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.

Personalized Approach to Olfactory Neuroblastoma Care

Olfactory neuroblastoma (ONB) is an uncommon neuroendocrine malignancy arising from the olfactory neuroepithelium. ONB frequently presents with nonspecific sinonasal complaints, including nasal obstruction and epistaxis, and diagnosis can be obtained through a combination of physical examination, nasal endoscopy, and computed tomography and magnetic resonance imaging. Endoscopic resection with negative margins, with or without craniotomy, as necessary, is the standard of care for definitive treatment of ONB. Regional metastasis to the neck is often detected at presentation or may occur in a delayed fashion and should be addressed through elective neck dissection or radiation. Adjuvant radiotherapy should be considered, particularly in the case of high grade or tumor stage, as well as positive surgical margins. Systemic therapy is an area of active investigation in both the neoadjuvant and adjuvant setting, with many advocating in favor of induction chemotherapy for significant orbital or intracranial involvement prior to surgical resection. Various targeted immunotherapies are currently being studied for the treatment of recurrent or metastatic ONB. Prolonged locoregional and distant surveillance are indicated following definitive treatment, given the tendency for delayed recurrence and metastasis.

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.

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.

The impact of multidisciplinary approaches on the outcomes of olfactory neuroblastoma treated with postoperative radiotherapy

BACKGROUND

We investigated the outcomes of postoperative radiation therapy for olfactory neuroblastoma (ONB) and our cross-departmental collaboration to enhance the effectiveness of cancer treatment.

METHODS

We retrospectively evaluated 22 patients with ONB who underwent postoperative radiotherapy after tumor resection. En bloc resection was performed; pathology specimens were prepared in coronal sections; and irradiation fields were determined after discussion with radiation oncologists, head and neck surgeons, and pathologists.

RESULTS

The overall survival and local control rates were 95.5% and 100%, respectively, at a median 37-month follow-up. The 3- and 5-year disease-free survival (DFS) rates were 64.4% and 56.3%, respectively. Of the 22 patients, 9 (8 Kadish C and 1 Kadish B) had disease recurrence. Of the nine patients, five had positive margins and two had closed margins; cervical lymph node recurrence occurred in six, and distant metastasis with or without cervical lymph node recurrence occurred in three. DFS analysis of risk factors showed no statistically significant differences, but positive margins were a significant recurrence factor in multivariate analysis.

CONCLUSIONS

The local control rate of ONB treated with postoperative radiation therapy was 100%. This may be attributed to cross-departmental cooperation between head and neck surgeons, pathologists, and radiation oncologists, which resulted in accurate matching of CT images for treatment planning with the location of the tumor and positive margins. Longer follow-up periods are required to evaluate the effectiveness of our strategy.

Olfactory Neuroblastoma Causing Cushing's Syndrome Due to the Ectopic Adrenocorticotropic Hormone (ACTH) Secretion: A Case Report

Cushing's syndrome is a constellation of features occurring due to high blood cortisol levels. We report a case of a 47-year-old male with a history of recurrent olfactory neuroblastoma (ONB). He presented with bilateral lower limb weakness and anosmia and was found to have Cushing's syndrome due to high adrenocorticotropic hormone (ACTH) levels from an ectopic source, ONB in this case. Serum cortisol and ACTH levels declined after tumor removal.

