Esthesioneuroblastoma of the pituitary gland: a clinicopathological entity? Case report and review of the literature

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.

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.

Olfactory Neuroblastoma: A Novel Site of Presentation

Olfactory neuroblastoma (ONB) or esthesioneuroblastoma is a rare malignant intranasal tumor, commonly originated from upper part of nasal cavity. Majority of cases presented with nasal obstruction or epistaxis. ONB is rarely reported in ectopic locations. Here we present the first-ever documented case of an olfactory neuroblastoma situated anterior to body of maxilla, presented as left sided facial swelling. This case report is aimed at achieving the consideration of this rare tumour as a differential diagnosis in the lesions of the anatomical region surrounding the commonly known site of origin i.e. the sinonasal cavity.

Hemorrhagic Suprasellar Central Nervous System Embryonal Tumor in an Adult: Uncommon Features of an Extremely Rare Neoplasm

BACKGROUND

 Occurrences of suprasellar central nervous system (CNS) embryonal tumors in adults are extremely rare. Hemorrhagic onset is further uncommon, with only anecdotic cases reported in the literature. The authors describe the case of a 57-year-old man affected by a suprasellar CNS embryonal tumor, with hemorrhagic onset and a unique diffusion pattern along the optic pathways.

MATERIAL AND METHODS

 A 57-year-old man presenting with acute visual acuity worsening and left homonymous hemianopia was referred to our hospital. Neuroradiologic studies demonstrated an infiltrating, high-grade lesion involving the optic chiasm and right retrochiasmatic pathways with a hemorrhagic area in the ipsilateral pulvinar.

RESULTS

 The patient underwent microsurgical biopsy. Pathologic assessment confirmed the diagnosis of CNS embryonal tumor, not otherwise specified (NOS) according to the 2016 World Health Organization (WHO) classification of CNS tumors. The patient was referred to a multimodal adjuvant treatment; he eventually died 4 months after surgery. Competent literature has been systematically reviewed in the light of the relevant changes made in the last version of the WHO classification.

CONCLUSION

 Embryonal tumors should be considered in the differential diagnosis for sellar and suprasellar space-occupying lesions, despite the rarity of the disease and the uncommon features at time of presentation. As per our knowledge, this is the first case ever described of hemorrhagic suprasellar embryonal tumor with a diffusion pattern along white matter fibers. Histogenesis, biomolecular and neuroradiologic features, and classification of embryonal tumors are an open field of research, with considerable implications for the definition of better diagnostic pitfalls and therapeutic regimens.

Hypothalamic hormone-producing tumors

The hypothalamus is functional neuroendocrine tissue that is responsible for the synthesis and secretion of peptide hormones that regulate the pituitary and other endocrine functions. Endocrine tumors of the hypothalamus are rare but they provide a model for tumors that have both structural and functional effects. Patients with hypothalamic endocrine tumors suffer mass effects including headaches, visual disturbances, and endocrine dysfunction due to structural damage to hypothalamic nuclei, which regulate appetite, temperature, diurnal rhythms and emotions. In addition, these tumors can secrete hormones that can cause acromegaly, Cushing disease, hyperprolactinemia, and the syndrome of inappropriate antidiuresis. Morphologic classification of these tumors has provided evidence for two classes of tumors, gangliocytomas that are composed of large neurons and neurocytomas that are comprised of small cells; these resemble the variants of magnocellular and parvocellular neurons in the hypothalamic nuclei. Biomarkers are used to classify these tumors and achieve accurate structure-function correlations. While surgery remains the mainstay of therapy, novel medical and radiopharmaceutical approaches are available for patients with progressive and/or unresectable tumors.

A sellar neuroblastoma showing rapid growth and causing syndrome of inappropriate secretion of antidiuretic hormone: A case report

Background:

Sellar neuroblastoma is a very rare entity. We report a rare case of arginine vasopressin (AVP)- producing sellar neuroblastoma presumed to have originated from the lower part of sellar turcica, which grew very rapidly.

Case Description:

A 33-year-old woman was found to have a sellar lesion with a diameter of 18 mm invading into the bilateral cavernous sinus on magnetic resonance imaging (MRI) performed for dizziness. Six years later, when she visited the clinic due to bilateral visual disturbance, MRI showed a rapid growth of the tumor, with a maximal diameter of 56 mm at the current state, strongly compressing the optic nerve and chiasm. Transsphenoidal decompression of the optic chiasm revealed an intact pituitary gland on the top of the tumor. The tumor was composed of neoplastic cells that were immunohistochemically positive for neuronal markers and arginine vasopressin (AVP), but negative for all anterior pituitary hormones, glial fibrillary acidic protein, or thyroid transcription factor-1; these findings were suggestive of sellar neuroblastoma. She underwent 50-Gy radiation therapy, which has controlled the growth for the past 3 years.

