ABSTRACT
PURPOSE: Induction cisplatin and gemcitabine chemotherapy is a standard treatment for locally advanced nasopharyngeal carcinoma (NPC). Inhibition of VEGF axis has been shown to promote maturation of microvasculature and improve perfusion. We conducted a four-arm study to assess the effect of two doses of either sunitinib or bevacizumab with chemotherapy in NPC. PATIENTS AND METHODS: Patients with treatment-naïve locally advanced NPC were treated with three cycles of 3-weekly cisplatin and gemcitabine preceded by 1 week of anti-VEGF therapy for each cycle, followed by standard concurrent chemoradiation: arm A patients received 7 days of 12.5 mg/day sunitinib; arm B 7 days of 25 mg/day sunitinib; arm C bevacizumab 7.5 mg/kg infusion; arm D bevacizumab 2.5 mg/kg infusion. Patients with metastatic NPC were treated with up to six cycles of similar treatment without concurrent chemoradiation. RESULTS: Complete metabolic response (mCR) by whole body 18FDG PET was highest in arm C (significant difference in four groups Fisher exact test P = 0.001; type 1 error = 0.05), with 42% mCR (95% confidence interval, 18-67) and 3-year relapse-free survival of 88% in patients with locally advanced NPC. Significant increase in pericyte coverage signifying microvascular maturation and increased immune cell infiltration was observed in posttreatment tumor biopsies in Arm C. Myelosuppression was more profound in sunitinib containing arms, and tolerability was established in arm C where hypertension was the most significant toxicity. CONCLUSIONS: Bevacizumab 7.5 mg/kg with cisplatin and gemcitabine was well tolerated. Promising tumor response was observed and supported mechanistically by positive effects on tumor perfusion and immune cell trafficking into the tumor.
