Treatment of unilateral olfactory neuroblastoma: Appropriate extent of surgical resection and potential for olfactory preservation

Historically, comprehensive surgical resection for olfactory neuroblastoma has included the bilateral olfactory epithelium, cribriform plate, overlying dura, olfactory bulbs and tracts. This results in postoperative anosmia that may significantly impact a patient's quality of life without definitive added benefit in survival. The prevalence of occult intracranial disease is low, especially for Hyams grade I and II tumors. A unilateral approach sparing the contralateral cribriform plate and olfactory system can be considered for select cases of early stage, low-grade tumors when the disease does not cross midline to involve the contralateral olfactory cleft or septal mucosa and when midline dural margins can be cleared with frozen pathology. Approximately half of patients who undergo unilateral resection may have residual olfaction even with adjuvant unilateral radiation. Early data suggest favorable disease-free survival and overall survival for patients who underwent the unilateral approach; however, larger sample studies are needed to confirm comparability to bilateral resections regarding oncologic outcomes.

Ectopic Olfactory Neuroblastoma: Systematic Review of a Rare Clinical Entity among Sinonasal Tumors

Objectives  Ectopic olfactory neuroblastoma is an uncommon manifestation of an already rare neoplasm. We aimed to systematically review the literature for cases of ectopic olfactory neuroblastoma to better characterize this rare disease entity and to present two new case reports. Methods  A search of the PubMed and Embase databases was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify English-language articles reporting cases of ectopic olfactory neuroblastoma, published from 1955 through November 2021. Results  Sixty-six cases of ectopic olfactory neuroblastoma were identified in 62 articles including the current review. Ectopic olfactory neuroblastoma arose in a wide age range (2-89 years) without significant sex predilection. It occurred most commonly in the ethmoid (25%), maxillary (25%), and sphenoid (16%) sinuses. Seventy-three percent of cases presented with low Hyams grade (I and II). The most common symptoms were nasal obstruction (32%) and epistaxis (32%). Paraneoplastic syndromes were observed in 27% of patients. The most common treatment was surgical resection followed by adjuvant radiotherapy. Overall, 76% of all patients were disease-free at the time of last follow-up. Locoregional recurrences and distant metastases were found in 19 and 5% of cases, respectively. Conclusion  This systematic review describes previously reported cases of ectopic olfactory neuroblastoma, a disease entity with poorly understood characteristics. Physicians should consider olfactory neuroblastoma in the differential diagnosis for sinonasal masses, as their ectopic presentation may present considerable diagnostic and therapeutic difficulties. Patients with olfactory neuroblastoma may benefit from long-term follow-up and routine endoscopic examinations for surveillance of ectopic recurrences.

Review of neoplasia in fish at a large display aquarium, 2005-2021

Fish maintained in managed care may have longer lifespans as a result of advances in veterinary medicine and husbandry and reduced risk of predation. Neoplasia is of increasing interest in managed aquarium populations. However, few studies have systematically evaluated neoplasia in managed fish populations. Our objective in this retrospective study was to review and describe neoplasia diagnosed in fish at a large public display aquarium between 2005 and 2021. Any fish diagnosed with neoplasia on either antemortem or postmortem evaluation during the study period was included, and all medical records, biopsy, and autopsy reports were reviewed. Sixty-two fish met the inclusion criteria; 37 species were included in the study population, most of which were tropical freshwater fish (n = 34 fish). Thirty-two types of neoplasia were identified. Ten fish had benign neoplasms, and 53 fish had malignant neoplasms. The most common neoplasms were of epithelial and neuroectodermal origin. The most common site of tumor origin was the skin. Our data suggest that mesenchymal neoplasms may be more common in cold saltwater fish than in tropical freshwater and saltwater fish. Malignant neoplasms were most commonly diagnosed in the study population and should be a top differential when neoplasms are identified in fish managed under human care. Our study contributes to the overall knowledge of the health of aquarium fish and may aid clinicians in characterizing neoplasia that may be present in fish under human care.

Patterns of recurrence and disease progression in patients with positive-margin olfactory neuroblastoma following primary resection

OBJECTIVE

Olfactory neuroblastoma (ONB) is a rare, malignant tumor of the sinonasal tract that arises from olfactory epithelium. Although surgery is the preferred first-line treatment, tumor involvement of adjacent structures may preclude the ability to achieve negative margins during initial resection. Herein, the authors examine the oncological outcomes of patients with positive margins after primary resection of ONB, with the aim of determining predictors of disease progression and patterns of recurrence.

METHODS

The authors performed an institutional review of 25 patients with positive-margin ONB after resection. Cox survival analyses were used to determine any statistically significant predictors of worse progression-free survival (PFS) and overall survival (OS).

RESULTS

A total of 93 patients who were diagnosed with ONB were identified, of whom 25 patients had positive margins following their primary resection. Eleven (44%) had a delayed finding of positive margins that were initially negative in the operating room but returned as positive on final pathology. Four patients had subtotal resection (STR), whereas the remaining patients underwent gross-total resection. Twenty-four patients received adjuvant radiotherapy (96%), and 15 additionally received adjuvant chemotherapy (60%). Fourteen patients (56%) experienced recurrence/progression at a median time of 35 months following resection (IQR 19-70 months). Local recurrence occurred in 10 patients (40%), regional in 9 (36%), and distant metastasis in 2 (8%). In Cox survival analyses, the 5-year PFS and OS were 55.1% and 79.2%, respectively. Kadish stage D was predictive of worse PFS in univariate (hazard ratio [HR] 15.67, 95% CI 3.38-72.61, p < 0.001) and multivariate (HR 15.46, 95% CI 1.45-164.91, p = 0.023) analyses. Hyams grade, adjuvant chemotherapy, and primary radiotherapy were not associated with PFS. Furthermore, Kadish stage D and STR were predictive of worse OS in univariate analysis (HR 12.64, 95% CI 2.03-78.86, p = 0.007; HR 7.31, 95% CI 1.45-36.84, p = 0.016; respectively). However, local and regional recurrence was not associated with worse OS.

CONCLUSIONS

Approximately half of patients with positive-margin ONB may experience disease recurrence. Patients with an advanced disease stage (Kadish D) may have a higher likelihood of developing recurrence/progression. Furthermore, patients with tumor burden following resection (STR and Kadish D) may have worse OS. However, in positive-margin ONB with no gross disease following initial resection, the presence of disease recurrence does not significantly alter survival when receiving salvage therapy.

SNOT-22 subdomain outcomes following treatment for sinonasal malignancy: A prospective, multicenter study

BACKGROUND

Patients with sinonasal malignancy (SNM) present with significant sinonasal quality of life (QOL) impairment. Global sinonasal QOL as measured by the 22-item Sinonasal Outcomes Test (SNOT-22) has been shown to improve with treatment. This study aims to characterize SNOT-22 subdomain outcomes in SNM.

METHODS

Patients diagnosed with SNM were prospectively enrolled in a multi-center patient registry. SNOT-22 scores were collected at the time of diagnosis and through the post-treatment period for up to 5 years. Multivariable regression analysis was used to identify drivers of variation in SNOT-22 subdomains.

RESULTS

Note that 234 patients were reviewed, with a mean follow-up of 22 months (3 months-64 months). Rhinologic, psychological, and sleep subdomains significantly improved versus baseline (all p < 0.05). Subanalysis of 40 patients with follow-up at all timepoints showed statistically significant improvement in rhinologic, extra-nasal, psychological, and sleep subdomains, with minimal clinically important difference met between 2 and 5 years in sleep and psychological subdomains. Adjuvant chemoradiation was associated with worse outcomes in rhinologic (adjusted odds ratio (5.22 [1.69-8.66])), extra-nasal (2.21 [0.22-4.17]) and ear/facial (5.53 [2.10-8.91]) subdomains. Pterygopalatine fossa involvement was associated with worse outcomes in rhinologic (3.22 [0.54-5.93]) and ear/facial (2.97 [0.32-5.65]) subdomains. Positive margins (5.74 [2.17-9.29]) and surgical approach-combined versus endoscopic (3.41 [0.78-6.05])-were associated with worse psychological outcomes. Adjuvant radiation (2.28 [0.18-4.40]) was associated with worse sleep outcomes.

CONCLUSIONS

Sinonasal QOL improvements associated with treatment of SNM are driven by rhinologic, extra-nasal, psychological, and sleep subdomains.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Simple and safe resection of the crista galli

A critical procedure in the transcribriform approach is the resection of the crista galli. However, the standard technique for crista galli resection has several disadvantages. We reviewed the cases of patients with olfactory neuroblastomas who underwent an endoscopic endonasal transcribriform approach using a newly developed technique for crista galli resection. We performed a cadaveric study to measure the superior accessibility limits using the proposed method. We included 38 patients with olfactory neuroblastomas in this study. The tumor invaded the posterior crista galli in four patients. The anterior end of the crista galli was not invaded by the tumor. Our cadaveric study showed that the dura was approachable to the point that was 7.4 ± 1.3 mm superior and 23.2 ± 7.2 mm lateral to the foramen cecum following crista galli removal. By resecting the crista galli in advance, manipulation of the superior dura became feasible.

