Unexpectedly durable palliation of metastatic olfactory neuroblastoma using anti-angiogenic therapy with Bevacizumab

Olfactory neuroblastomas (ONBs) are rare malignant tumors that arise from olfactory epithelium and typically present with symptoms attributable to locally invasive disease. Kadish radiographic staging and Hyams' histopathologic grading are prognostic. Overall survival rates, averaging 60-70% at 5 years, remain limited by high rates of delayed loco-regional and distant progression. At initial presentation, the available evidence supports the use of multimodality therapy, historically surgery and radiation, to improve disease-free and overall survival. At recurrence/progression, the available evidence supports the use of therapy to improve disease control and symptoms (palliation), but patient heterogeneity dictates individualization of modalities. Although the ideal use of chemotherapy as a modality remains undefined, the available evidence supports it use, historically platinum-based, for palliation. However, recent insights into the molecular-genetic aberrations of ONBs, coupled with the emergence chemotherapeutic agents capable of targeting such aberrations, suggest an expanded role. The authors report a case of a 60 years-old man, heavily pre-treated for metastatic ONB, presenting with profound central-nerve-system and head-and-neck symptoms. He experienced unexpectedly durable palliation with Bevacizumab anti-angiogenic therapy. Additionally, he experienced localized palliation with an Ommaya reservoir. The authors review the literature regarding historical and emerging therapies for ONB to emphasize the needs for individualization and translational-clinical studies.