Combination of Capecitabine and Oxaliplatin in Metastatic Nasopharyngeal Carcinoma

Primary: * To evaluate the efficacy of capecitabine in combination with oxaliplatin (XELOX) in terms of overall response rate (based on RECIST criteria) in patients with metastatic NPC without prior chemotherapy for relapse. Secondary: * To evaluate the efficacy profile of oxaliplatin (XELOX) in patients with metastatic NPC in terms of time to progression of disease, survival time, duration of response and complete response rate. * To study the safety and tolerability of the regimen in patients with metastatic NPC.