Outcomes following proton therapy for pediatric esthesioneuroblastoma

BACKGROUND

Pediatric esthesioneuroblastoma (EN) can infiltrate skull base anatomy, presenting challenges due to high radiation doses and pediatric tissue sensitivity. This study reports outcomes of pediatric EN treated with proton radiotherapy (PT).

PROCEDURE

Using an IRB-approved prospective outcomes registry, we evaluated patient, tumor, and treatment-related variables impacting disease control and toxicity in pediatric nonmetastatic EN treated with modern multimodality therapy, including PT.

RESULTS

Fifteen consecutive patients (median age 16) comprising Kadish stage B (n = 2), C (n = 9), and D (n = 4) tumors were assessed, including six with intracranial involvement, four with cranial nerve deficits, and four with cervical lymphadenopathy. Before radiation, two had subtotal and 13 had gross total resections (endoscopic or craniofacial). Two underwent neck dissection. Eleven received chemotherapy before radiation (n = 5), concurrent with radiation (n = 4), or both (n = 2). Median total radiation dose (primary site) was 66 Gy/CGE for gross disease and 54 Gy/CGE (cobalt Gray equivalent) for microscopic disease. Median follow-up was 4.8 years. No patients were lost to follow-up. Five-year disease-free and overall survival rates were 86% (no local or regional recurrences). Two patients developed vertebral metastases and died. Two required a temporary feeding tube for oral mucositis/dysphagia. Late toxicities included symptomatic retinopathy, major reconstructive surgery, cataracts, chronic otitis media, chronic keratoconjunctivitis, hypothyroidism, and in-field basal cell skin cancer.

CONCLUSIONS

A multimodality approach for pediatric EN results in excellent local control. Despite the moderate-dose PT, serious radiation toxicity was observed; further dose and target volume reductions may benefit select patients. Longer follow-up and comparative data from modern photon series are necessary to fully characterize any relative PT advantage.

Upright proton therapy for esthesioneuroblastoma: a single-institution experience

Aim

This study presents an analysis (efficacy and toxicity) of outcomes in patients with esthesioneuroblastoma after pencil beam proton therapy with a fixed beamline in the upright position.

Background

Esthesioneuroblastoma (ENB) is an extremely rare tumor of sinonasal area located in critical proximity to vital structures. Proton therapy (PT) is often considered the optimal radiation treatment for head-and-neck tumors, although of limited availability. Upright PT delivered using fixed pencil beamline and rotating chair is a fairly promising option.

Methods

This is a single-center experience describing the outcomes of PT in 14 patients with ENB treated between January 2016 and October 2022; half of the cases had a history of previous irradiation. The therapy was applied using a fixed pencil beamline with 6D-chair for positioning. The median dose was 63 GyRBE (total range 48-70 GyRBE; based on 1.1 RBE multiplier for protons) with 2.0 GyRBE per fraction. The mean gross tumor volume was 109.5 cm3 (17.1-257.7 cm3). Patient demography, pathology, treatment parameters and toxicity data were analyzed. Radiation-induced reactions were assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v 4.0.

Results

The median follow-up time was 28 months. The 1- and 2-year locoregional control rates constituted 100% and 88.9%, respectively; the median duration of local control was 52 months. The 1- and 2-year progression-free survival (PFS) rates constituted 92.9% and 75.0%, respectively; the median PFS duration was 52 months. The 1- and 2-year overall survival (OS) rates constituted 92.9% and 84.4%, respectively. Two patients died of non-cancer-related causes (coronavirus-induced pneumonia) and 1 patient died of tumor progression. All patients tolerated PT well without any treatment gaps. Serious late toxicity reactions included glaucoma in 1 patient and cataract in 2 patients, in over half a year since irradiation.

Conclusion

PT with upright design of the unit affords promising outcomes in terms of disease control and toxicity rates in ENB, a sinonasal tumor of complicated localization.

Rare case of mortality after hemorrhagic property of esthesioneuroblastoma

Esthesioneuroblastoma is a tumor arising from olfactory neuroepithelium with an incidence of four per million. This case presents a rare nasal cavity neoplasm with hemorrhagic properties that may lead to significant sequelae. We present a 69-year-old male patient who presented with worsening altered mental status over the past 6-7 months. His Glasgow coma scale was a nine, showing a large mass centered at the cribriform plate with extension intracranially, sinonasal cavity, and bilateral orbits on diagnostics. Bifrontal craniotomy was performed one day after admission with resection of the tumor in the cranial fossa and intranasally, and decompression of the brainstem, frontal lobes, and third ventricle. After surgery, the patient was managed in the intensive care unit but continued to deteriorate. He was confirmed to have no meaningful brain activity and eventually deceased seven days after admission. Depending on the tumor stage, esthesioneuroblastoma can have a favorable prognosis with proper therapies. Different surgical techniques for ENB lead to the question of which therapeutic modality is the best because of the tumor's gross hemorrhagic properties. With adjunctive radiation therapy and/or chemotherapy, more research can bring light to proper surgical techniques.

Genomic characterization of an esthesioneuroblastoma with spinal metastases: illustrative case

BACKGROUND

Esthesioneuroblastoma (ENB) is a rare neoplasm of the sinonasal tract. Currently, the optimal treatment includes maximal resection combined with radiotherapy and/or chemotherapy. Although ENBs often recur and have an aggressive clinical course, spinal metastases are extremely rare and the underlying molecular mechanisms are poorly understood.

OBSERVATIONS

Here, the authors describe a 50-year-old male with an aggressive ENB, initially treated with resection and chemotherapy/radiation, who developed multiple thoracic and lumbar spinal metastases. The authors performed targeted exome sequencing on both the resected primary tumor and biopsied spinal metastases, which revealed 12 total variants of unknown clinical significance in genes associated with the PI3K/AKT/mTOR pathway, chromatin remodeling, DNA repair, and cell proliferation. Six of these variants were restricted to the metastatic lesion and included missense mutations with predicted functional effects in GRM3, DNMT3B, PLCG2, and SPEN.

LESSONS

This report discusses the potential impact of these variants on tumor progression and metastasis, as well as the implications for identifying potential new biomarkers and therapies.

Olfactory neuroblastoma: diagnosis, management, and current treatment options

Olfactory neuroblastoma (ONB) is a rare neoplasm originating from the olfactory neuroepithelium representing 3-6% of tumors of the sinonasal tract. ONB require multi-disciplinary care. Historically, the gold standard surgical procedure for ONB has been open craniofacial resection. In the last years, endoscopic endonasal approaches have been largely introduced with lower complication rates, shorter hospital stay, and similar clinical outcome. Radiotherapy plays an important role in the management of ONB, however there are not generally accepted recommendations for its application. Although there is agreement that multimodal therapy is needed, the optimal use of chemotherapy is still unknown. The rarity of the disease, makes difficult to draw definitive conclusions about the role of systemic treatment in induction and concomitant setting.

Radiographic predictors of occult intracranial involvement in olfactory neuroblastoma patients

BACKGROUND

Traditional management of olfactory neuroblastoma (ONB) includes margin-negative resection with removal of cribriform plate, dura, and olfactory bulb, regardless of intracranial disease. This approach may be overtreating certain patients. Our investigation examines risk factors associated with occult intracranial disease to optimize therapeutic outcomes.

METHODS

This retrospective, multi-institutional cohort study examined clinical covariates associated with occult intracranial involvement. Patient demographics, staging, Hyam's grade, and pathologic involvement of dura, olfactory bulb/tract, and brain were collected. Diagnostic imaging was reviewed. Positive and negative predictive value (NPV) were estimated along with effect size estimates. Cox hazard regression examined associations with overall survival (OS) and disease-free survival (DFS).

RESULTS

A total of 224 subjects with new diagnoses of ONB (2005-2021) were identified. Skull base bone involvement on computed tomography (CT) had the highest NPV for pathologic dura (88.0%), olfactory bulb (88%), and brain involvement (97.3%). Hyam's grade category was significantly associated with dural involvement (φC  = 0.26; 95% confidence interval [CI]: 0.16, 0.42). Subjects without radiologic skull base involvement (n = 66) had pathologic positivity of 12.1%. Within this subgroup, Hyam's grade was clinically significant for dural positivity (φ = 0.34; 95% CI: -0.12, 0.71) with 28.6% involvement in high grade tumors. Neither clinical nor pathologic positivity of intracranial structures were associated with significantly different OS or DFS.

CONCLUSIONS

Both CT and magnetic resonance imaging (MRI) had reasonably good NPV for involvement of dura and olfactory bulb. Higher Hyam's grade was associated with dural involvement. Patients with low-grade tumors not involving the skull base may be suitable for avoiding skull base resection; however, further investigation is warranted.

Failure Patterns of Recurrence in Patients With Localized Esthesioneuroblastoma Following Surgery and Adjuvant Radiotherapy Without Elective Nodal Irradiation

BACKGROUND

Esthesioneuroblastoma (ENB), a rare malignancy arising from the olfactory epithelium, poses clinical challenges owing to its propensity for local invasion and recurrence. Its management typically involves surgical resection and adjuvant radiotherapy. However, debate persists regarding the optimal treatment strategy, particularly the use of elective nodal irradiation (ENI). This study aimed to investigate recurrence patterns in patients with localized ENB treated with surgery and adjuvant radiotherapy without ENI.

