Feasibility of cetuximab and chemoradiotherapy combination in Chinese patients with unresectable stage III non-small cell lung cancer: a preliminary report.

Abstract

In recent years, the combination of cetuximab and chemoradiotherapy (CRT) has been used to treat stage III non-small cell lung cancer (NSCLC); however, limited data are available for Chinese patients. Herein, we report preliminary data from a phase I/II study testing the combination of cetuximab with inductive chemotherapy, followed by concurrent CRT (CCRT) in Chinese patients with stage III NSCLC. Eligibility criteria were Zubrod performance status (PS) 0-1, forced expiratory volume in 1 second (FEV1) ≥1.2 L and adequate organ function. Enrolled patients received weekly cetuximab (initial dose of 400 mg/m(2) on day 1 of week 1 and a maintenance dose of 250 mg/m(2) on week 2 to the end of CCRT) with cisplatin/vinorelbine (NP) chemotherapy (every 3 weeks for 2 cycles from week 2, followed by two cycles of concomitant NP chemotherapy and intensity-modulated thoracic radiotherapy (TRT) (60-66 Gy/2 Gy). The primary endpoints were toxicity and feasibility. All patients received positron emission tomography-computerized tomography (PET-CT) scans within the 2 weeks prior to enrollment. Univariate analyses were used to assess the correlation between SUV-T, SUV-N, SUV-TOTAL, gender, age, histology, tumor-node-metastasis (TNM) stage, PS and smoking status and survival. Survival curves were generated for different populations using the Kaplan-Meier method and compared using a log-rank test. Seventeen patients were enrolled and 16 completed the full regime. The overall response rate (ORR) was 58.8% and 82.3% after the induction and CCRT phases, respectively. With a median follow-up duration of 27.6 months, the median survival was 27.6 months [95% confidence interval (CI): 11.3-43.9 months] with 1- and 2-year survival rates of 88.2% (95% CI, 60.6-96.9%) and 58.8% (95% CI, 60.6-77.8%), respectively. Three patients remain progression-free to date, and the median progression-free survival (PFS) was 13.5 months (95% CI, 6.8-20.2 months). No treatment-related death occurred; however, 76% of the patients experienced grade 3+ adverse events (AEs), including nausea/vomiting, intestinal obstruction, and esophagitis (<6%), while other AEs were mostly of hematological nature (71%). The cut-off values for SUV-T and SUV-TOTAL were 11 and 20, respectively. Univariate analyses revealed SUV-TOTAL (P=0.027), SUV-T (P=0.025), and PS (P=0.006) as potential survival predictors, with a hazard ratio (HR) of 3.4, 3.7, and 9.9, respectively. The combination of cetuximab with induction chemotherapy followed by CCRT appears feasible and promising. Local and locoregional maximal SUVs, defined by (18)F-FDG PET-CT scanning, may represent a prognostic indicator for long-term survival for these patients, which warrants further study.