Recurrent Wnt Pathway and ARID1A Alterations in Sinonasal Olfactory Carcinoma

Sinonasal tumors with neuroepithelial differentiation, defined by neuroectodermal elements reminiscent of olfactory neuroblastoma (ONB) and epithelial features such as keratin expression or gland formation, are a diagnostically challenging group that has never been formally included in sinonasal tumor classifications. Recently, we documented that most of these neuroepithelial neoplasms have distinctive histologic and immunohistochemical findings and proposed the term "olfactory carcinoma" to describe these tumors. However, the molecular characteristics of olfactory carcinoma have not yet been evaluated. In this study, we performed targeted molecular profiling of 23 sinonasal olfactory carcinomas to further clarify their pathogenesis and classification. All tumors included in this study were composed of high-grade neuroectodermal cells that were positive for pankeratin and at least 1 specific neuroendocrine marker. A significant subset of cases also displayed rosettes and neurofibrillary matrix, intermixed glands with variable cilia, peripheral p63/p40 expression, and S100 protein-positive sustentacular cells. Recurrent oncogenic molecular alterations were identified in 20 tumors, including Wnt pathway alterations affecting CTNNB1 (n = 8) and PPP2R1A (n = 2), ARID1A inactivation (n = 5), RUNX1 mutations (n = 3), and IDH2 hotspot mutations (n = 2). Overall, these findings do demonstrate the presence of recurrent molecular alterations in olfactory carcinoma, although this group of tumors does not appear to be defined by any single mutation. Minimal overlap with alterations previously reported in ONB also adds to histologic and immunohistochemical separation between ONB and olfactory carcinoma. Conversely, these molecular findings enhance the overlap between olfactory carcinoma and sinonasal neuroendocrine carcinomas. A small subset of neuroepithelial tumors might better fit into the superseding molecular category of IDH2-mutant sinonasal carcinoma. At this point, sinonasal neuroendocrine and neuroepithelial tumors may best be regarded as a histologic and molecular spectrum that includes core groups of ONB, olfactory carcinoma, neuroendocrine carcinoma, and IDH2-mutant sinonasal carcinoma.

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.

The Small Round Blue Cell Tumors of Sinonasal Tract: Pathologists Grey Zone

Background

One of the most challenging diagnostic categories in the sinonasal tract includes small-blue-round-cell tumors. These are malignant tumors which show many overlapping histomorphology and immunohistochemistry (IHC) findings. Limited, small biopsy of these not completely excisable tumors adds to the diagnostic confusion.

Materials and Methods

A cross-sectional study was done for 2 years (January 2018-December 2020) in a tertiary care institute, which included 70 cases of tumors of which 49 cases were malignant. All paraffin-embedded blocks were subjected to hematoxylin and eosin stain and IHC followed by molecular study wherever needed.

Results

Of the total cases, small-blue-round-cell tumor constituted the major category comprising 20 rare and interesting cases which included sinonasal undifferentiated carcinoma (4 cases), malignant lymphoma (2 cases of diffuse large B-cell lymphoma and 2 cases of extranodal natural killer/T-cell lymphoma), rhabdomyosarcoma (2 cases), olfactory neuroblastoma (2 cases), malignant melanoma (2 cases), plasmacytoma (2 cases), atypical Ewing's sarcoma (EWS) (1 case), EWS (1 case), nuclear protein in testis (NUT) carcinoma (1 case), and small-cell neuroendocrine carcinoma (1 case).

Conclusion

Tumors of the sinonasal tract are very diverse, more so in small-round-cell tumor which present with a undifferentiated morphology. Thus, accurate diagnosis needs clinicoradiological parameters and special ancillary techniques such as IHC and molecular study in addition to histopathology for early diagnosis and therapy to prevent significant morbidity and mortality caused in these tumors.

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 profiling and immune landscape of olfactory neuroblastoma in China

Background

Olfactory neuroblastoma (ONB) is a rare malignant neoplasm of the olfactory mucosa. The paucity of genomic data has prevented the development of individualized ONB treatments. Here, we investigated the genomic and immune landscape of ONB in Chinese patients.

Methods

Whole exome sequencing (WES) and multiplex immunofluorescence (MIF) analysis were performed on tissue samples from 19 Chinese ONB patients. Patients were divided into low- and high-grade groups.