METHODS

Our retrospective analysis included patients who underwent surgery followed by adjuvant radiotherapy for treatment of ENB between January 2011 and November 2022. Patients with incomplete data or who had received neoadjuvant radiotherapy were excluded. Patient characteristics, radiotherapy data (type, dose, and duration), and follow-up data were collected. Recurrence patterns were evaluated, and overall survival (OS), disease-free survival (DFS), and local control rates were determined using the Kaplan-Meier method.

RESULTS

Twelve patients with ENB (median age, 56 years) were included. Most had stage C disease. The median radiation dose was 60 Gy, and the median treatment duration was six weeks. Only one death was confirmed during the observation period, and the five-year DFS rates were 64.3%. Local control was achieved in 11 patients, with only one experiencing local recurrence. Regional lymph node recurrence occurred in three patients and was successfully managed via neck dissection. The timing of recurrence varied, emphasizing the importance of long-term surveillance.

CONCLUSION

Adjuvant radiotherapy without ENI is a viable treatment option for ENB, resulting in favorable local control and OS outcomes. Regional lymph node metastases were observed but effectively managed via salvage therapy. Prospective studies with larger cohorts are warranted to confirm the effectiveness of this treatment strategy and to define optimal radiotherapy fields.

Syndrome of Inappropriate Antidiuretic Hormone Release Secondary to Ectopic Olfactory Neuroblastoma: Case Report and Review of Literature

Ectopic olfactory neuroblastoma (ONB) is a rare neuroendocrine sinonasal malignancy which arises from sinonasal regions where olfactory neuroepithelium does not exist. Presentation of syndrome of inappropriate antidiuretic hormone release (SIADH) in patients with ectopic ONB is extremely rare. We report a case of a 22-year-old patient with ectopic ONB and paraneoplastic SIADH that was managed at our center. The ONB was arising from the left lamina papyracea and extending into the maxillary and ethmoid sinuses and filling the nasal cavity. Correction of sodium levels occurred within 24 hours of endoscopic resection via a combined trans-nasal transorbital approach. To avoid negative sequela secondary to rapid sodium correction, the patient was managed by desmopressin to obtain gradual sodium correction, which was achieved on the fourth postoperative day. Ectopic presentation of ONB with paraneoplastic SIADH is extremely rare with only 7 cases reported in the literature to date. Management via surgical resection and/or radiotherapy for these patients requires the managing clinician to be vigilant of serum sodium levels. A multidisciplinary approach is essential for optimal outcomes.

Stereotactic radiosurgery for distant brain metastases secondary to esthesioneuroblastoma: a single-institution series

OBJECTIVE

Esthesioneuroblastoma (ENB), also known as olfactory neuroblastoma, is a rare, malignant tumor of neuroectodermal origin that arises from the olfactory neuroepithelium. In this study the authors present the first series in the literature on distant brain metastases (BMs) secondary to ENB that were treated with stereotactic radiosurgery (SRS), to evaluate the safety and effectiveness of SRS for this indication.

METHODS

A retrospective analysis of clinical and radiological outcomes of patients with ENB who underwent CyberKnife (CK) SRS at a single center was conducted. The clinical and radiological outcomes of patients, including progression-free survival, overall survival, and local tumor control (LTC) were reported.

RESULTS

Between 2003 and 2022, 32 distant BMs in 8 patients were treated with CK SRS at Stanford University. The median patient age at BM diagnosis was 62 years (range 47-75 years). Among 32 lesions, 2 (6%) had previously been treated with surgery, whereas for all other lesions (30 [94%]), CK SRS was used as their primary treatment modality. The median target volume was 1.5 cm3 (range 0.09-21.54 cm3). CK SRS was delivered by a median marginal dose of 23 Gy (range 15-30 Gy) and a median of 3 fractions (range 1-5 fractions) to a median isodose line of 77% (range 70%-88%). The median biologically effective dose was 48 Gy (range 21-99.9 Gy) and the median follow-up was 30 months (range 3-95 months). The LTC at 1-, 2-, and 3-year follow-up was 86%, 65%, and 50%, respectively. The median progression-free survival and overall survival were 29 months (range 11-79 months) and 51 months (range 15-79 months), respectively. None of the patients presented adverse radiation effects.

CONCLUSIONS

In the authors' experience, SRS provided excellent LTC without any adverse radiation effects for BMs secondary to ENB.

A Rare Case of Sinonasal Ewing Sarcoma With Radiologic-Pathologic Correlation

An 89-year-old male presented with syncope and worsening difficulty in breathing through the left nostril. Computed tomography demonstrated a tumor in the anterior ethmoid air cells and maxillary sinus, which extended into the frontal lobe. Magnetic resonance imaging similarly demonstrated an aggressive lesion. This mass was difficult to differentiate from more commonly seen lesions at this location such as an esthesioneuroblastoma or nasopharyngeal carcinoma. Direct visualization, biopsy, and subsequent pathologic analysis eventually confirmed the diagnosis of malignant Ewing sarcoma (EWS). Our case explores the radiological findings of EWS originating from the ethmoid sinus, compares EWS with other common carcinomas in the same location, confirms the diagnosis through pathological correlation, and investigates the prognosis and treatment of these lesions. This case highlights the importance of a multidisciplinary approach to diagnose EWS when it occurs in an atypical location. The clinical team relied on input from the radiology, surgery, ENT, neurology, and pathology departments to make an accurate diagnosis and plan treatment for this aggressive tumor.

Comparing the role of different treatment modalities in locoregionally advanced olfactory neuroblastoma: The 20-year clinical experience of a single institution

BACKGROUND

The clinical value of different treatment modalities, especially systemic chemotherapy (CT) in patients with locoregionally advanced olfactory neuroblastoma (LA ONB) remains unclear.

METHODS

Patients with LA ONB from 2000 to 2020 at our center were collected retrospectively. The entire cohort was divided into combined systemic and local therapy (CSLT) versus local therapy (LT) groups (grouping method 1), and the same cohort was divided into neoadjuvant chemotherapy (NAC) versus non-NAC groups (grouping method 2). CSLT group included patients treated with CT + LT. LT group included patients treated with surgery (SG), radiotherapy (RT), concurrent chemoradiotherapy (CCRT), or any combination of the above methods. LT group was further divided into mono-modality local therapy (MOLT) group and multi-modality local therapy (MULT) group. MOLT group included patients treated with RT alone or SG alone. MULT group included patients treated with SG + RT/CCRT, or CCRT alone. NAC group included patients treated with NAC + LT ± adjuvant chemotherapy (ADC). Non-NAC group included patients who received LT ± ADC.

RESULTS

A total of 111 patients with LA ONB were included. The median follow-up was 80.2 months (range, 2.1-254.9). The 5- and 10-year OS rates were 70.2% and 61.3%, respectively. In univariate analysis, patients treated with NAC (n = 43) had significantly better overall survival (OS) compared with those without NAC (n = 68) (p = 0.041). Patients in MULT group (n = 45) had significantly improved OS (p = 0.004) and PFS (p = 0.003) compared with those in MOLT group (n = 15). Multivariate analysis identified NAC and CSLT (n = 51) were independent prognostic factors for superior OS (p = 0.020, p = 0.046).

CONCLUSIONS

Our study suggested that CSLT, especially a combination of NAC and LT, improved the survival of patients with LA ONB. Multiple treatment modalities yielded better PFS and OS compared to single-modality treatment.

Treatment outcomes and prognostic factors of esthesioneuroblastoma-a retrospective study from South India

Esthesioneuroblastoma (ENB) or olfactory neuroblastoma is a rare malignant neoplasm arising from the neural crest cells of the olfactory epithelium. The optimum treatment for this rare disease is still unclear. Most of the available literature on this rare head and neck tumour is limited to small retrospective series and single institutional reports. We conducted a retrospective study to investigate the clinical profile, treatment outcomes and prognostic factors of patients with ENB treated at a tertiary cancer centre in south India. Patients with a histopathological diagnosis of ENB treated from 2000 to 2019 were included. Patient demographics, tumour characteristics, stage, treatment details and outcome data were identified from medical records. Overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method and the log-rank test was used for comparison. The prognostic factors were identified using Cox regression analysis. Forty-two patients underwent treatment for ENB from 2000 to 2019. Twenty-six patients underwent surgery. Twelve patients received radical radiotherapy (RT) while 24 patients underwent adjuvant radiation. After a median follow-up of 71 months, the estimated OS and DFS at 4 years were 64.4% and 54%, respectively. The estimated 4-year OS for modified Kadish A, B, C and D stages was 75.0%, 90.9%, 56.4% and 0%, respectively. Modified Kadish stage, nodal involvement, orbital invasion, intracranial extension, surgery, RT treatment and use of chemotherapy were significant predictors of OS and DFS in univariate Cox regression analysis. Orbital invasion and RT treatment were significant predictors of DFS in the multivariate analysis as well. However, only RT treatment came out to be a significant predictor for OS in multivariate Cox regression analysis. Surgery is the mainstay of treatment. Adjuvant RT may improve local control and survival in advanced cases. Advanced modified Kadish stage, lymph node involvement and orbital invasion are associated with poor outcomes.

