Long-Term Outcomes of Olfactory Neuroblastoma: MD Anderson Cancer Center Experience and Review of the Literature.

OBJECTIVES/HYPOTHESIS: Olfactory neuroblastoma (ONB) is a rare sinonasal malignant neoplasm that is known to develop late recurrence. The aim of this study is to evaluate the long-term outcomes of patients with ONB and to determine the factors associated with prognosis.

STUDY DESIGN: Retrospective study.

METHODS: A retrospective review of the medical records of 139 patients diagnosed with ONB at MD Anderson Cancer Center was performed between 1991 and 2016. Descriptive statistics were calculated, and Kaplan-Meier curves were utilized to assess survival.

RESULTS: Median follow-up time was 75 months. Overall, 129 patients (92.8%) had surgery as part of their treatment and 82 (58.9%) patients received postoperative radiation therapy (PORT) or concurrent chemoradiotherapy. Endoscopic approaches were utilized for 72 patients, 69.4% of whom had pure endoscopic endonasal approaches. Five-year overall survival and disease-specific survival were 85.6% and 93.4%, respectively. Recurrence rate was 39.6% with a median time to recurrence of 42 months. Among the 31 patients who received elective nodal irradiation (ENI), two patients developed neck recurrence (6.4%) compared with 20 who developed neck recurrence when ENI was omitted (34.4%) (P = .003). Advanced Kadish stage, orbital invasion, intracranial invasion, and presence of cervical lymphadenopathy at the time of presentation were significantly associated with poor survival.

CONCLUSION: ONB has an excellent survival. Surgical resection with PORT when indicated is the mainstay of treatment. Endoscopic approaches can be used as a good tool. Elective neck irradiation reduces the risk of nodal recurrence among patients with clinically N0 neck. Despite the excellent survival, recurrence rate remains high and delayed, highlighting the need for long-term surveillance.

LEVEL OF EVIDENCE: Level 4 Laryngoscope, 2021.