Results

Overall, 929 nonsynonymous alterations were identified in 18 (94.74%) ONB cases. The most prevalent altered cancer-related genes were CTNNB1 (16%) and ZNRF3 (16%). The most mutated oncogenic pathways were the WNT and RAS pathways. The median tumor mutation burden (TMB) was 0.45, ranging from 0 to 3.25. Only one case expressed PD-L1 (> 1%) in the tumor region. The percentage of CD8+ tumor-infiltrating lymphocytes (TILs) in the tumor region ranged from 0.03% to 84.9%, with a median of 1.08%. No significant differences were observed between the low- and high-grade groups for clinicopathological features, mutant genes, mutant pathways, TMB, tumor neoantigen burden (TNB), mutant-allele tumor heterogeneity (MATH), PD-L1 expression levels, or CD8+ TIL percentage. However, the low-grade group showed significantly more CD68+ macrophages in both the tumor and total region than the high-grade group. Notably, CD68+CD163- macrophages accounted for an average of 80.5% of CD68+ macrophages.

Conclusion

This study presents data on the genomic and immune landscape of ONB cases in China. CTNNB1 and ZNRF3 were the most prevalent altered cancer-related genes. The results of TMB, PD-L1, and CD8+ Tils suggest that ONB may be insensitive to immunotherapy. M1 macrophages may be positively associated with the prognosis of ONB.

Implications for Practice

In this study, the most prevalent altered cancer-related genes were CTNNB1 (16%) and ZNRF3 (16%). The most mutated oncogenic pathways were the WNT and RAS pathways. The median tumor mutation burden (TMB) was 0.45, ranging from 0 to 3.25. Only one (1/15) case expressed PD-L1 (> 1%) in the tumor region. However, the low-grade group showed significantly more CD68+ macrophages in both the tumor and total region than the high-grade group. The higher level of CD68-related macrophages indicates that M1 macrophages potentially play an important role in ONB development that is possibly associated with prognosis.

A case of olfactory neuroblastoma that presented with olfactory dysfunction after a COVID-19 diagnosis

Background

Olfactory dysfunction is associated with conditions such as respiratory tract infections, trauma, sinonasal diseases, and neurodegenerative diseases. During the coronavirus disease 2019 pandemic, there was an increase in patients complaining of olfactory dysfunctions. Many studies have reported that olfactory dysfunction is associated with coronavirus disease 2019 and that the prognosis is usually favorable.

Case presentation

Recently, we experienced a patient with olfactory dysfunction, which was aggravated after a coronavirus disease 2019 diagnosis. The patient had no other medical history, and their nasal endoscopic examination demonstrated no abnormal lesions. Through a psychophysical olfactory function test, the patient was diagnosed with anosmia. A paranasal sinus computed tomography demonstrated sclerotic bony changes in the cribriform plate area. A paranasal sinus magnetic resonance image study found an approximately 3.5 cm-sized olfactory neuroblastoma in the anterior cranial fossa.

Conclusions

We suggest clinicians remember the possibility of underlying intracranial lesions in patients with olfactory dysfunction even during the coronavirus disease 2019 pandemic and understand the guidelines of magnetic resonance imaging when evaluating olfactory dysfunction patients. Furthermore, we recommend that clinicians pay attention to the history of olfactory dysfunction before the symptoms progress and making a coronavirus disease 2019 diagnosis.

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.

Functional Olfactory Neuroblastoma Inducing Symptomatic SIADH

Olfactory neuroblastoma (ONB) is a rare malignancy of the sinonasal cavity, originating from neuroepithelial olfactory cells. Olfactory neuroblastoma can be difficult to diagnose due to its anatomic position and variable symptomatic presentation, leading to diagnosis at a more advanced stage. Here, we present the case of a 35-year-old man with no previous medical history who had a bicycle accident secondary to syncope. He was found to be hyponatremic and suspected to have syndrome of inappropriate antidiuretic hormone secretion (SIADH). In the workup of SIADH, a brain magnetic resonance imaging revealed a mass in the left middle meatus. The lesion secreted inappropriate amounts of ADH, resulting in symptomatic paraneoplastic SIADH. This ultimately led to the early recognition and successful resection of this rare ONB. The patient has remained disease-free for over 5 years. This case is a fortunate example of a functional malignancy of the sinonasal tract that was discovered early and successfully treated as a result of symptomatic SIADH.