Conclusion:

Awareness of rare sellar neuroblastomas will allow the accumulation of clinicopathologic information that may facilitate the understanding of their origin, clinical features, neuroimaging characteristics, and pertinent adjuvant treatment.

Primary sellar neuroblastoma mimicking invasive pituitary adenoma: a systematic review

INTRODUCTION

To report an extremely rare case of sellar neuroblastoma, which mimicked invasive pituitary adenoma with supra- and parasellar extensions, treated through endoscopic endonasal approach. A systematic review of the literature on diagnosis and management of patients affected by sellar neuroblastomas has been performed.

EVIDENCE ACQUIITION

A literature search according to the PRISMA statement was conducted using MEDLINE, Google Scholar, and EBSCO databases, searching for the following MeSH terms: (sellar OR parasellar OR suprasellar OR sphenoidal) AND (neuroblastoma OR extranasal esthesioneuroblastoma OR central neuroblastoma).

EVIDENCE SYNTHESIS

Sixty-eight studies were identified. We included 16 papers in our systematic review, comprising a total of 16 patients, 37.5% males and 62.5% females, with a mean age of 47.2 years. Visual disturbances were found in 56.2% of them, hyperprolactinemia in 43.7%, panhypopituitarism in 12.5%, normal pituitary function in 6.25%, SIADH in 25%, but no data is available in 25% of cases. Brain computed tomography and magnetic resonance imaging showed suprasellar and parasellar extension in 31.2% of patients, isolated suprasellar extension in 50%, isolated parasellar extension only in 6.25%, while in 1 case involvement of the petrous apex was described. Transcranial surgery (TCS) was performed for the removal in 31.2% of patients, transsphenoidal surgery (TSS) in 43.7%, a combined approach in 12.5%, and in two cases surgery was not performed due to poor general patient conditions. Adjuvant treatment with conventional radiotherapy (CRT) was performed in 62.5% of cases, gamma knife surgery (GKS) in 18.7%; in 12.5% it was not carried out, while in one case there was no data available. Absence of recurrence was documented in 50% of patients, recurrence that required further treatments in 25%, while in 25% there was no data available.

CONCLUSIONS

Primary sellar neuroblastoma is an extremely rare entity with high propensity to recur; whole body scintigraphy is recommended to search for extracranial locations, for optimum management of the disease. Special attention should be paid to endocrinological evaluation and management.

[Primary sellar neuroblastoma (clinical case and literature review)]

Neuroblastoma is a malignancy developing from the embryonic neuroblasts of sympathetic nervous system. Primary sellar neuroblastomas are extremely rare (there are currently only 11 case reports in the literature). Possible development of neuroblastoma in sellar region expands differential diagnosis of local processes due to inclusion of neuroblastoma into the spectrum of suspected tumors. We report a literature review and description of a patient with primary sellar neuroblastoma.

Hypothalamic Endocrine Tumors: An Update

The hypothalamus is the site of synthesis and secretion of a number of endocrine peptides that are involved in the regulation of hormonal activity of the pituitary and other endocrine targets. Tumors of the hypothalamus have been recognized to have both structural and functional effects including hormone hypersecretion. The classification of these tumors has advanced over the last few years, and biomarkers are now available to classify these tumors and provide accurate structure-function correlations. This review provides an overview of tumors in this region that is critical to metabolic homeostasis with a focus on advances in the diagnosis of gangliocytomas, neurocytomas, and pituicytomas that are unique to this region.

Sellar Embryonal Tumor: A Case Report and Review of the Literature

Primitive neuroectodermal tumors (PNETs) are aggressive, poorly differentiated tumors in children and young adults. However, the embryonal tumor group did not include the central nervous system (CNS) PNET title and ependymoblastoma subtitle in the 2016 World Health Organization CNS tumor classification. Here, we report the case of a 6-year-old boy with a sellar embryonal tumor and present a review of the related literature. To the best of our knowledge, this is the first case of an endoscopically operated sellar embryonal tumor in the pediatric age group.