Primary Sellar Neuroblastoma Masquerading as a Pituitary Macroadenoma

Olfactory neuroblastomas, or esthesioneuroblastomas, are rare and aggressive malignant tumors that typically arise from the olfactory neuroepithelium in the upper nasal cavity. In rare instances, they can be ectopic originating from areas outside the upper nasal cavity such as the sellar region. These tumors, also known as primary sellar neuroblastomas, may be mistaken for pituitary macroadenomas. We present a rare case of a primary sellar neuroblastoma in a 30-year-old woman with a prior diagnosis of presumed prolactinoma, status post transsphenoidal resection, with residual visual deficits, who presented with worsening vision and headaches. Pituitary magnetic resonance imaging showed a large sellar mass causing compression of the optic chiasm, and invasion of the right cavernous sinus and bilateral cavernous internal carotid arteries. The patient underwent a second transsphenoidal resection. Postoperatively, she developed central adrenal insufficiency, central hypothyroidism, central hypogonadism, and transient syndrome of inappropriate antidiuretic hormone secretion. Owing to rapid tumor regrowth, she underwent a craniotomy with plans for radiation treatment. This condition is challenging to diagnose and has poorly defined clinical management guidelines. An early, aggressive approach with surgical intervention is recommended.

Esthesioneuroblastoma: Management of the N0 neck

Esthesioneuroblastoma is a rare sinonasal malignancy that arises from the olfactory epithelium. The overall incidence of lymph node metastases is 25%. However, neck disease can present in a delayed fashion. As such, management of the clinically negative neck is controversial, with some advocating for elective neck treatment and others recommending observation with salvage treatment if necessary. At this time, no prospective head-to-head comparisons of elective versus salvage treatment have been performed.

Molecular Evidence for Olfactory Neuroblastoma as a Tumor of Malignant Globose Basal Cells

Olfactory neuroblastoma (ONB, esthesioneuroblastoma) is a sinonasal cancer with an underdeveloped diagnostic toolkit, and is the subject of many incidents of tumor misclassification throughout the literature. Despite its name, connections between the cancer and normal cells of the olfactory epithelium have not been systematically explored and markers of olfactory epithelial cell types are not deployed in clinical practice. Here, we utilize an integrated human-mouse single-cell atlas of the nasal mucosa, including the olfactory epithelium, to identify transcriptomic programs that link ONB to a specific population of stem/progenitor cells known as olfactory epithelial globose basal cells (GBCs). Expression of a GBC transcription factor NEUROD1 distinguishes both low- and high-grade ONB from sinonasal undifferentiated carcinoma, a potential histologic mimic with a distinctly unfavorable prognosis. Furthermore, we identify a reproducible subpopulation of highly proliferative ONB cells expressing the GBC stemness marker EZH2, suggesting that EZH2 inhibition may play a role in the targeted treatment of ONB. Finally, we study the cellular states comprising ONB parenchyma using single-cell transcriptomics and identify evidence of a conserved GBC transcriptional regulatory circuit that governs divergent neuronal-versus-sustentacular differentiation. These results link ONB to a specific cell type for the first time and identify conserved developmental pathways within ONB that inform diagnostic, prognostic, and mechanistic investigation.

CyberKnife Radiosurgery for Spinal Leptomeningeal Metastases Secondary to Esthesioneuroblastoma: A Clinical Case Report

Esthesioneuroblastoma (ENB), also known as olfactory neuroblastoma, is a rare malignant tumor of neuroectodermal origin that arises from the olfactory epithelium. We present a case of ENB metastasizing through the leptomeningeal route to the spinal dura, which was treated with CyberKnife (CK) stereotactic radiosurgery (SRS), and aim to assess the safety and effectiveness of SRS in such cases. To the best of our knowledge, this is the first case report in the literature that discusses ENB spinal leptomeningeal metastases treated with CK radiosurgery. We retrospectively review the clinical and radiological outcomes in a 70-year-old female with ENB metastasis to the spine. Progression-free survival (PFS), overall survival (OS), and local tumor control (LTC) are investigated. In our patient, ENB had been diagnosed at the age of 58 years and spinal metastases had been first noted at the age of 65 years. A total of six spinal lesions received CK SRS. Lesions were present at the level of C1, C2, C3, C6-C7, T5, and T10-11. The median target volume was 0.72 cc (range: 0.32-2.54). A median marginal dose of 24 Gy was delivered to the tumors with a median of three fractions to a median isodose line of 80% (range: 78-81). LTC at the 24-month follow-up was 100%. PFS and OS were 27 months and 40 months, respectively. No adverse radiation effects were reported. Even though the treated spinal lesions remained stable, the number of new metastatic lesions had increased with progressive osseous and dural metastatic lesions within the cervical, thoracic, and lumbar spine at the last follow-up. SRS provides relatively good LTC for patients with ENB metastasizing to the spine, with no radiation-induced adverse events.

An atypical Esthesioneuroblastoma of the sphenoid sinus: a case report

Esthesioneuroblastoma (ENB) is a rare tumor, arising from the olfactory epithelium. It manifests as an aggressive tumor in the superior aspect of the nasal cavity. Sinonasal symptoms are the most common. The cervical lymph nodes ensue in nearly 10% of cases and hematogenous metastases are rare. The diagnosis is histological. This tumor is staged using the Kadish et al System. The imaging techniques, using both computed tomography (CT) and MRI provides all the important information required for treatment modality. Today, the standard multimodal treatment combining external craniofacial resection, radiotherapy, and chemotherapy has improved long-term survival.

Case presentation

A 27-year-old male patient with no medical history, complained of a headache, a unilateral right nasal obstruction, epistaxis, and anosmia for 2 months. Nasal endoscopy showed a pinkish-gray mass filling the right nasal cavity. An enhanced-contrast CT scan was performed and objectified a mildly enhancing extensive mass of the sphenoid sinus with bone erosion of the left wall of the sinus and intracranial involvement. An intranasal biopsy was performed, resulting in a histopathological diagnosis of olfactory neuroblastoma. Our case was staged as stage C according to the Kadish staging. The tumor was inoperable, the patient had chemotherapy, radiotherapy, and pain management.

Clinical discussion

ENB is an aggressive malignant tumor derived from the specialized olfactory neuroepithelium of the upper nasal cavity. Several published reports confirm ectopic cases of ENB throughout the nasal cavity and the central nervous system. Because sinonasal malignant lesions are rare and difficult to distinguish from their benign counterparts. ENBs appears as a soft, glistening, polypoidal, or nodular mass covered by intact mucosa or as friable masses with ulceration and granulation tissue. A radiological, CT scan through the skull base and paranasal sinuses with intravenous contrast should be performed. ENBs are solid, enhancing nasal cavity masses that may manifest erosion into nearby osseous. MRI provides better discrimination between tumor and secretions and optimal assessment of orbital, intracranial, or brain parenchymal involvement. The biopsy is the next important step in securing a diagnosis. Classic treatment strategies of ENB are based on surgery or radiotherapy as unique modalities or a combination of surgery and radiation therapy. More recently, chemotherapy has been introduced in the therapeutic armamentarium since ENB has proven to be chemosensitive. The elective neck dissection remains controversial. Long-term follow-up is mandatory for patients with ENB.

Conclusion

While most ENBs originate in the superior nasal vault and present with typical symptoms of nasal obstruction and epistaxis in the late stages of the disease, uncommon manifestations should be considered as well. Adjuvant therapy should be considered in patients with advanced disease and unresectable disease. A continuing follow-up period is needed.

Impact of esthesioneuroblastoma treatment delays on overall patient survival

OBJECTIVES

To characterize clinical factors associated with esthesioneuroblastoma treatment delays and determine the impact of these delays on overall survival.

STUDY DESIGN

Retrospective database analysis.

METHODS

The 2004-2016 National Cancer Database was queried for patients with esthesioneuroblastoma managed by primary surgery and adjuvant radiation. Durations of diagnosis-to-treatment initiation (DTI), diagnosis-to-treatment end (DTE), surgery-to-RT initiation (SRT), radiotherapy treatment (RTD), and total treatment package (TTP) were analyzed. The cohort was split into two groups for each delay interval using the median time as the threshold.

RESULTS

A total of 814 patients (39.6% female, 88.5% white) with mean ± SD age of 52.6 ± 15.1 years who underwent both esthesioneuroblastoma surgery and adjuvant radiotherapy were queried. Median DTI, DTE, SRT, RTD, and TTP were 34, 140, 55, 45, and 101 days, respectively. A significant association was identified between increased regional radiation dose above 66 Gy and decreased DTI (OR = 0.54, 95% CI 0.35-0.83, p = 0.01) and increased RTD (OR = 3.94, 95% CI 2.36-6.58, p < 0.001) durations. Chemotherapy administration was linked with decreased SRT (OR = 0.64, 95% CI 0.47-0.89, p = 0.01) and TTP (OR = 0.59, 95% CI 0.43-0.82, p = 0.001) durations. Cox proportional-hazards analysis revealed that increased RTD was associated with decreased survival (HR = 1.80, 95% CI 1.26-2.57, p < 0.005), independent of age, sex, race, regional radiation dose, facility volume, facility type, insurance status, modified Kadish stage, chemotherapy status, Charlson-Deyo comorbidity index, and surgical margins.