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.

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.

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.

Olfactory Neuroblastoma-A Challenging Fine Line between Metastasis and Hematology

Developing in a limited space, rare tumors located at the nose and paranasal sinuses are sometimes difficult to diagnose due to their modest clinical presentation, which is uncorrelated with anatomopathological diversity. This limits the preoperative diagnosis without added immune histochemical study; for that reason, we present our experience with these tumors with the intention of raising awareness. The patient included in our study was investigated by our department through clinical and endoscopic examination, imaging investigations, and an anatomic-pathological study. The selected patient gave consent for participation and inclusion in this research study in compliance with the 1964 Declaration of Helsinki.

Olfactory neuroblastoma with rhabdomyoblasts: A rare case report and review of the literature

Herein we present a case of a 62-year-old male patient who was admitted with the chief complaints of nasal obstruction. The histopathological and immunohistochemical evaluation led to a diagnosis of olfactory neuroblastoma with rhabdomyoblasts. A review of the literature revealed that this is only the fourth case of olfactory neuroblastoma with rhabdomyoblasts. Thus, investigation of more cases and longer follow-up is necessary to understand the disease and identify the best treatment to improve prognosis.

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.

Cytological diagnosis of olfactory neuroblastoma at metastatic sites, with emphasis on role of insulinoma-associated protein 1 immunocytochemistry

BACKGROUND

Olfactory neuroblastoma (ONB) is a rare neuroectodermal tumor with a propensity for lymph node and distant metastases in a proportion of cases, presenting opportunities for cytological diagnosis. Insulinoma-associated protein 1 (INSM1) is a recently identified marker of neuroendocrine differentiation with higher sensitivity and specificity than traditional neuroendocrine immunostains used in diagnosis of ONB.

METHODS

Archival aspirates diagnosed as metastatic ONB were retrieved and reviewed for described characteristics of ONB. Spare direct smears with sufficient cellular material from each case were selected, if available, and immunocytochemistry for INSM1 was performed on the destained alcohol-fixed smears. INSM1 was also performed on non-neuroendocrine malignant round cell tumors (MRCT).

RESULTS

Seven fine needle aspirates (FNA) from five patients were identified, all of which showed a small round cell tumor with fine to coarse granular chromatin. Most cases had moderate to high cellularity, comprised of loosely cohesive clusters and dispersed cells. While two-cell pattern, nuclear streaking and moulding were frequent, background neuropil, fibrillary cytoplasm, and rosettes were uncommon. INSM1 immunostaining performed on spare direct smears showed strong positivity in 30%-100% of tumor cells (mean: 62%) in all aspirates tested (100%). In comparison with other immunostains, INSM1 showed more robust staining, and was easier to interpret. All non-neuroendocrine MRCTs were negative for INSM1.

CONCLUSION

Metatstatic ONB can resemble other small round cell tumors, as all the diagnostic features of ONB may not be readily evident. INSM1 immunocytochemistry has high sensitivity and specificity and can reliably be used as a single marker to support the cytomorphology for a confirmatory diagnosis of ONB, even on direct smears if a cell block is not available.

Case report: The treatment for olfactory neuroblastoma combined with leptomeningeal carcinomatosis via an ommaya reservoir

Olfactory neuroblastoma is a rare neoplasm that usually presents in the upper nasal cavity. Although its prognosis is highly unfavorable, effective treatment options are still lacking. Moreover, there is no standard treatment for patients with olfactory neuroblastoma that progressed to leptomeningeal carcinomatosis. Here we report an uncommon case of a 59-year-old woman who was diagnosed with olfactory neuroblastoma and leptomeningeal carcinomatosis. For a direct delivery of the drugs to the tumor, and to avoid the impact of lumbar puncture on the patient's quality of life, the intravenous chemotherapy plus intrathecal administration of MTX via an Ommaya reservoir was chosen. The results were striking, with the disappearance of tumor cells in the cerebrospinal fluid and the relief of the patient's symptoms with PR. Our result indicates that chemotherapy via an Ommaya reservoir offers a new potential therapy for patients with meningeal metastases.

