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Page 8 of 15 Okafor et al. Mini-invasive Surg 2024;8:28 https://dx.doi.org/10.20517/2574-1225.2023.128

resection and postoperative radiation therapy is the mainstay of treatment for advance stage disease whereas
those with low-stage disease are typically treated with surgical resection followed by radiation therapy [94-96] .
More prospective trials with larger patient cohorts should be included to further elucidate established
treatment protocols for pediatric patients.

MANAGEMENT OF THE NECK
Elective management for cN0 neck in olfactory neuroblastoma is debatable, with varying viewpoints and
limited evidence [26,97-99] . Some studies advocate for prophylactic neck treatment in the high-risk group of
patients who have high-grade tumors or advanced Kadish stages (B and C) [99,100] . Due to the low incidence of
nodal metastasis at the time of presentation and co-morbidities associated with radiation treatment, other
investigations suggest conservative management with neck surveillance [26,97,98,101,102] . When patients present
with late cervical lymph node metastasis, a multimodality approach consisting of neck dissection and
[102]
adjuvant radiation illustrated better disease-free survival compared to single modality survival outcomes .
Positive cervical lymph node metastasis is considered a known predictor of survival in olfactory
neuroblastoma [4,8,83,103] . Overall incidence of nodal metastasis is around 30% of cases, with 5%-8% of patients
presenting with nodal metastasis at the time of diagnosis [4,97,102] . The most common lymph nodes affected are
level II cervical lymph nodes (90% of cases), followed by levels I/III lymph nodes (50%) and retropharyngeal
[97]
lymph nodes (40%). Levels IV and V nodal metastasis were reported in high-grade advanced tumors .
When addressing cervical metastasis, general consensus recommends a proactive approach with neck
[4]
dissection followed by adjuvant radiation . However, the extent of neck dissection required remains
unclear. Selective neck dissection with further surveillance of the nodal drainage pattern has been
suggested [97,104] .

PROGNOSIS, LONG-TERM OUTCOMES, AND SURVEILLANCE
Outcome studies have identified several factors associated with better prognosis, which include patients
aged 60 or less, female gender, lower histological tumor grade, lower Kadish stage, negative neck metastasis,
and achieving total resection with negative margins. These factors collectively contribute to improved
survival and treatment outcomes [82,105,106] . In contrast, male patients often present with advanced- and high-
grade tumors . These findings provide valuable insights into identifying high-risk patients and assist in
[106]
determining the need for adjuvant treatments.

Rimmer et al. conducted a comprehensive meta-analysis consisting of 95 patients with olfactory
neuroblastoma who were treated and followed over a 35-year period showing a 5-year overall survival rate
of 83.4% and a 10-year overall survival rate of 76.1% [9,66] . Disease-free survival rates at five and ten years were
80% and 62.8% respectively, with a mean follow-up period around seven years . Local recurrence occurred
[9]
in 25.3% of patients, with an average recurrence time of around five years. Of these cases, 25% of patients
exhibited early recurrence within a year. Late recurrence was reported in 33% of the cases after five years,
and 8% after ten years of diagnosis and treatment [9,66] . These findings highlight the importance of long-term
surveillance.

Detecting and addressing tumor recurrence extended patient survival by an average of 29 months in those
who eventually died and an average of 93 months in patients who were still living by the conclusion of the
Rimmer study. In this same investigation, surgical approaches were evaluated. Sixty-five patients underwent
craniofacial resection while 30 patients had endoscopic resection. Further analysis of the surgical techniques
demonstrated significantly improved overall survival and disease-free survival rates in those who underwent
endoscopic resection in comparison to those of the craniofacial resection group. Advanced-stage tumor