Early Stage olfactory neuroblastoma and the impact of resecting dura and olfactory bulb

OBJECTIVE

Compare outcomes of patients with olfactory neuroblastoma (ONB) without skull base involvement treated with and without resection of the dura and olfactory bulb.

METHODS

Retrospective review of ONB patients treated from 1992 to 2013 at the MD Anderson Cancer Center (The University of Texas, Houston, Texas, U.S.A.). Primary outcomes were overall and disease-free survival.

RESULTS

Thirty-five patients were identified. Most patients had Kadish A/B. tumors (97%), Hyams grade 2 (70%), with unilateral involvement (91%), and arising from the nasal cavity (68%). Tumor involved the mucosa abutting the skull base in 42% of patients. Twenty-five patients (71%) received surgery and radiation, whereas the remainder had surgery alone. Five patients (14%) had bony skull base resection, and eight patients (23%) had resection of bony skull base, dura, and olfactory bulb. Surgical margins were grossly positive in one patient (3%) and microscopically positive in four patients (12%). The 5- and 10-year overall survival were 93% and 81%, respectively. The 5- and 10-year disease-free survival (DFS) were 89% and 78%, respectively. Bony cribriform plate resection was associated with better DFS (P = 0.05), but dura and olfactory bulb resection was not (P = 0.11). There was a trend toward improved DFS in patients with negative resection margins (P = 0.19). Surgical modality (open vs. endoscopic) and postoperative radiotherapy did not impact DFS.

CONCLUSION

Most Kadish A/B ONB tumors have low Hyams grade, unilateral involvement, and favorable survival outcomes. Resection of the dura and olfactory bulb is not oncologically advantageous in patients without skull base involvement who are surgically treated with negative resection margins and cribriform resection.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1274-1280, 2018.

Ectopic primary olfactory neuroblastoma of the maxillary sinus

Olfactory neuroblastoma (ONB) is a rare malignant tumor. Although the vast majority of cases arise in the nasal cavity, ONB is rarely reported in ectopic locations. We report a case of ONB in the maxillary sinus. A 63-year-old woman presented with left-sided nasal obstruction and epistaxis. Magnetic resonance imaging showed a nonenhancing left maxillary sinus tumor. Histologic sections showed ONB, Hyams grade IV, invading bone, skeletal muscle, and adjacent fibroadipose tissue. It is essential to be accurate when diagnosing sinonasal tumors because the differential diagnosis is broad, and one must consider the possibility of ectopic ONB, although it is rare. The behavior of ONB and other neuroendocrine tumors of the sinonasal region is quite different, and there are varied approaches to treatment. Therefore, an accurate diagnosis as well as correct grade and stage must be assigned.

Possible esthesioneuroblastoma metastasis to paranasal sinuses: Clinical report and literature review

BACKGROUND

Local recurrence, and regional and distant metastases, respectively, develop in 30% and 15% of patients with esthesioneuroblastoma (ENB).

METHODS

This case report includes 3 patients with unusual recurrences of ENB in the sinonasal tract.

RESULTS

Patient 1 developed ENB in the bilateral maxillary sinuses after unilateral endoscopic resection of a left ENB followed by postoperative proton radiotherapy. Patient 2 developed ENB at the left optic-carotid recess 7 years after a craniofacial resection and postoperative radiotherapy. Patient 3 developed ENB over the left zygomatic process of the maxilla 4 years after a cranioendoscopic resection and postoperative radiation therapy for ENB of the ethmoid sinuses with intracranial extension. The possibility of venous tumor emboli must be considered as a likely etiology. However, alternative explanations include the development of a second primary or potential transformation because of tumor signaling.

CONCLUSION

We present 3 cases that may represent metastasis of ENB within the sinonasal tract.

Primary Sellar Neuroblastoma in an Elderly Patient: Case Report

A 71-year-old male presented with an isolated well-enhanced sellar lesion accompanied by hypopituitarism, diagnosed preoperatively as a pituitary adenoma, meningioma, or metastatic brain tumor. However, histological examinations yielded a diagnosis of neuroblastoma. Primary sellar neuroblastoma in the elderly is very rare. We therefore describe this case of primary sellar neuroblastoma, mimicking common pituitary tumor, and review the literature. There have so far been only nine reported cases of primary sellar neuroblastoma in the English literature. All reports like the present case, demonstrated similar neuroimaging of a “dumbbell-shaped extension in the sellar region.” Moreover, the tumors may exhibit characteristic features, such as rapid tumor growth, hypopituitarism, or oculomotor nerve palsy, and these findings may represent helpful signs for the diagnosis of primary sellar neuroblastoma.