Persistent pain and numbness in the extremities of an adult due to paraneoplastic peripheral neuropathy caused by olfactory neuroblastoma: A case report

Background

Paraneoplastic peripheral neuropathy (PPN) caused by olfactory neuroblastoma (ONB) has not yet been reported.

Case report

We present a rare case of an adult who hospitalized repeatedly over the past 9 months for persistent pain and numbness in the limbs. This patient was initially diagnosed with chronic inflammatory demyelinating polyneuropathy (CIDP) and treated accordingly, but neurological symptoms did not improve significantly. After this admission, FDG-PET/CT showed focal hypermetabolism of a soft-tissue mass in the nasal cavity, and further lesion biopsy suggested ONB. Combined with positive serum anti-Hu antibody, the diagnosis of PPN associated with ONB was eventually made. Furthermore, the patient's neurological symptoms were relieved after removal of the primary tumor, confirming the accuracy of the diagnosis.

Conclusion

Our case not only expanded the clinical characteristics of ONB but also highlighted the importance of early and comprehensive tumor screening for the diagnosis of PPN.

Severe Thrombocytopenia in a Patient With a History of Olfactory Neuroblastoma

Olfactory neuroblastoma is a rare disease with no randomized clinical trials to guide treatment decision making. Surgery, radiation, and chemotherapy are all used for treatment, and prognosis is mostly determined by the histologic grade and clinical stage. While a neuroendocrine type of neoplasm is similar to small cell carcinoma, metastatic disease in olfactory neuroblastoma is rare. We present a case at our institution of an uncommon clinical course of relapsed olfactory neuroblastoma complicated by severe thrombocytopenia.

Primary Olfactory Neuroblastoma of the Nasopharynx: A Case Report

Olfactory neuroblastoma (ONB) is an ectodermal malignant tumor originating from the olfactory nerve epithelium of the nasal cavity and paranasal sinus. Olfactory neuroblastoma is a rare cancer, with an estimated incidence of 0.4 per million. Olfactory neuroblastoma often occurs in the top of the nasal cavity or near the lateral wall of the middle turbinate, which accounts for approximately 3% to 5% of the nasal cavity and paranasal sinus tumors. Olfactory neuroblastoma primarily in the nasopharynx is rare and tends to be misdiagnosed as nasopharyngeal carcinoma. Herein, we presented a case of ONB of the nasopharynx with recurrent nasopharyngeal tumor and by lymph node metastasis in both sides of the neck 14 months after surgical removal of the primary ONB. Long-term disease-free survival was achieved by definitive radiotherapy. Surgery combined with radiotherapy or definitive radiotherapy is recommended for primary ONB of the nasopharynx, radiotherapy target delineation including nasopharynx and pharyngeal lymph nodes, and neck lymph node drainage area of level Ib, Ⅱ, and Ⅲ.

Posterior Reversible Encephalopathy Syndrome after Lenvatinib Therapy in a Patient with Olfactory Neuroblastoma

Posterior reversible encephalopathy syndrome (PRES) is a rare but severe neurological syndrome that may stem from the use of some medications. Although its mechanism is not well-known, hypertension and endothelial dysfunction have been mentioned in previous literature as being related. Lenvatinib serves as a neoplastic agent that inhibits the tyrosine kinase of vascular endothelial growth factor receptors (VEGFR). VEGFR inhibitors result in endothelial dysfunction and consequent hypertension by nitric oxide pathway suppression and endothelin (ET)-1 stimulation. We hypothesized that VEGFR inhibitors would cause PRES. Herein, we report the case of a 40-year-old man with olfactory neuroblastoma who developed PRES while undergoing treatment with lenvatinib, 7 months after initiation. The symptoms included loss of consciousness and seizures. Fortunately, the symptoms and presence of PRES in imaging resolved, 7 days and 1 month, respectively, after cessation of lenvatinib.