CONCLUSIONS

Delays during, and prolongation of radiotherapy for esthesioneuroblastoma appears to be associated with decreased survival.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:764-772, 2023.

Lymph node metastasis from olfactory neuroblastoma at presentation and as disease relapse: A systematic review and proportion meta-analysis of prevalence data and variables influencing regional control

BACKGROUND

Aim of this study is to investigate the prevalence of cervical nodal metastasis at presentation and as disease relapse in primary, treatment-naive olfactory neuroblastoma (ONB), and to review treatment modalities, risk factors for regional failure and survival outcomes according to nodal status.

METHODS

A systematic review and proportion meta-analysis were conducted following PRISMA guidelines based on PubMed, Web of Science, and Scopus.

RESULTS

Eighteen articles were examined. The pooled proportion of patients with nodal metastasis at presentation (11.5%) was comparable to that of cN0 patients not receiving elective neck treatment developing nodal metastasis during follow-up (12.3%). Of the latter, most were Kadish stage C tumors (85.5%).

CONCLUSIONS

Cervical involvement is common both at presentation and during follow-up of cN0 ONB. The highest risk of developing late nodal metastasis is seen in cN0 patients with Kadish stage C tumors not receiving elective neck treatment. Elective cN0 neck treatment should be encouraged in selected patients to increase regional control.

Recurrent Esthesioneuroblastoma: Long-Term Outcomes of Salvage Therapy

INTRODUCTION

Esthesioneuroblastoma (ENB) is a rare malignant neoplasm arising from the olfactory epithelium of the cribriform plate. Although survival is excellent with a reported 5-year overall survival (OS) of 82%, recurrence is frequent and occurs in 40-50% of cases. This study investigates the characteristics of ENB recurrence and the subsequent prognosis of patients with recurrence.

METHODS

The clinical records of all patients diagnosed as having ENB with subsequent recurrence at a tertiary hospital from 1 January 1960 to 1 January 2020 were retrospectively reviewed. Overall survival (OS) and progression-free survival (PFS) were reported.

RESULTS

A total of 64 out of 143 ENB patients had recurrences. In total, 45 out of 64 recurrences met the inclusion criteria and were included in this study. From these, 10 (22%) had a sinonasal recurrence, 14 (31%) had an intracranial recurrence, 15 (33%) had a regional recurrence, and 6 (13%) had a distal recurrence. The average interval from initial treatment to recurrence was 4.74 years. There were no differences in rates of recurrence with respect to age, sex, or types of surgery (endoscopic, transcranial, lateral rhinotomy, and combined). The time to recurrence was shorter for Hyams grades 3 and 4 compared to Hyams grades 1 and 2 (3.75 years vs. 5.70 years, p < 0.05). Patients with recurrence limited to the sinonasal region had a lower overall primary Kadish stage compared to recurrences beyond the sinonasal region (2.60 vs. 3.03, p < 0.05). A total of 9 (20%) out of 45 patients developed secondary recurrence. Following recurrence, the subsequent 5-year OS and PFS were 63 and 56%, respectively. The mean time to secondary recurrence after treatment of the primary recurrence was 32 months, which was significantly shorter than the time to primary recurrence (32 months vs. 57 months, p = 0.048). The mean age of the secondary recurrence group is significantly older than the primary recurrence group (59.78 years vs. 50.31 years, p = 0.02). No statistically significant differences were observed between the secondary recurrence group and the recurrence group in terms of their overall Kadish stages or Hyams grades.

CONCLUSIONS

Following an ENB recurrence, salvage therapy appears to be an effective therapeutic option with a subsequent 5-year OS of 63%. However, subsequent recurrences are not infrequent and may require additional therapy.

Sinonasal Schwannomas: Imaging Findings and Review of Literature

OBJECTIVE

Schwannomas are common nerve sheath tumors and may occur anywhere in the body. 4% of head and neck schwannomas occur in the sinonasal cavity, and fewer yet have an intracranial component, making these presentations extremely rare. Furthermore, schwannomas present with nonspecific imaging signs and can only be definitively differentiated via histopathologic review, leading to misdiagnosis as various nasal tumors. We aim to conduct a review of published literature on sinonasal schwannomas with and without intracranial extension and provide additional case representations.

METHODS

A literature review was conducted using the PubMed Database with the terms "sinonasal schwannoma," "intracranial," "anterior skull base," and "schwannoma." Results were reviewed, and additional cases identified were referenced and included in the study. Inclusion criteria were any case with intracranial extension of the schwannoma. There were no exclusion criteria. Review data was compiled into Excel and used for data analysis and comparison. Additionally, a search was done within our institution to identify additional cases of sinonasal schwannoma.

RESULTS

We identified 17 cases of sinonasal schwannoma with intracranial extension, five from our institution and twelve from literature. Analysis revealed: 8 females (47%), 9 males (53%), 9 patients presented with headaches (53%), 6 patients presented with anosmia (35%), 4 patients presented with nasal obstruction (24%), and 2 patients with no symptoms (12%). Mean age and median were 39.4 ± 10.1 and 40, respectively. For treatment, 4 patients underwent endoscopic resection (24%), 11 underwent craniotomy (65%), and data was unavailable for 2 patients. Post-treatment complications occurred in 6 patients, 5 had CSF leaks (29%) and 1 had a hematoma (6%).

CONCLUSION

We identified and discussed 17 cases of sinonasal schwannoma with intracranial extension. We hope our review provides insight for clinicians to maintain schwannoma as a potential differential when evaluating nasal and anterior skull base masses.

An exceptionally rare case of Cushing's syndrome caused by ectopic ACTH syndrome due to olfactory neuroblastoma in childhood

OBJECTIVES

Ectopic adrenocorticotropic hormone secretion/syndrome (EAS) is caused by excess secretion of ACTH leading to hypercortisolism by non-pituitary, commonly malignant origins. We present a rare case of esthesioneuroblastoma (ENB) complicated by EAS in the follow-up period.

CASE PRESENTATION

A child presented with nasal obstruction at the age of 10 months. Polypoid mass obstructing the right nasal passage was detected. Magnetic resonance imaging (MRI) showed a lesion limited within the nasal cavity. The lesion was completely removed by nasal endoscopic surgery. The pathologic examination revealed a diagnosis of esthesioneuroblastoma. It was confined to the nasal cavity so chemotherapy/radiotherapy was not administered and began to follow up. At 28 months of age, he presented with rapid weight gain. Laboratory data were consistent with Cushing's syndrome (CS). High-dose dexamethasone suppression test and imaging studies led us to think of ectopic ACTH syndrome originated from ENB relapse. After partial resection of the tumor, ketoconazole treatment was started along with chemotherapy. Hypercortisolemia was kept under control with ketoconazole treatment as long as the treatment was maintained.

CONCLUSIONS

Cushing syndrome is a rare endocrine disorder. Adrenal sources of hypercortisolism and ectopic sources of ACTH overproduction should be investigated especially in young children.

Esthesioneuroblastoma (Olfactory Neuroblastoma): Overview and Extent of Surgical Approach and Skull Base Resection

Esthesioneuroblastoma is a rare malignancy originating from the olfactory epithelium. Treatment consists of surgical resection with strong consideration for adjuvant treatment in advanced Kadish stage and high Hyams grade. In the modern era, overall outcomes for esthesioneuroblastoma are favorable compared with many other sinonasal malignancies with 5-year overall survival estimated to be 80%. When selecting the optimal surgical approach, the surgeon must consider the approach that will allow for a negative margin resection and adequate reconstruction. In appropriately selected patients, endoscopic outcomes appear at least equivalent to open approaches and unilateral endoscopic approach may be used in select olfactory preservation cases.

Olfactory Neuroblastomas: What Actually Happens in the Long-Term?

Objective: The aim of this study was to investigate the long-term oncologic outcome and review the state of the art in the management of olfactory neuroblastomas. Material and Methods: The records of all patients treated for olfactory neuroblastomas in two academic departments between 1975 and 2012 were evaluated retrospectively. Data on epidemiological parameters were collected (age, gender), along with staging (Kadish, Morita), histologic grading (Hyams), time and form of treatment, locoregional control, and disease-specific and overall survival. Patients with other malignant diseases, distant metastases of olfactory neuroblastomas at the time of initial diagnosis, a follow-up time of less than 5 years, or insufficient clinical-pathological data were excluded from further analysis. Results: In total, 53 cases made up our final study sample (26 men, 27 women; male–female ratio 0.96:1). Their mean age was 48.6 years (range: 10–84 years). The mean follow-up time was 137.5 months (4–336 months, SD: 85.0). A total of 5 out of 53 study cases (9.4%) showed metastatic involvement of the neck at the time of initial presentation. Local recurrence was detected in 8/53 (15.1%) and regional recurrence in 7/53 of our study cases (13.2%). Three patients (42.8%) from the group of cases with surgery as the sole form of management (7/53, 13.2%) died due to the disease. The cumulative disease-specific survival and overall survivalfor the whole group of patients were 88.6% and 63.6%, respectively. The cumulative disease-specific survival stratified by Kadish A/B vs. Kadish C/D as well as Hyams I/II vs. Hyams III/IV showed superior results for limited tumors, albeit without significance, and low-grade tumors (highly significant difference). Conclusion: Craniofacial or sometimes solely endoscopically controlled resection can warrant resection of the olfactory neuroblastoma with wide margins. However, locoregional failures and distant metastases can occur after a long period of time. The non-negligible incidence of regional recurrences, partly in unusual localizations, leads us to consider the need to identify the “recurrence-friendly” cases and to perform individualized elective irradiation of the neck in cases with high-risk features.