Synchronous esthesioneuroblastoma and growth-hormone-secreting pituitary macroadenoma: combined open and endoscopic management

Background Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from the olfactory neuroepithelium. In this article we report a case of esthesioneuroblastoma presenting concomitantly with a growth-hormone (GH)-secreting pituitary macroadenoma. Results A 52 year old woman underwent surgery for suspected nasal polyps. Intralesional debulking of an intranasal tumor disclosed a low-grade esthesioneuroblastoma. Magnetic resonance imaging (MRI) demonstrated a large nasal and intracranial tumor, in addition to a separate sellar and suprasellar tumor. The patient was frankly acromegalic. She underwent a first-stage gross total resection of the esthesioneuroblastoma via a combined extended subfrontal and extended endonasal approach, followed by focused radiation therapy. She then returned for endoscopic removal of the GH-secreting pituitary macroadenoma. Conclusion The combined open and endoscopic management of this patient is described and a review of the literature presented. To our knowledge this is the first case of synchronous esthesioneuroblastoma and macroadenoma, in this case GH secreting, described in the literature.

Of mice and men: olfactory neuroblastoma among animals and humans

Olfactory neuroblastoma (ONB) is a rare tumour of nasal cavity and paranasal sinuses that arises from the olfactory neuroepithelium and has unpredictable clinical course. As the sense of smell is phylogenetically one of the first senses and olfactory neuroepithelium is evolutionary conserved with striking similarities among different species, we performed an extensive analysis of the literature in order to evaluate the similarities and differences between animals and humans on the clinical, morphological, immunohistochemical, ultrastructural and molecular level. Our analysis revealed that ONB was reported mainly in mammals and showed striking similarities to human ONB. These observations provide rationale for introduction of therapy modalities used in humans into the veterinary medicine. Animal models of neuroblastoma should be considered for the preclinical studies evaluating novel therapies for ONB.

"Leiomyomatoid angiomatous neuroendocrine tumor" (LANT) of the pituitary reflects idiosyncratic angiogenesis in adenomas of the gonadotroph cell lineage

Based on a single-case observation, the descriptive label "leiomyomatoid angiomatous neuroendocrine tumor" (LANT) has been tentatively applied to what was perceived as a possible novel type of dual-lineage pituitary neoplasm with biphasic architecture. We report on two additional examples of an analogous phenomenon encountered in male patients, aged 59 years (Case 1) and 91 years (Case 2). Both tumors were intra- and suprasellar masses, measuring 5.6 cm × 4.4 cm × 3.4 cm, and 2.7 cm × 2 cm × 1.7 cm, respectively. Histologically, Case 1 was an FSH-cell adenoma interwoven by vascularized connective tissue septa that tended to exhibit incremental stages of adventitial overgrowth. The epithelial component of Case 2 corresponded to an LH-cell adenoma, and lay partitioned by a maze of paucicellular to hyalinized vascular axes. Irrespective of architectural variations, perivascular spindle cells exhibited immunopositivity for vimentin, muscular actin, and smooth muscle actin. Conversely, negative results were obtained for CD34, EMA, S100 protein, GFAP, and TTF-1. Ultrastructural study failed to reveal metaplastic cell forms involving transitional features between adenohypophyseal-epithelial and mesenchymal-contractile phenotype. We propose that LANT be regarded as a peculiar reflection of maladaptive angiogenesis in some pituitary adenomas, rather than a genuine hybrid neoplasm. While no mechanistic clue is forthcoming to account for this distinctive pattern, hemodynamic strain through direct arterial - rather than portal - supply of the adenoma's capillary bed may be one such explanatory factor. The apparent predilection of the LANT pattern for macroadenomas of the gonadotroph cell lineage remains unexplained.

Low-Grade Esthesioneuroblastoma Presenting as SIADH: A Review of Atypical Manifestations

Esthesioneuroblastoma (ENB) is a neuroendocrine tumor that typically manifests as advanced stage malignancy in the superior nasal cavity. The hallmark symptoms include nasal obstruction and epistaxis, which result from local tissue invasion. Atypical clinical features can also arise and must be considered when diagnosing and treating ENB. These can include origin in an ectopic location, unusual presenting symptoms, and associated paraneoplastic syndromes. The case described here reports a nasal cavity ENB with atypical clinical features that occurred in a young female. Her tumor was low grade, appeared to arise primarily from the middle nasal cavity, and presented as syndrome of inappropriate antidiuretic hormone (SIADH). She also became pregnant shortly after diagnosis, which had implications on her surgical management. We review the atypical features that uncommonly occur with ENB and the clinical considerations that arise from these unusual characteristics.

