULTS: Out of 86 evaluated patients, 30 cases were excluded due to insufficient histological material, with a final enrollment of 56 patients. Concordance analysis revealed a 66.1% agreement in PD-L1 CPS between primary and recurrent tumors. Only 3.6% of cases exhibited a change from negative to positive PD-L1 CPS status, and 7.2% showed the reverse. Factors analyzed, including primary tumor site, treatment modality, and recurrence type, did not significantly influence PD-L1 CPS concordance level. CONCLUSION: While significant changes in PD-L1 CPS expression are rare, the study underscores the importance of confirmatory biopsies on relapse. However, reliance on archival tumor tissue for initial PDL1 assessment may be considered in cases where obtaining additional biopsies poses risks to patients or urgent therapeutic decisions are required.

Weekly paclitaxel, carboplatin and cetuximab (PCE) combination followed by nivolumab for recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN).

OBJECTIVES: Cetuximab-based chemotherapy is a standard 1st-line treatment for recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN). However, few studies have reported survival data for a treatment sequence consisting of a PCE regimen (paclitaxel + carboplatin + cetuximab) followed by an immune checkpoint inhibitor. MATERIALS AND METHODS: We retrospectively assessed 37 patients with R/M SCCHN from the oral cavity, oropharynx, hypopharynx, and larynx who received PCE as 1st-line treatment followed by nivolumab as 2nd-line at the National Cancer Center Hospital East between December 2016 and July 2021. For comparison, we also analyzed 14 patients who did not receive nivolumab after PCE. RESULTS: Of the 37 patients who received nivolumab, overall response rate (ORR) by PCE was 48.6%, and median time to response and median progression-free survival (PFS) were 2.1 months (range: 0.8-4.8) and 4.4 months, respectively. In the nivolumab phase, ORR was 10.8%. 23 patients received 3rd-line therapy. Median PFS2, PFS3, and overall survival (OS) were 6.8, 11.6, and 19.5 months, respectively. Subgroup analysis by PD-L1 expression showed no significant difference in OS. Analysis of the comparison group revealed a trend toward improved OS in those who received nivolumab compared to those who did not (HR 0.47, 95%CI [0.19-1.13], p = 0.084). CONCLUSION: PCE followed by nivolumab shows a favorable survival outcome, representing the potential for rapid tumor response with PCE and extension of OS by the addition of nivolumab regardless of combined positive score.

The clinical impact of testing for biomarkers in gastric cancer patients: a real-world cohort.

BACKGROUND AND AIMS: In gastric cancer (GC), HER2 was the first biomarker for guided therapy registered for clinical use. Considering the recent approvals of immune check-point blockade (ICB) in gastro-oesophageal cancers, testing for mismatch repair deficiency (dMMR), Epstein-Barr virus (EBV) and PD-L1 combined positive score (CPS) is becoming increasingly important. Here we describe a real-world cohort on biomarker assessment in GC patients. METHODS: Patients diagnosed with GC between 2017 and 2021 were included. Biomarker results were retrieved from electronic patient files. PD-L1 CPS was determined retrospectively on dMMR and EBV-positive (EBV+) tumours. Data on genomic sequencing were analysed separately. RESULTS: Of 363 patients identified, 45% had metastatic disease. In 335 patients (92%) at least one biomarker was tested. The prevalence of HER2+, dMMR and EBV+ tumours was 10% (32 of 319), 7% (20 of 294) and 1% (three of 235), respectively. Of the dMMR and EBV+ tumours, 95% had a PD-L1 CPS ≥ 5. Therapeutic strategy was adjusted in 31 of 55 patients and consisted of anti-HER2 therapies as well as ICB in clinical trials. Genomic alterations were found in 44 of 60 tested patients. TP53 (73%) and PIK3CA (20%) mutations were most common, followed by KRAS mutations (11%) and amplifications (11%). CONCLUSIONS: In this real-world cohort, testing for HER2, dMMR and EBV status affected treatment decisions in 56% of the patients. Although most dMMR and EBV+ tumours had a PD-L1 CPS ≥ 5, not all patients with a high probability of treatment response are identified. Based on these results, a stepwise diagnostic strategy is proposed.

Treatment Stratification in First-Line Recurrent or Metastatic Head and Neck Cancer, on Behalf of the EORTC Young Investigator Head and Neck Cancer Group.

Multiple factors differentially influence treatment decisions in the first line treatment of recurrent/metastatic HNSCC. The EORTC Young investigator group launched a survey among treating physicians to explore the main influencing factors for treatment stratification. The questionnaire was posted as a web-survey link from May to August 2020. Next to defining the factors that mostly influence therapeutic decision the survey was complemented by a clinical case discussion of five patient cases. A total of 118 responses from 19 countries were collected. The key factors identified to guide treatment decision were performance status, PD-L1 Expression, time from last systemic treatment above or below 6 months, and disease burden. Prospective evaluation of patient characteristics and additional potential predictive biomarkers for novel treatment options remains an important question to stratify personalized treatment for RM HNSCC.

Pembrolizumab versus chemotherapy for patients with esophageal squamous cell carcinoma enrolled in the randomized KEYNOTE-181 trial in Asia.

BACKGROUND: In the randomized phase III KEYNOTE-181 study, pembrolizumab prolonged overall survival (OS) compared with chemotherapy as second-line therapy in patients with advanced esophageal cancer and programmed death-ligand 1 (PD-L1) combined positive score (CPS) ≥10. We report a post hoc subgroup analysis of patients with esophageal squamous cell carcinoma (ESCC) enrolled in KEYNOTE-181 in Asia, including patients from the KEYNOTE-181 China extension study. PATIENTS AND METHODS: Three hundred and forty Asian patients with advanced/metastatic ESCC were enrolled in KEYNOTE-181, including the China cohort. Patients were randomly assigned 1 : 1 to receive pembrolizumab 200 mg every 3 weeks for ≤2 years or investigator's choice of paclitaxel, docetaxel, or irinotecan. OS, progression-free survival, response, and safety were analyzed without formal comparisons. OS was evaluated based on PD-L1 CPS expression level. RESULTS: In Asian patients with ESCC, median OS was 10.0 months with pembrolizumab and 6.5 months with chemotherapy [hazard ratio (HR), 0.63; 95% CI 0.50-0.80; nominal P < 0.0001]. Median progression-free survival was 2.3 months with pembrolizumab and 3.1 months with chemotherapy (HR, 0.79; 95% CI 0.63-0.99; nominal P = 0.020). Objective response rate was 17.1% with pembrolizumab and 7.1% with chemotherapy; median duration of response was 10.5 months and 7.7 months, respectively. In patients with PD-L1 CPS <1 tumors (pembrolizumab versus chemotherapy), the HR was 0.99 (95% CI 0.56-1.72); the HR (95% CI) for death was better for patients with PD-L1 CPS cut-offs >1 [CPS ≥1, 0.57 (0.44-0.75); CPS ≥5, 0.56 (0.41-0.76); CPS ≥10, 0.53 (0.37-0.75)]. Treatment-related adverse events were reported in 71.8% of patients in the pembrolizumab group and 89.8% in the chemotherapy group; grade 3-5 events were reported in 20.0% and 44.6%, respectively. CONCLUSIONS: Pembrolizumab monotherapy demonstrated promising efficacy in Asian patients with ESCC, with fewer treatment-related adverse events than chemotherapy. PD-L1 CPS ≥1 is an appropriate cut-off and a predictive marker of pembrolizumab efficacy in Asian patients with ESCC.