Long-term oncologic outcomes in esthesioneuroblastoma: An institutional experience of 143 patients

OBJECTIVE

Esthesioneuroblastoma (ENB) is a rare malignant neoplasm arising from the olfactory epithelium of the cribriform plate. The goal of this study was to update our oncologic outcomes for this disease and explore prognostic factors associated with survival.

MATERIALS AND METHODS

We performed a retrospective analysis of patients with ENB treated at a single tertiary care institution from January 1, 1960, to January 1, 2020. Univariate and multivariate analysis was performed. Overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were reported.

RESULTS

Among 143 included patients, the 5-year OS was 82.3% and the 5-year PFS was 51.6%; 5-year OS and PFS have improved in the modern era (2005-present). Delayed regional nodal metastasis was the most common site of recurrence in 22% of patients (median, 57 months). On univariate analysis, modified Kadish staging (mKadish) had a negative effect on OS, PFS, and DMFS (p < 0.05). Higher Hyams grade had a negative effect on PFS and DMFS (p < 0.05). Positive margin status had a negative effect on PFS (p < 0.05). Orbital invasion demonstrated worsening OS (hazard ratio, 3.1; p < 0.05). On multivariable analysis, high Hyams grade (3 or 4), high mKadish stage (C+D), and increasing age were independent negative prognostic factors for OS (p < 0.05). High Hyams grade (3+4), high mKadish stage (C+D), age, and positive margin status were independent negative prognostic factors for PFS (p < 0.05). High Hyams grade (3+4) was an independent negative prognostic factor for DMFS (p < 0.05).

CONCLUSIONS

Patients with low Hyams grade and mKadish stage have favorable 5-year OS, PFS, and DMFS.

Cystic Intracranial Recurrence of Olfactory Neuroblastoma without Accumulation on Fluorine-18-fluorodeoxyglucose Positron Emission Tomography

A 66-year-old man underwent multimodal treatment for olfactory neuroblastoma (ONB). When he was 72 years old, a cystic intracranial lesion without accumulation on fluorine-18-fluorodeoxyglucose positron emission tomography was detected. Surgical resection was performed when the patient was 73 years old. The pathological examination revealed recurrence of ONB, and the patient underwent focal irradiation. At age 81, he presented with a second recurrence in the right occipital lobe with radiological and pathological findings similar to the prior recurrence. This case suggests that pathological confirmation should be considered in cases with atypical radiological findings following the treatment of ONB.

Clinicopathologic features and prognosis of olfactory neuroblastoma with isocitrate dehydrogenase 2(IDH2) mutations

OBJECTIVE

Because of their rarity, it is not known whether isocitrate dehydrogenase 2 (IDH2) mutations are related to olfactory neuroblastoma. We investigated relationships between IDH2 mutations, clinicopathological parameters, and prognosis for olfactory neuroblastoma to establish a molecular classification based on IDH2 mutations.

MATERIALS AND METHODS

An 82-patient cohort was retrospectively screened by immunohistochemistry using a mutation-specific IDH2 antibody and by real-time PCR for IDH2 mutations. We also determined immunohistochemically the expression of chromogranin A, synaptophysin, neuron-specific enolase, CD56, S100, and Ki67.

RESULTS

The two methods for detection of IDH2 mutations had high consistency. Mutation of IDH2 detected by real-time PCR was correlated with higher Kadish stage, Hyams grade, and Ki67 proliferation index. Mutation of IDH2 was negatively correlated with expression of chromogranin A, synaptophysin, CD56, and S100. Kaplan-Meier analysis showed that an IDH2 mutation, high Hyams grade, and Ki67 index were associated with poor overall survival. Hyams grade and IDH2 mutation were independent prognostic factors in multivariable analysis.

CONCLUSIONS

Immunohistochemistry was a reliable method to assess the mutation status of IDH2. Tumors with IDH2 mutations represented a distinct subset with aggressive behavior and poor prognosis. The gene status of IDH2 can be a major molecular classification criterion in olfactory neuroblastoma.

Regional Recurrences and Hyams Grade in Esthesioneuroblastoma

Objective  The aim of this study is to determine if Hyams grade may help predict which patients with esthesioneuroblastoma (ENB) tumors are likely to develop regional recurrences, and to determine the impact of tumor extent on regional failure in ENB patients without evidence of nodal disease at presentation. Design  The study was designed as a retrospective review for ENB patients. Settings  The study was prepared at tertiary care academic center for ENB patients. Participants  Patients with ENB were included in the study. Main Outcome Measures   Oncologic outcomes (5-year regional and locoregional control (LRC) and overall survival) in patients with Hyams low grade versus high grade. Oncologic outcomes based on radiographic disease extent. Results  A total of 43 patients were included. Total 25 patients (58%) had Hyams low-grade tumor, and 18 (42%) had high-grade tumor. Of the 34 patients without regional disease at presentation, 8 (24%) were treated with elective nodal radiation. There were no statistically significant differences in 5-year regional control in the Hyams low-grade versus high-grade groups (78 vs. 89%; p  = 0.4). The 5-year LRC rates in patients with low grade versus high grade were 73 versus 89% ( p  = 0.6). The 5-year overall survival rates in patients with low-grade versus high-grade tumors were 86 versus 63% ( p  = 0.1). Radiographic extension of disease into the olfactory groove, olfactory nerve, dura, and periorbita were statistically associated with decreased 5-year overall survival (5-year OS 49 vs. 91% [ p  = 0.04], 49 vs. 91% [ p  = 0.04], 44 vs. 92% [ p  = 0.02], and 44 vs. 80% [ p  = 0.04], respectively). Conclusion  ENBs are associated with a risk of regional failure. The current analysis suggests that Hyams low-grade and high-grade malignancies have comparable rates of early and delayed regional recurrences, although small sample size may limit our conclusions.

An olfactory neuroblastoma presenting as posterior reversible leukoencephalopathy syndrome

Olfactory neuroblastomas are rare malignancies of the nasal and sinus cavities. They have been associated with paraneoplastic syndromes due to secretion of adrenocorticotropin hormone (ACTH) or antidiuretic hormone. These associated paraneoplastic syndromes can present with a wide variety of symptoms that can make diagnosis of the underlying tumor difficult. Here we present the case of a 23-year-old woman who had a seizure due to the development of posterior reversible leukoencephalopathy syndrome because of secondary hypertension due to Cushing's syndrome, which was in turn found to be due to ectopic ACTH production from a metastatic olfactory neuroblastoma.

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.

Survival Associations between Patient Age and Treatment Modality in Olfactory Neuroblastoma: A Retrospective Population-Based Study

Olfactory neuroblastoma (ONB) is a rare neuroepithelial-derived malignancy that usually presents in the nasal cavity. The rarity of ONB has led to conflicting reports regarding associations of patient age and ONB survival and outcome. Moreover, long-term outcomes of chemotherapy and other treatment modalities are speculated. Here, we aimed to compare survival outcomes across age groups through time and determine associations between treatment modality and survival. In this retrospective population-based study, we analyzed the SEER 2000–2016 Database for patients with ONB tumors. Using Kaplan–Meier survival analysis, a significant effect of age and cancer-specific survival (CSS) was observed; geriatric ONB patients had the lowest CSS overall. Generalized linear models and survival analyses demonstrated that CSS of the pediatric patient population was similar to the geriatric group through 100 months but plateaued thereafter and was the highest of all age groups. Radiation and surgery were associated with increased CSS, while chemotherapy was associated with decreased CSS. GLM results showed that tumor grade, stage and lymph node involvement had no CSS associations with age or treatment modality. Our results provide insight for future investigations of long-term outcomes associated with ONB patient age and treatment modality, and we conclude that survival statistics of ONB patients should be analyzed in terms of trends through time rather than fixed in time.

The role of chemotherapy in the management of olfactory neuroblastoma: A 40-year surveillance, epidemiology, and end results registry study

BACKGROUND

In this retrospective surveillance, epidemiology, and end results (SEER) registry analysis, we investigated the role of chemotherapy (CT) in the treatment of olfactory neuroblastoma (ON), an exceedingly rare sino-nasal tumor typically treated with surgery and/or radiation therapy (RT).

METHODS

We analyzed all patients in the SEER registry diagnosed with a single primary malignancy of ON, a primary tumor site within the nasal cavity or surrounding sinuses, sufficient staging information to derive Kadish staging, and >0 days of survival, ensuring follow-up data. Receipt of CT in the SEER registry was documented as either Yes or No/Unknown.

RESULTS

Six hundred and thirty-six patients were identified. One hundred and ninety-five patients received CT as part of their treatment for ON. Following propensity score matching and inverse probability of treatment weighting, there was inferior overall survival (OS) (HR 1.7, 95% CI: 1.3-2.2, P = .001) and cancer-specific survival (CSS) (HR 1.8, 95% CI: 1.3-2.4, P < .001) for patients who received CT compared to those who were not treated with CT or had unknown CT status. On subgroup analysis, the only patient population that derived benefit from CT were patients who did not receive surgery and were treated with CT and/or RT (HR 0.3, 95% CI: 0.14-0.61, P < .001).