Primary sellar neuroblastoma. A new case and review of literature

The primary intracranial development of olfactory neuroblastomas, outside olfactory epithelium, is rare. We report a case of primary sellar neuroblastoma without any aggressive histopathological features, managed solely surgically without adjuvant therapy, with good outcomes at 3 years. Primary sellar neuroblastomas mostly occur in women in the 4th decade with a context of a non-secreting pituitary tumour. Diagnosis is made on histopathological examination (small cells, fibrillary intercellular background, strong immunoreactivity for neurons markers, negative immunoreactivity for anterior pituitary hormones). Management is based on surgery. Adjuvant treatment is not consensual, largely depends on patient's conditions and aggressive histopathological features.

Primary sellar neuroblastoma presenting with syndrome of inappropriate secretion of anti-diuretic hormone

A 29-year-old Ethiopian man presented with marked bilateral visual loss, headache, hypopituitarism and significant hyponatraemia (115 mmol/L). A brain MRI scan demonstrated a large, lobulated, sellar and suprasellar mass, elevating the floor of the 3rd ventricle and compressing the optic chiasm. The patient underwent a transphenoidal resection of the mass followed by a craniotomy 10 days later. Histological examination demonstrated a Hyams' grade III neuroblastoma with ectopic expression of vasopressin. He underwent fractionated radiotherapy at a dose of 60 Gy in 30 fractions. Fourteen months after the onset, he is well with no neuroimaging evidence of tumour recurrence. His serum and urine sodium are completely normalised.

Ectopic olfactory neuroblastoma: report of four cases and a review of the literature

Our objective is to present a short series of four rare cases of ectopic olfactory neuroblastoma. Our methods present four case reports of ectopic olfactory neuroblastoma and a review of the literature for management and treatment of this disease. The results indicate short case series reports of ectopic olfactory neuroblastoma arising from the anterior ethmoidal sinuses, the nasopharynx, the lateral nasal wall and the floor of the nose. The discussion focuses on likely origins of ectopic olfactory neuroblastoma, its clinical features and management. We conclude that ectopic olfactory neuroblastoma is a rare disease. Treatment principles are the same for non-ectopic disease and guided by extension into adjacent structures such as the orbit or anterior cranial fossa and usually involves surgery with or without adjuvant radiotherapy.

Posttreatment prognosis of patients with esthesioneuroblastoma

OBJECT

There is no Class I evidence to guide the appropriate management of esthesioneuroblastoma (EN). Most data currently guiding treatment come from small- or modest-sized series gathered at individual centers that have concluded that surgery with radiotherapy is the preferred treatment. In this study, the authors summarize the published literature on treatment outcomes in patients with EN. The objective was to ascertain what variables predict prognosis in these patients and to determine the relative effect of different therapies.

METHODS

The authors identified 205 published studies containing treatment outcomes for surgery, radiotherapy, chemotherapy, or multimodal treatment. Using Kaplan-Meier analysis, the survival of patients who received surgery was compared with that in those who received surgery and radiotherapy. Additionally, Kadish staging was compared with low- and high-grade Hyams criteria to assess for subgroup prognostic significance in survival differences.

RESULTS

Nine hundred fifty-six patients met the inclusion criteria, with a median follow-up time of 3 years. Kaplan-Meier analysis demonstrated no difference in survival between patients who underwent surgery alone and those who underwent surgery plus radiotherapy at 5 years (78 vs 75%) or 10 years (67 vs 61%, respectively) (p = 0.3). Univariate analysis demonstrated worse survival in cases involving Kadish Grade C tumors, Hyams Grade 3 and 4 tumors, and in patients older than 65 years of age. Multivariate analysis demonstrated that Hyams Grade 3 and 4 lesions carried significant risk (proportional hazard = 4.83, p < 0.001) with 5- and 10-year survival of 47 and 31%.

CONCLUSIONS

A biopsy should always be obtained in cases suspected of EN because histology is a strong prognostic indicator and will help guide appropriate treatment. Unimodal surgery and combined surgery/radiotherapy appear to be of equivalent efficacy with respect to survival in patients with EN. Chemotherapy should be considered in high-grade EN.