The prognostic value of S-100 protein and Ki-67 index in olfactory neuroblastoma

OBJECTIVE

To evaluate the prognostic value of S-100 protein and Ki-67 labeling index in olfactory neuroblastomas.

METHODS

A retrospective study was conducted on a cohort of 85 patients with olfactory neuroblastomas. The immunohistochemical expression of S-100 and Ki-67 was assessed, and the predictive value of S-100 and Ki-67 was further evaluated. The optimal cutoff value of Ki-67 labeling index was determined using time-dependent receiver operating characteristic curve analysis. Overall survival and progression-free survival were assessed using the Kaplan-Meier method.

RESULTS

A cut-off Ki-67 labeling index value of 67.5% was determined for prognosis in patients with olfactory neuroblastomas. There was a significant correlation between Ki-67 expression and cervical lymph node metastasis (P = 0.049). Compared with S-100 (+), S-100 (-) was associated with a higher rate of lymph node metastasis and a higher level of Ki-67 (P = 0.007, < 0.001, respectively), as well as an advanced Kadish stage (P = 0.037). Survival analyses showed that patients with S-100 (+) had better 5-year overall survival than those with S-100 (-) (P = 0.028), and patients with both S-100 (+) and Ki-67 (<67.5%) had superior 5-year overall survival compared with all the other patients (P = 0.0225).

CONCLUSION

Our findings suggest that S-100 combined with Ki-67 labeling index are reliable prognostic factors in patients with olfactory neuroblastomas.

[One-stage reconstruction of orbital floor combine hard palate defect with the temporalis muscle flap after malignant tumor of maxillary sinus opreation: a case report]

An elderly male case of olfactory neuroblastoma in the left maxillary sinus, who underwent complete resection of the tumor and total maxillectomy. Ipsilateral temporalis muscle flap was used to repair orbital floor and hard palate defects. During the 3-month follow-up, the patient recovered well. It is suggested that one-stage reconstruction with temporalis muscle flap is a good choice for the repair of maxilla defect after resection of maxillary sinus carcinoma, especially in case of invasion of orbital floor and hard palate.

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.

Emerging concepts in sinonasal tumor research

PURPOSE OF REVIEW

Sinonasal malignancies are rare and understudied, often diagnosed at late stages, and may behave aggressively. This review explores investigative diagnostic, therapeutic, and scientific advances specific to sinonasal undifferentiated carcinoma (SNUC), intestinal-type adenocarcinoma (ITAC), and olfactory neuroblastoma (ONB).

RECENT FINDINGS

A number of studies have recently contributed more robust knowledge of the genetic and molecular landscapes of SNUC, ITAC, and ONB. These analyses have identified SMARCB1 and IDH2 mutations in SNUC, potentially allowing for the tumor's subdivision. Recent studies have also defined a role for induction chemotherapy in SNUC. Somatic mutations for ITAC have been identified and may be potentially targetable with FDA approved therapies. Studies defining the tumor microenvironment for ITAC and ONB have introduced the possibility of immune checkpoint inhibition for these tumor types.

SUMMARY

Studies reviewed here detail promising results of the most current and novel characterization of SNUC, ITAC, and ONB genetic and molecular landscapes, which have informed ongoing therapeutic discovery. With continued multi-institutional efforts, the field of sinonasal tumor research will achieve higher disease control and improved treatment outcomes for patients afflicted with these rare cancers.

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.

