Dramatic response to targeted therapy in an aggressive olfactory neuroblastoma: illustrative case

BACKGROUND: Olfactory neuroblastomas are rare sinonasal tumors that arise from the olfactory epithelium. The authors presented a case of an olfactory neuroblastoma with extensive cranial invasion that demonstrated dramatic response to sorafenib, a tyrosine kinase inhibitor. OBSERVATIONS: A 54-year-old man with history of prostate cancer and melanoma presented with left-sided proptosis and was found to have a 6.5-cm Kadish stage D olfactory neuroblastoma with cranial invasion that was refractory to chemotherapy and everolimus. However, it demonstrated dramatic response to sorafenib, causing extensive skull base defects that prompted operative repair. Genomic analysis of the tumor revealed mutations in TSC1 and SUFU. The patient developed disease progression with liver metastases 35 months after starting sorafenib, prompting a change to lenvatinib. He experienced progression of his olfactory neuroblastoma 10 months following this change and died in hospice 1 month later. LESSONS: The authors reviewed the clinical presentation and management of a large olfactory neuroblastoma with dramatic response to sorafenib. They highlighted prior uses of targeted therapy in the management of refractory olfactory neuroblastoma within the context of current standard treatment regimens. Targeted therapies may play a vital role in the management of refractory olfactory neuroblastoma.