Extraprimary Local Recurrence of Esthesioneuroblastoma: Case Series and Literature Review.

Abstract Objectives Esthesioneuroblastoma (ENB) is a rare sinonasal malignancy arising from olfactory neuroepithelium. Recurrence typically occurs locoregionally at the primary site or in the form of cervical metastasis. Delayed local recurrence away from the initial primary site is exceedingly rare. Methods Retrospective review of four patients with histologically confirmed extraprimary local recurrence of ENB was performed with review of the literature. Case Series All cases initially presented with ENB isolated to the cribriform plate(s) treated with primary surgical resection and adjuvant radiotherapy. The first patient had ENB recurrence 8 years post-treatment involving the right orbit. She later developed metastases to the spine, neck, and mandible requiring composite resection and four courses of radiotherapy. The second patient had ENB recurrence of the dorsal septum 9 years post-treatment with cervical metastases requiring septectomy, bilateral neck dissection, and radiotherapy. The third patient had ENB recurrence 7 years post-treatment in the posterior nasopharynx requiring endonasal nasopharyngectomy. Lastly, the fourth patient had ENB recurrence 12 years post-treatment in the sphenopalatine foramen which was endoscopically resected. At the time of this review, all four patients were disease free at 32-months, 21-months, 4-months, and 24-months post-treatment follow-ups, respectively. Conclusion This case series describes the rare phenomenon of delayed extraprimary local recurrence of histologically confirmed ENB. Treatment of extraprimary recurrences, analogous to other forms of ENB, should include primary surgical resection with adjuvant radiotherapy for generally favorable outcomes. Long term close follow-up based on symptoms, endoscopy, and imaging is essential due to the risk of delayed recurrence.