Esthesioneuroblastoma: Summary of Single-center Experiences with Focus on Adjuvant Therapy and Overall Survival

Esthesioneuroblastoma (ENB) is a rare malignant tumor of the nasal cavity. The genetic basis of its development is still under study and has not been fully delineated. It has varying symptoms depending on the lesion's location within the nasal cavity. The most commonly used systems for such lesions are the Kadish staging and Haymes grading systems. The objectives are to review the most recent published literature evaluating the different treatments/ combination of treatment and assess the most appropriate treatment modality that can provide the longest progression-free survival and overall survival for ENB patients. Moreover, a look at what the latest literature suggests when it comes to adjuvant treatments and their effect on survival is also key to further the body of knowledge for neurosurgeons, Ears, Nose, and Throat (ENT) physicians and all the different subspecialties that deal and serve these population of patients. The published literature was reviewed starting from 1990. The focus was made on single-center experiences given their availability and easy access. The most recently published systematic review was used as the benchmark; research published after that was included in this study. The database search in OVID was conducted using the following keywords: "Esthesioneuroblastoma", "ENB", "Olfactory Neuroblastoma", Nose neoplasm", skull base neoplasm", "radiation", and "resection". The database search found 17 papers which included 14 single-center reports, one systematic review, and two nationwide multi-center reviews. Surgery plus adjuvant radiation therapy appears to provide the best overall survival and progression-free survival especially in patients with high Kadesh grade. On the other hand, surgery alone or biopsy followed with radiation therapy provided the lower progression-free survival and overall survival from time of diagnosis. The role of chemotherapy, however, requires further investigation to assess its potentially harmful effects. The use of surgery as a stand-alone modality of treatment should be cautiously and rarely used in patients with lower staging scores and multiple negative resection margins.