Olfactory neuroblastoma: a review and update

Olfactory neuroblastoma (ONB) is a malignant neuroectodermal tumor that typically occurs in the superior nasal cavity. It is a distinct entity with features that include nesting, low-grade stippled nuclei, and neurofibrillary stroma with formation of pseudorosettes. It has a distinctive immunoprofile that includes keratin negativity, neuroendocrine marker positivity, and S100 positive sustentacular cells, which surround the nests of tumor in a supportive manner. Although the typical clinicopathologic features leave little room for misinterpretation, the wide variability in this tumor may cause diagnostic difficulty. This includes immunophenotypic diversity or patchy staining with immunomarkers, wide spectrum of grade and histology, posttreatment changes, and occasional divergent differentiation. In addition, problems in sampling, preservation, and clinical localization may make the diagnosis more challenging. A large group of tumors may show morphologic overlap with ONB, with some mimicking low-grade tumors, whereas others mimic high-grade tumors. This differential diagnosis has important treatment and prognostic implications. Further complicating the issue is that many of the mimics themselves may show great morphologic and immunophenotypic variability. This manuscript will review the typical clinical and pathologic features of ONB, address the great variability of ONB in our experience, will focus on the differential diagnosis and report on recent findings in these tumors including molecular genetics where applicable.

Sinonasal malignancies of neuroendocrine origin

The sinonasal malignancies of putative neuroendocrine origin-esthesioneuroblastoma, sinonasal neuroendocrine carcinoma, sinonasal undifferentiated carcinoma, and sinonasal small cell carcinoma-are uncommon malignancies that frequently present with locally advanced disease. Pathologic distinction between these entities can be difficult, but is important to guide management. These malignancies require complex multimodality treatment and are best managed by multidisciplinary teams in major centers that have expertise in sinonasal malignancies.

A primary sellar esthesioneuroblastomas with unusual presentations: a case report and reviews of literatures

The development of an esthesioneuroblastoma outside to the region in which olfactory epithelium exists is extremely rare. Only nine cases were reported in the previous literatures. The author presents a 40 years-old man with ectopic esthesioneuroblastoma in sella turcica. In contrast to the previous nine cases, our case presented unusual presentations-CSF rhinorrhea and meningitis. Endoscopic transphenoid approach with removal of tumor and repair of dura defect followed by radiotherapy offered a good result in this case. Moreover, differential diagnosis and the origin of the ectopic esthsioneuroblastoma would be discussed.

Endoscopic-assisted excision of esthesioneuroblastoma

The purpose of this article is to report a case of esthesioneuroblastoma involving the bilateral paranasal sinuses, which was excised using an endoscopic-assisted transfacial approach. A patient presented with nasal swelling and left-sided nasal obstruction, epistaxis, and diplopia. Examination revealed broadening of the nasal dorsum with a fleshy pink mass in both nasal cavities. Computed tomographic scan showed a mass involving the nasal cavity and paranasal sinuses on both sides. The tumor was diagnosed as group C esthesioneuroblastoma. The mass was excised by bilateral medial maxillectomy and bilateral frontoethmoidectomy. Using a 0 degrees endoscope, the attachment of the tumor to the cribriform plate was identified and resected using a motordrill. On Waroff staining, Hispathology slides suggested esthesioneuroblastoma. The patient was asymptomatic for 1 year, following which he developed infection of the nasal cavity for which he had no form of treatment. He subsequently developed maggots in the nasal cavity after which he died. An endoscopic resection of the cribriform plate from the nasal cavity without a formal craniofacial resection can be safely performed with oncologic safety.

Primary olfactory neuroblastoma originating from the inferior meatus of the nasal cavity

Olfactory neuroblastoma is a rare malignant tumor of the nasal cavity arising from the olfactory neuroepithelium. It usually presents as a polypoid mass high in the nasal vault including the cribriform plate, superior turbinate, and superior portion of nasal septum. An 89-year-old man visited our office with symptoms of occasional left nasal bleeding and obstruction. On the endoscopic examinations, polypoid mass with bleeding tendency was observed in the left inferior meatus. Biopsy was performed, and the diagnosis of olfactory neuroblastoma was confirmed by histopathologic examination and immunohistochemical staining. The tumor was resected via medial maxillectomy, and the final pathologic report established that it was primary olfactory neuroblastoma that occurred from the inferior meatus. In this report, a literature review was performed on the pathologic characteristics and prognosis of the tumor, and possible hypotheses that olfactory neuroblastoma has originated from the inferior meatus were discussed.