Feasibility of Cisplatin/5-Fluorouracil and Panitumumab in Japanese Patients with Squamous Cell Carcinoma of the Head and Neck

OBJECTIVE In Japan, cisplatin/5-fluorouracil 80/800 (cisplatin 80 mg/m2, 5-fluorouracil 800 mg/m2) is widely used to treat recurrent/metastatic squamous cell carcinoma of the head and neck, whereas cisplatin/5-fluorouracil 100/1000 (1000 mg/m2/24 h by continuous intravenous infusion on Days 1-4 plus cisplatin 100 mg/m2 on Day 1 in 3-week cycles) is the standard treatment in Europe and North America. METHODS We prospectively evaluated the feasibility of cisplatin/5-fluorouracil 100/1000 in Japanese patients enrolled in the global Phase 3 study of panitumumab 9 mg/kg combined with cisplatin/5-fluorouracil 100/1000 (Arm 1) versus cisplatin/5-fluorouracil 100/1000 alone (Arm 2). RESULTS Twenty Japanese patients were enrolled and received treatment (Arm 1, n=13; Arm 2, n=7). Grade 3/4 adverse events included neutropenia, hypomagnesemia, stomatitis, hyponatremia, paronychia, febrile neutropenia, decreased appetite and hypokalemia. There were no fatal adverse events. Median overall survival was not estimable in Arm 1 and 15.4 months in Arm 2. Median progression-free survival was 6.9 months in Arm 1 and 5.7 months in Arm 2. The median number of infusions (cycles) of cisplatin was 5 in Arm 1 and 4 in Arm 2; the median number of infusions (cycles) of 5-fluorouracil was 6 in both arms. The mean administered dose for cisplatin was 93.6 mg/m2 in Arm 1 and 97.2 mg/m2 in Arm 2, and 3732.6 and 3880 mg/m2 in Arm 1 and Arm 2, respectively, for 5-fluorouracil. CONCLUSIONS These results suggested that cisplatin/5-fluorouracil 100/1000 was feasible for recurrent/metastatic squamous cell carcinoma of the head and neck in Japanese patients.