Radiation-Induced Olfactory Neuroblastoma Following Treatment for NK/T-cell Lymphoma, Nasal Type

Radiation-induced olfactory neuroblastoma (ONB) is an uncommon neoplasm that is generally associated with a poor prognosis. We experienced an unusual case of ONB in a patient who had received previous radiation therapy for extranodal NK/T-cell lymphoma 15 years previously. To our knowledge, this is the first report of a patient with radiation-induced ONB obtaining a complete response (CR) with radical re-irradiation alone. The purpose of this report is to discuss therapeutic strategies for radiation-induced ONB. We report an unusual case of ONB suspected to be a radiation-induced neoplasm in a 33-year-old female who had received 30 Gy of irradiation for extranodal NK/T-cell lymphoma, nasal type (NTCL) 15 years earlier. In this case, the patient presented with nasal obstruction and frequent epistaxis. The patient was diagnosed with ONB based on left nasal biopsy findings. The surrounding normal tissues tolerance of nasal ONB radiation had to be limited, because the previously radiated NTCL was located adjacent to critical organs. We performed intensity modulated radiation therapy (IMRT), which could offer precise irradiation (60 Gy in 2 Gy daily fractions) while sparing critical tissues. The present case was treated with radiation therapy alone, whereas previously reported cases were treated with a combination of chemotherapy and radiation therapy. We treated radiation-induced OBN successfully with radical re-irradiation using IMRT alone and the patient has had no recurrence for 3 years.

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.

Metastatic olfactory neuroblastoma: A small round blue cell puzzle on fine-needle aspiration cytology

Small round blue cell tumors (SRBCTs) are a heterogeneous group of malignant neoplasms that can be challenging to distinguish on fine-needle aspiration (FNA) cytology. Ancillary tests as well as clinico-radiological correlation are often required to make an accurate diagnosis. FNA is a low-cost, low-infrastructure test, making it a coveted diagnostic tool, especially in low-resource settings. Olfactory neuroblastoma (ONB) is a rare SRBCT encountered in both pediatric and adult patients. Awareness of the cytomorphologic and immunocytochemical features of ONB is important in the workup of a SRBCT. This case report describes the primary diagnosis of metastatic ONB on FNA cytology.

IDH2 R172 Mutations Across Poorly Differentiated Sinonasal Tract Malignancies: Forty Molecularly Homogenous and Histologically Variable Cases With Favorable Outcome

IDH2 R172 mutations occur in sinonasal undifferentiated carcinoma (SNUC), large-cell neuroendocrine carcinoma (LCNEC), sinonasal adenocarcinomas, and olfactory neuroblastoma (ONB). We performed a clinical, pathologic, and genetic/epigenetic analysis of a large IDH2-mutated sinonasal tumor cohort to explore their distinct features. A total 165 sinonasal/skull base tumors included 40 IDH2 mutants studied by light microscopy, immunohistochemistry, and genome-wide DNA methylation, and 125 IDH2 wild-type tumors used for comparison. Methylation profiles were analyzed by unsupervised hierarchical clustering, t-distributed stochastic neighbor embedding dimensionality reduction and assessed for copy number alterations (CNA). Thirty-nine histologically assessable cases included 25 (64.1%) SNUC, 8 (20.5%) LCNEC, 2 (5.1%) poorly differentiated adenocarcinomas, 1 (2.7%) ONB, and 3 (7.7%) IDH2-mutated tumors with ONB features. All cases were high-grade showing necrosis (82.4%), prominent nucleoli (88.9%), and median 21 mitoses/10 HPFs. AE1/AE3 and/or CAM 5.2 were positive in all and insulinoma-associated protein 1 (INSM1) in 80% cases. All IDH2 mutants formed one distinct group by t-distributed stochastic neighbor embedding dimensionality reduction separating from all IDH2 wild-type tumors. There was no correlation between methylation clusters and histopathologic diagnoses. Recurrent CNA included 1q gain (79.3%), 17p loss (75.9%), and 17q gain (58.6%). No CNA differences were observed between SNUC and LCNEC. IDH2 mutants showed better disease-specific survival than SMARCB1-deficient (P=0.027) and IDH2 wild-type carcinomas overall (P=0.042). IDH2-mutated sinonasal tumors are remarkably homogeneous at the molecular level and distinct from IDH2 wild-type sinonasal malignancies. Biology of IDH2-mutated sinonasal tumors might be primarily defined by their unique molecular fingerprint rather than by their respective histopathologic diagnoses.

