Cetuximab for the treatment of locally advanced and recurrent/metastatic oral cancer: An investigation of distant metastasis

The aim of this retrospective study was to assess the efficacy and safety of cetuximab therapy for patients with locally advanced (LA) and recurrent.metastatic (R.M) oral squamous cell carcinoma (OSCC), with a specific focus on distant metastases (DMs). Data from 21 patients with unresectable LA and R.M OSCC treated with cetuximab therapy in our department between December, 2012 and July, 2015 were reviewed. The endpoint was the time-to-progression and the assessments made were tumor response rate, progression-free survival (PFS), overall survival (OS) and safety. The overall response rate was 57.1%, with a complete response (CR) rate of 33.3%. The overall median PFS and OS were 5.5 and 8.0 months, respectively. For patients with DMs, the overall response rate was 60.0%, with a CR rate of 40.0%. The median PFS and OS were 3.8 and 5.8 months, respectively. In addition, improved 1-year OS was observed following approval of cetuximab, although the differences between the group of patients treated after that time and historical controls were not statistically significantly (P= 0.246). Grade 3-4 adverse events included infusion reaction (4 cases), neutropenia, hypophosphatemia, upper gastrointestinal hemorrhage, liver toxicity and mucositis (1 case each). There was one cetuximab-related death due to interstitial pneumonia. An acne-like rash was observed in all cases, but no grade 3 or 4 rash was reported. Hypomagnesemia was observed in 10 cases. Our results suggest that cetuximab may display significant therapeutic efficacy in patients with unresectable LA and R.M OSCC, including those with DMs.