Long-Term Outcomes of Management of Olfactory Neuroblastoma: MD Anderson Experience

Background Olfactory neuroblastoma (ONB) is a rare malignant neoplasm of the sinonasal cavity that arises from the superior portion of the nasal vault. This study aims to evaluate the long-term outcomes of patients with olfactory neuroblastoma in our institute, and to determine the factors associated with improved survival and prognosis.

Methods A retrospective review of the medical records of 139 patients treated in MD Anderson Cancer Center for olfactory neuroblastoma between 1992 and 2016. Descriptive statistics were utilized, and Kaplan–Meier curve was utilized to assess survival.

Results Median follow-up time was 75 months (1–445). The tumor epicenter was in the nasal cavity in 86 patients (65%), ethmoid sinus in 39 (29%), maxillary sinus in 5 (3.8%), sphenoid sinus in 1 (0.75%), nasopharynx in 1 (0.75%), and intracranial in 1 (0.75%). Of those patients, 70% were presented with either T3 or T4 disease. Modified Kadish staging was A in 9 (7.5%), B in 31 (25.8%), C in 63 (52.5%), and D in 17 (14.2%). Of those patients, 17 (12.7%) had cervical lymphadenopathy at the time of presentation. Skull base was invaded by the tumor in 78 patients (65.6%) with 66 (56%) having intracranial involvement. Overall 128 patients (92%) had surgery done as a part of their treatment with 93 (73%) receiving postoperative radiation (RT) or chemoradiation (CRT). Median overall survival time in those who received postoperative RT or CRT was 217 months compared with 140 months in those who did not (p = 0.48). Endoscopic approaches were utilized for 72 patients and 79.4% of them had pure endoscopic endonasal approach. Five-year overall survival (OS) and disease-specific survival (DSS) were 85.6 and 93.4%, respectively. Ten-year OS and DSS rates were 51.5 and 77%, respectively. Among 25 patients who received elective nodal irradiation (ENI), 2 patients (8%) developed regional recurrence while 18 patients out of 50 (36%) developed neck recurrence in whom ENI was omitted (p = 0.01). Advanced Kadish stage and presence of cervical lymphadenopathy at the time of presentation were significantly associated with lower survival outcomes. Recurrence rate was 39.6% (55 patients) with median time to recurrence 42 months.

Conclusion Olfactory neuroblastoma has an excellent survival outcome. Surgical resection with or without postoperative radiotherapy is the mainstay of treatment. Endoscopic approaches either pure endoscopic or endoscopic assisted provide a good tool for olfactory neuroblastoma. ENI decreases the risk of nodal recurrence among patients with clinically N0 neck. Despite the excellent survival results, recurrence rate remain high and necessity a long-term surveillance.