960P A real-world clinical outcomes and prognostic factors in Japanese patients with recurrent or metastatic squamous cell carcinoma of head and neck treated with chemotherapy plus cetuximab: A prospective observation study (JROSG12-2)

Abstract

Cetuximab (Cmab), an anti-EGFR monoclonal antibody, was approved for the treatment of recurrent or metastatic squamous cell carcinoma of head and neck (RM-SCCHN). Cmab has been combined not just with platinum-based chemotherapy, but also with other chemotherapy regimens. The aims of this study are to evaluate the clinical outcomes and safety of first-line treatment with chemotherapy plus Cmab in the real-world patients with RM-SCCHN and to identify prognostic factors for overall survival (OS). This is a prospective observation study involving 20 oncology institutions in Japan. All consecutive patients with RM-SCCHN treated with a first-line therapy consisting of any chemotherapy regimens plus Cmab between December 2013 and February 2017 were included. The primary objective of the study was 1-year OS. Secondary objectives included response rate and adverse events. This work is supported by Merck Biopharma. Of 120 patients recruited, 114 patients were analyzed. Patients characteristics were as follows: median age, 64 years; PS0/1/2, 48.2%/49.1%/2.6%; primary tumor sites, hypopharynx/oral cavity/oropharynx/larynx, 34.2%/27.2%/25.4%/13.2%; combined chemotherapy, FP/FU+CBDCA/PTX/S-1, 52.6%/22.8%/14.9%/5.3%. Of 78 patients who achieved disease control, 31 patients continued Cmab monotherapy as maintenance. The median OS was 1.0 year (95% confidence interval [CI] 0.8-1.2). A point estimate of 1-year survival rate was 51.1%. On multivariate analysis, independent unfavorable prognostic factors for OS were performance status ≥1, primary tumor site (oral cavity), nodal staging (≥2), presence of distant metastasis, no salvage chemotherapy, and lack of objective response. Overall response rate was 26.3% (95%CI 18.5 - 35.4). Grade 3 and 4 adverse events included neutropenia (22.8%), hypokalemia (9.6%), rash acneiform (7.0%), pneumonitis (1.8%), and infusion related reaction (0.9%). Combination of chemotherapy and Cmab showed promising signs of efficacy and tolerability in patients with RM-SCCHN in the real-world. Several prognostic factors were identified for OS.