CONCLUSIONS

Based on this retrospective SEER registry analysis, the use of CT in the management of ON is associated with decreased OS. Our analysis suggests that patients who are considered nonsurgical candidates may benefit from the addition of CT.

[Clinical analysis of 31 cases of esthesioneuroblastoma]

Objective:To investigate the clinical characteristics and prognostic factors of esthesioneuroblastoma. Methods:The clinical data of 31 patients with esthesioneuroblastoma were retrospectively studied. Results:The average time from first onset to diagnosis in 31 patients was 7.84 months, among which 3 patients（9.68%） had cervical lymph node metastasis at the first visit. By the end of follow-up, there were 25 coexisting cases and 6 deaths. The mean recurrence time of 6 patients was 10.6 months. There were 6 patients with distant metastasis, including 4 patients with cervical lymph node metastasis, 1 patient with liver metastasis and 1 patient with bone metastasis. Modified Kadish stage, different treatment methods, recurrence, first diagnosis of cervical lymph node metastasis, and distant metastasis were all factors affecting the prognosis of the patients. Conclusion:The incidence of esthesioneuroblastoma is low and the comprehensive treatment of surgery combined with radiotherapy is the optimal treatment plan. Patients with low Kadish staging, surgical combined with radiotherapy, no recurrence, no initial cervical lymph node metastasis, and no distant metastasis have a better prognosis.

The value of 68 Gallium-DOTATATE PET/CT in sinonasal neuroendocrine tumor management: A case series

BACKGROUND

⁶⁸ Gallium-DOTATATE (⁶⁸ Ga-DOTATATE) is a somatostatin analog used as a PET tracer to successfully identify neuroendocrine tumors (NETs). Due to the rarity of sinonasal NETs, there are few recommendations for ⁶⁸ Ga-DOTATATE imaging in these patients.

METHODS

We discussed the impact of ⁶⁸ Ga-DOTATATE imaging on the management of six sinonasal NET cases and reviewed existing literature.

RESULTS

⁶⁸ Ga-DOTATATE PET/CT revealed an unknown primary in one case and identified metastatic disease in a primary sinonasal small cell neuroendocrine carcinoma (SNEC) patient missed on conventional imaging. In two esthesioneuroblastoma (ENB) patients, ⁶⁸ Ga-DOTATATE detected abnormal radiotracer uptake not present on 18F-FDG PET/CT and identified a patient for treatment with ¹⁷⁷ Lu-DOTATATE.

CONCLUSIONS

This is the one of the first few reports, and the largest series to our knowledge, demonstrating the utility of ⁶⁸ Ga-DOTATATE imaging for primary sinonasal SNEC and ENB. Further study is required to determine its role in sinonasal NET management.

Long-Term Survival Outcomes and Treatment Experience of 64 Patients With Esthesioneuroblastoma

Background: Esthesioneuroblastoma (ENB) is a rare sinonasal malignancy, lacking a unified staging system and treatment. Management at a single center was retrospectively evaluated to inform future treatment options and prognostic factors. Methods: Clinical data of 64 consecutive ENB patients, including prognostic factors and treatment methods, were reviewed retrospectively. Data were collected to calculate overall survival (OS) and progression free survival (PFS). Results: The majority of tumors 84.4% were within Kadish C stage, 79.7% were within T3 or T4, and 64.0% were within Hyams grade III or IV. A total of 50 (78.1%) patients received surgery and combined radiotherapy with or without chemotherapy, 10 (15.6%) received surgery with or without chemotherapy alone, and 4 (6.3%) received radiotherapy with or without chemotherapy alone. The majority of patients (79.7%) underwent endoscopic resection (endoscopic and endoscopically assisted). Surgery combined with radiotherapy with or without chemotherapy resulted in significantly better OS (84.4 vs. 50.6%, 84.4 vs. 37.5%) compared to surgery alone and radiotherapy alone (P = 0.0064). Endoscopic surgery group (endoscopic and endoscopically assisted) resulted in significantly better 5-year PFS (61.7 vs. 22.2%) compared to the open surgery group (P < 0.001). Although endoscopic surgery group was not a statistically significant predictor of 5-year OS (P = 0.54), the 5-year OS was 79.3% for the endoscopic surgery group and 76.2% for the open surgery group. A Cox regression analysis identified intracranial extension and surgery combined with radiotherapy as independent factors affecting 5-year OS while cervical lymph node metastasis and Hyams grade IV as independent factors affecting 5-year PFS. Conclusion: Our findings suggest that surgery combined with radiotherapy is the best treatment approach for ENB. For advanced tumors, endoscopic surgery is an effective treatment, and its survival rate is equal to or better than open surgery.

Correlating the treatment outcome with tumor staging, grading, and various treatment modalities in patients with esthesioneuroblastoma

Objective:

Although till date no management protocol for esthesioneuroblastoma (ENB) has been standardized due to tumor rarity, still multimodality approach shows better treatment outcomes as compared to surgery alone. The objective of this study was to analyze the clinicopathological spectrum of ENB and to correlate treatment response with tumor staging, histopathological grading, and various treatment modalities.

Materials and Methods:

Twenty-one consecutive patients with biopsy-proven ENB were studied and evaluated for response to treatment in the form of complete tumor resolution. Results were analyzed and correlated with stage and grade of tumor and form of therapy received.

Results:

There was male preponderance (3.2:1) with age ranging between 7 and 63 years (median of 25 years). Survival rates significantly dropped with increasing tumor stage (63.6% in stages A and B vs. 30% in stages C and D) and grade (100% in Grades 1 and 2 vs. 31.25% in Grades 3 and 4). The recurrence rate was 80% in surgery alone group, which came down to 43.7% if surgery was supplemented with other modalities. In cases where multimodality treatment plan was used, endoscopic procedures fared equally as open surgical procedures.

Conclusion:

Hyam's grade and Kadish stage are important prognostic indicators of treatment outcome, with survival rates dropping with increasing tumor stage and grade. Multimodality treatment protocols have improved the disease outcome, making endoscopic surgery equivalent to radical surgeries regarding result outcomes and giving other advantages such as better cosmesis, less treatment-related morbidities, decreased hospital stay, and better cost-effectiveness.

Proposal of a TNM classification-based staging system for esthesioneuroblastoma: More precise prediction of prognosis

BACKGROUND

Esthesioneuroblastoma (ENB) is a rare malignant neoplasm. Currently, no consistent and universal staging system for ENB exists. The aim of this study is to propose a TNM-based classification.

SUBJECTS AND METHODS

Hundred and forty-two patients from our institution, with ENB pathologically confirmed between July 1978 and December 2018, were reviewed. All patients were restaged according to the Kadish stage, Morita stage and American Joint Committee on Cancer (AJCC) T classification from clinical and radiological data. Multivariate Cox proportional hazard regression analyses were performed to determine the impact of various factors. The goodness-of-fit and predictive accuracy of the different staging systems were calculated using R software.

RESULTS

The median follow-up time was 57 months (range: 4-229 months). According to the Kadish system, the 5-year overall survival (OS) for patients with stage A, B and C was 100%, 83.6% and 64.2%, respectively (P = .055). With respect to the Morita classification, 5-year OS for stages A, B, C and D was 100%, 83.6%, 70.7% and 50.0%, respectively (P = .004). Analysis based on the proposed staging model demonstrated 5-year OS for stage I, II, III and IV disease was 100%, 88.9%, 75.9% and 49.0%, respectively (P < .001). In separate multivariate Cox regression models, only the novel staging system exhibited independent effects on OS (P = .004); the Akaike information criterion and Harrell's concordance index were also superior to those calculated for the Kadish or Morita systems.

CONCLUSIONS

The proposed TNM-based staging system offers an improved prognostic assessment for patients with ENB. Further verification and refinement from additional dataset application is required.

Surgery as Single-Modality Treatment for Early-Stage Olfactory Neuroblastoma: An Institutional Experience, Systematic Review and Meta-analysis

BACKGROUND

For olfactory neuroblastoma (ONB), the combination of surgical tumor resection and radiation therapy (RT) has been considered the "gold standard" in treatment protocols intended to cure.

OBJECTIVE

To summarize evidence on the treatment of ONB using surgery alone.

METHODS

A retrospective institutional case series, a systematic review of the literature, and an individual patient data (IPD) meta-analysis on only surgically treated ONB patients.

RESULTS

At our institution, a total of 10 patients were treated through surgery alone and remained alive and free of disease at last follow-up. The IPD meta-analysis on 128 patients revealed a disease-free survival (DFS) and overall survival (OS) of 67.7% and 75.4% at 5 years and 57.1% and 71.9% at 10 years, respectively. Univariate analysis showed that Kadish stage C/D and Hyams grading III//IV significantly affected OS (P = 0.000 and P = 0.000) and DFS (P = 0.000 and P = 0.002). For low-risk patients, the DFS was 80.6% at 5 years and 67.8% at 10 years, respectively.