The genomics and epigenetics of olfactory neuroblastoma: A systematic review

BACKGROUND

Olfactory neuroblastoma (ONB) or esthesioneuroblastoma (ENB) is a rare malignancy of the nasal cavity believed to arise from the olfactory epithelium. The goal of this study was to systematically review the genomics, epigenetics, and cytogenetics of ONB and to understand the potential clinical implications of these studies.

METHODS

A systematic literature review was performed for articles published before May 2020 using Cochrane, Embase, Pubmed, and Scopus databases. Inclusion criteria included genomics, cytogenetics, and epigenetics studies on ONB. Exclusion criteria included studies not in English or systematic reviews. Articles and abstracts were reviewed by two independent reviewers to reduce bias during article selection and synthesis of results. Of the 36 studies included in this review, 24 were research articles and 12 were abstracts.

RESULTS

Although recurrent mutations among ONB tumors are uncommon, alterations in TP53, DMD, PIK3CA, NF1, CDKN2A, CDKN2C, CTNNB1, EGFR, APC, cKIT, cMET, PDGFRA, CDH1, FH, SMAD4, FGFR3 and IDH2 genes have been reported in several recent studies. In addition, cytogenetic studies revealed that the landscape of chromosomal aberrations varies widely amongst ONB tumors.

CONCLUSIONS

The rare character of ONB has limited the sample size available for cytogenetic, genomic, and epigenetic studies and contributes to the limitations of this systematic review. Comprehensive genomic and epigenomic studies with larger cohorts are warranted to validate the initial reports summarized in this review and to identify potential therapeutic targets for ONB.

The Treatment Outcomes of Olfactory Neuroblastoma Patients With Frontal Lobe Invasion

Background

To investigate whether frontal lobe invasion (FLI) was an unfavorable prognostic factor in patients with olfactory neuroblastoma (ONB), and to explore the optimal treatment strategy for ONB patients with FLI.

Methods

Some 37 patients with FLI were retrospectively studied, and 74 well-matched patients without FLI were enrolled as the control group. The long-term survivals were compared between the two groups.

Results

No significant differences were found between the two groups in overall survival (OS), progression-free survival (PFS), locoregional failure-free survival (LRFS), and distant metastasis-free survival (DMFS) (all p >0.05). Multivariate analyses showed that FLI wasn't an independent predictor for OS (HR = 1.100, 95% CI = 0.437-2.772, p = 0.840). Among the 37 patients with FLI, patients who received surgery combined with chemo-/radiotherapy showed better OS (89.4% vs. 53.6%, p = 0.001) and PFS (87.8% vs. 53.6%, p = 0.001) compared with those who didn't undergo surgery.

Conclusions

FLI wasn't a poor prognostic factor for ONB patients. Endoscopic resection combined with radiotherapy was an effective therapeutic method for ONB patients with FLI.

Ga-68 DOTATATE Positron Emission Tomography/Computed Tomography in a Rare Case of Esthesioneuroblastoma

We describe the Ga-68 DOTATATE positron emission tomography/computed tomography (PET/CT) findings of a 51-year-old man, operated for right esthesioneuroblastoma. Postoperative Ga-68 DOTATATE PET/CT revealed focal uptake anterior to sphenoid ostium on the right paramedian side, suspicious for residual disease. Magnetic resonance imaging showed an enhancing lesion in posterosuperior nasal cavity on the right side extending into the right sphenoid sinus. He underwent re-surgery and adjuvant chemoradiotherapy. The histopathology revealed residual olfactory neuroblastoma. The follow-up Ga-68 DOTATATE PET/CT was negative. This case emphasizes the role of Ga-68 DOTATATE PET/CT in the management, especially in residual or recurrent disease and potential radiotheranostics for these rare tumors.

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.