Bleeding complications and possible resistance patterns of anti-angiogenesis treatments in recurrent/metastatic head-and-neck squamous cell carcinoma – Reflections from a phase II study of pazopanib in recurrent/metastatic head-and-neck squamous cell carcinoma

Background: Due to smoking, alcohol, and betel nut use, head-and-neck squamous cell carcinoma (HNSCC) is a serious public health problem in Taiwan. Materials and Methods: We performed a single-arm Phase II trial of pazopanib in patients with platinum-refractory recurrent or metastatic HNSCC in 2011. Results: We screened 43 patients in about 6 months. Thirty-three of the patients were excluded due to easy bleeding and vessel contact resulting from the advanced tumor status. The remaining ten patients were included in this study. An objective response was seen in one patient; six patients had clinical benefits, which was comparable with the outcomes of sorafenib or sunitinib in this patient group. Four patients experienced at least Grade 3 bleeding. The tumor response was usually seen in the central cavity; the rim of the cavity extended outside, reflecting peripheral invasion and future resistance. Conclusion: The early use of anti-angiogenesis treatments is necessary for better tumor control and to prevent bleeding and potential resistance. In future, vascular endothelial growth factor receptor and/or epidermal growth factor receptor tyrosine kinase inhibitors may be used in combination with immunotherapy to increase the clinical benefits and avoid the risk of hyperprogression.