Disease stabilization of progressive olfactory neuroblastoma (esthesioneuroblastoma) under treatment with sunitinib mesylate.

Olfactory neuroblastoma (esthesioneuroblastoma) is a rare neoplasm of the olfactory epithelium in the upper nasal cavity. Here, we report the case of a 69-year-old man who presented with massive progression of a metastatic esthesioneuroblastoma after endonasal resection, functional neck dissection, and radiotherapy of local and distant tumor relapses. After exhaustion of all conventional therapeutic options, we initiated treatment with the oral multityrosinekinase inhibitor sunitinib mesylate. Using this drug, significant improvement of clinical symptoms, disease stabilization, and recovery from Karnofsky index of 40% to 70% could be achieved in the absence of significant adverse drug effects. The patient died 15 months after initiation of sunitinib therapy due to complications of a traumatic femoral neck fracture without evidence of tumor progression. Immunohistochemical analysis of tumor tissue specimens obtained at initial surgery revealed ample expression of platelet-derived growth factor receptor (PDGFR)-b on stromal and endothelial cells. Sunitinib should be considered for palliative therapy of advanced esthesioneuroblastoma.