CONCLUSIONS

Surgery alone is an equivalent alternative to combined treatment in carefully selected low-risk ONB patients with better outcome measures than previously reported.

Short-Term Morbidity and Predictors of Adverse Events Following Esthesioneuroblastoma Surgery

INTRODUCTION

The short-term adverse events and predictors of morbidity in surgical resection of esthesioneuroblastoma (ENB) are largely unknown, and investigating these variables can help direct planning for at-risk patients.

METHODS

The 2005-2017 National Surgical Quality Improvement Program database was queried to identify patients with a diagnosis of ENB undergoing skull base surgery for tumor resection. Information regarding demographics, patient morbidity score, pre-operative and intra-operative data, and post-operative outcomes were extracted. Cox proportional hazard analysis was utilized to assess complication and readmission/reoperation rates.

RESULTS

A total of 95 patients undergoing skull base surgery for resection of ENB were included. Mean age, BMI, operation time, and post-operative length of stay (LOS) of the cohort were 53.6 ± 16.2 years, 29.1 ± 6.5, 392.0 ± 204.6 minutes, and 5.8 ± 4.6 days, respectively. In total, 31 patients (32.6%) experienced at least one 30-day adverse event, which included blood transfusion intra-operatively or within 72 hours from the operation (22.1%), readmission (10.7%), intubation >48 hours (7.4%), reintubation (4.2%), organ or space infection (4.2%), reoperation (4.0%), superficial or deep surgical site infection (2.1%), sepsis (2.1%), pulmonary embolism (1.1%), and myocardial infarction (1.1%). Patients who experienced at least one adverse event had significantly higher operation time (486.8 ± 230.4 vs. 347.5 ± 176.2 minutes, p = 0.002), LOS (9.2 ± 5.6 days vs. 4.2 ± 3.0, p < 0.001), and lower hematocrit (37.3 ± 5.9 vs. 41.2 ± 3.8, p < 0.001) and albumin levels (3.8 ± 0.6 vs. 4.2 ± 0.3, p = 0.009). Patients with a higher American Society of Anesthesiologists (ASA) score (HR = 2.39; p = 0.047) or longer operation time (HR = 1.004; p = 0.001) had a significantly higher risk for experiencing adverse events. Obesity was not associated with different intra- or post-operative outcomes, but older patients had shorter operations (p = 0.002) and LOS (p = 0.0014).

CONCLUSION

Longer operation time and lower pre-operative hematocrit and albumin levels may all increase complication rates in ENB resection. Patients with high ASA score or more advanced age may have different short-term outcomes.

Treatment Strategies and Outcomes of Pediatric Esthesioneuroblastoma: A Systematic Review

Introduction: Esthesioneuroblastoma, also known as olfactory neuroblastoma, is a small round blue cell tumor of nasal neuroepithelium first described in 1924. Though this tumor is especially rare in the pediatric population with an incidence of <0.1 per 100,000, it is the most common pediatric nasal cavity neoplasm. The purpose of this systematic review is to examine the treatment modalities utilized for pediatric esthesioneuroblastoma and overall survival.

Methods: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Pubmed, EMBASE, and Ovid MEDLINE databases were queried for studies pertinent to treatment modalities for pediatric esthesioneuroblatoma and survival outcomes.

Results: Two hundred and seventy-sixth articles were identified, with seven meeting inclusion criteria. Ninety-four patients with an age range of 0.9–21 years old with esthesioneuroblastoma were included. Nearly 90% of patients were of stage Kadish B or C at time of presentation, while 20% presented with cervical lymphadenopathy. Only about 10% of patients underwent single modality therapy. Overall, 5-year survival ranged from 44 to 91% with a median follow-up of 3–13 years.

Conclusion: Children with esthesioneuroblastoma usually present at an advanced stage and undergo multi-modality therapy at a higher rate than adult patients. There is a wide range of documented overall survival though this lack of precision could be due to a paucity of patients.

Intensity-Modulated Radiation Therapy for Esthesioneuroblastoma: 10-Year Experience of a Single Institute

Objectives: To evaluate efficacy and safety of intensity-modulated radiotherapy (IMRT) in the management of esthesioneuroblastoma (ENB). Methods and Materials: A retrospectively analysis of 52 ENB patients treated with IMRT between 8/2008 and 8/2018 was performed. Thirteen of the 44 patients (29.5%) with newly diagnosed and 2 of the 8 patients with recurrent disease presented regional lymph node metastasis. The median dose of IMRT was 66 (range 52.5-75) Gy for all patients. Elective nodal irradiation (ENI) was provided to all excluding 6 patients in this cohort. Results: With a median follow-up time of 32.5 (6~121) months, the 3-year overall survival (OS), progression-free survival (PFS), local progression-free survival (LPFS), regional progression-free survival (RPFS), and distant metastasis-free survival (DMFS) rates for the entire cohort were 89.7, 69.5, 89.7, 95.1, and 85.4%, respectively. Multivariate analysis revealed that N-classification (N- vs. N+) at presentation was the only significant prognosticators for PFS. No significant prognosticator was identified for other survival outcome. No severe (i.e., grade 3 or 4) IMRT-induced acute toxicity was observed. Severe late toxicities were infrequent (11.5%), which included dysosmia (3.8%), hearing loss (3.8%), radiation brain injury (1.9%), and temporal lobe necrosis (1.9%). Moreover, late ocular toxicity secondary to IMRT was not observed. Conclusion: IMRT produced acceptable 3-year outcomes in terms of OS (89.7%), LPFS (89.7%), and RPFS (95.1%) rates without substantial late adverse effects. Further investigations for a more effective systemic strategy for distant disease control as well as a precision radiation technique for further improvement in local control are needed.

Comparison of Open and Endoscopic Approaches in the Resection of Esthesioneuroblastoma

BACKGROUND

Olfactory neuroblastoma, or esthesioneuroblastoma (ENB), is an uncommon sinonasal malignancy arising from olfactory neuroepithelium that is optimally treated with surgical resection. The objective of this study is to determine preoperative predictors of undergoing open versus endoscopic approach for ENB and to investigate significant postoperative survival outcomes between the two surgical approaches.

METHODS

The National Cancer Database (NCDB) was queried for cases of ENB histology that were treated surgically from 2010 to 2015. Groups were stratified into open or endoscopic approach cohorts. Patient demographics, tumor characteristics, treatment modality, and 5-year overall survival were compared between the two groups using Chi-Square analysis and Kaplan-Meier survival analysis. Cases were classified as Kadish stage A, B, C, or D based on the "Collaborative Stage-Extension" codes in NCDB.

RESULTS

Of 533 patients meeting inclusion criteria, 276 (51.8%) patients underwent open, and 257 (48.2%) patients underwent endoscopic surgical approaches. Patients undergoing endoscopic surgery were more likely to be Kadish stages A and B and less likely to be stages C and D (P = .020). Those undergoing endoscopic approach overall had a shorter mean hospital stay postoperatively (3.8 vs. 7.0 days, P < .001). Endoscopic cases had a greater 5-year overall survival (81.9% vs. 75.6%, P = .030); after multivariate regression, there was a trend toward survival benefit to endoscopic surgery that did not reach clinical significance (HR 0.644, [0.392-1.058], P = .083).

CONCLUSION

Although not statistically significant, there is a trend toward increased overall survival with an endoscopic approach in patients undergoing surgery for ENB as compared to an open approach, regardless of Kadish stage. An endoscopic approach is an adequate alternative to an open approach for the surgical treatment of ENB.

Targeted 595-gene genomic profiling demonstrates low tumor mutational burden in olfactory neuroblastoma

BACKGROUND

Olfactory neuroblastoma (ONB) is a rare skull-base malignancy associated with delayed local recurrence. Treatment options in recurrent disease are few and unreliable. We undertook analysis of the ONB exome and immune environment in order to identify potential future immunotherapy treatment options.

METHODS

Retrospective chart review and next-generation targeted 595-gene genomic profiling was performed on a cohort of 14 ONB cases utilizing Tempus proprietary DNA and RNA sequencing technology. Tempus analysis provided a measurement of tumor mutational burden (TMB) and composition of the immune cell infiltrate present in tumor samples. Clinically relevant genomic alterations and associated targeted therapies were identified using cancer.gov and clinicaltrials.gov. TMB was tested by univariate analysis against clinical stage, pathologic grade, recurrence risk, and immune cell infiltration.

RESULTS

The mean age for the subjects was 50 years (range, 13 to 76 years) with a male:female ratio of 1:1. TMB for ONB samples ranged from 1.3 to 9.6 mutations/megabase (Mb) with mean of 3.8 mutations/Mb. Univariate analysis showed no association between TMB and tumor stage, pathologic grade, risk of recurrence, or immune cell infiltration. Genomic profile revealed that 6 of 13 tumors had genetic alterations with targeted therapies in clinical trials, whereas 1 tumor demonstrated KRAS Q61R mutation with U.S. Food and Drug Administration (FDA)-approved targeted therapies.

CONCLUSION

TMB is a novel biomarker guiding the classification of neoplasms in the emerging era of immunotherapy. The characterization of ONB as a low-TMB pathology contributes to the overall taxonomy of all cancers and suggests limited utility of immunotherapy treatment.