Olfactory neuroblastoma causing ectopic ACTH syndrome

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.

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.

Adrenocorticotropic Hormone-Secreting Esthesioneuroblastoma with Ectopic Cushing's Syndrome

Esthesioneuroblastoma as a source of ectopic Cushing's syndrome is rare, and to the best of our knowledge, only 20 cases have been reported worldwide. A 46-year-old healthy man visited a local clinic for general weakness and hyposmia, and underwent examination with serial endocrinological workup and brain imaging. ⁶⁸Gallium-DOTA-TOC positron emission tomography scan was helpful where diagnosis of sellar MRI and inferior petrosal sinus sampling were discordant. Combined transcranial and endoscopic endonasal approach surgery was performed, and a diagnosis of esthesioneuroblastoma was given.

Adrenocorticotropic Hormone-Dependent Cushing Syndrome Caused by an Olfactory Neuroblastoma

Olfactory neuroblastoma (ONB) is an unusual malignant neoplasm originating from the olfactory neuroepithelium. Secretion of adrenocorticotropic hormone (ACTH) from this tumor has been exceptionally reported. We describe a young man with resistant hypertension and a cushingoid phenotype. After hormonal confirmation of an ACTH-dependent Cushing syndrome, non-invasive dynamic tests were carried out to evaluate the cause of the ACTH source. Plasma cortisol decrease after a high-dose dexamethasone suppression test and cortisol increase after a desmopressin (DDAVP) stimulation test suggested a Cushing disease. A magnetic resonance image (MRI) of the brain and an Indium-111 octreotide scan revealed a large mass centered in the sphenoid sinus with lateral and posterior extension. An ACTH secreting ONB was confirmed with a trasnasal biopsy. Patient was offered a combined therapy with surgical resection and radiotherapy but refused surgery. The neoplasm was treated with neoadjuvant cisplatin-based chemotherapy followed by fractionated radiotherapy. Hypercortisolism initially improved with metyrapone but normocortisolism was only achieved after local control of the tumor with radiotherapy. Clinical presentation of ONB is usually related to local symptoms (as nasal obstruction and epistaxis) dependent on its ubication and extension. Cushing syndrome from ACTH production is a rare manifestation of ONB. This case also underlies the difficulties related to the interpretation of dynamic endocrine tests in Cushing syndrome.

Pituitary Adenomas Presenting as Sinonasal or Nasopharyngeal Masses: A Case Series Illustrating Potential Diagnostic Pitfalls

We present a series of nonectopic pituitary adenomas presenting as polypoid sinonasal or nasopharyngeal masses. Thirteen cases diagnosed by biopsies from the nasal cavity, sinuses, or nasopharynx were identified from a series of 1288 surgical pituitary specimens. The patients included 5 men and 8 women ranging from 29 to 69 years of age. The presentations included nasal obstruction (4 cases), headaches (3), visual defects (2), recurrent nose bleeds (1), rhinorrhea (1), sepsis (1), fatigue (1), and hyperthyroidism (1). All patients had large tumors involving the sella and extending inferiorly to involve the sphenoid sinus in 10 cases, ethmoid in 8, nasopharynx in 3, nasal cavity in 6, maxillary and frontal sinuses in 1 case each. In 3 patients, the biopsy was from the nasopharynx, in 4 from the nasal cavity, in 4 from the sphenoid sinus, and in 2 from the ethmoid sinus. The correct diagnosis of pituitary adenoma was initially made in 10 cases. In 3 cases the initial diagnosis was incorrect; 2 tumors were classified as olfactory neuroblastoma, one of those was reclassified as neuroendocrine carcinoma, and 1 case was initially diagnosed as neuroendocrine carcinoma with aberrant adrenocorticotrophic hormone expression. Clinical follow-up (2 to 25 y) and treatment information was available in 10 cases. All 10 patients were alive, either free of disease (4 cases) or with disease (6 cases). In 2 cases, the wrong diagnoses led to incorrect treatment with significant morbidity. These cases illustrate that pituitary adenomas can invade nasopharynx and sinonasal cavities and when they do, they present a possible diagnostic pitfall with potentially serious consequences. We demonstrate the need to always consider this entity when encountering a nasopharyngeal or sinonasal tumor with neuroendocrine features.

Intraoperative hypertensive crisis due to a catecholamine-secreting esthesioneuroblastoma

BACKGROUND

Although uncommon, esthesioneuroblastomas may produce clinically significant amounts of catecholamines.

METHODS

We report a patient with a catecholamine-secreting esthesioneuroblastoma who developed an intraoperative hypertensive crisis.

RESULTS

A patient with a history of hypertension was referred to our skull base center for management of a residual esthesioneuroblastoma. A staged endonasal endoscopic approach was planned. At the conclusion of the first stage, a hypertensive crisis occurred. Workup revealed elevated levels of serum and urinary catecholamines. The patient was treated with alpha adrenoceptor blockade before the second stage. Serum catecholamine levels after this second stage were normal. On immunohistochemical analysis, the tumor cells were found to be positive for tyrosine hydroxylase, the rate limiting enzyme in catecholamine synthesis, and achaete-scute homologue 1, a transcription factor essential in the development of olfactory and sympathetic neurons.

CONCLUSION

Catecholamine production should be considered in the differential of unexpected extreme hypertension during surgical resection of esthesioneuroblastoma.

Paraneoplastic syndromes in olfactory neuroblastoma

Olfactory neuroblastoma (ONB) is a rare malignant neoplasm of sinonasal tract, derived from olfactory epithelium. Unilateral nasal obstruction, epistaxis, sinusitis, and headaches are common symptoms. Olfactory neuroblastoma shows neuroendocrine differentiation and similarly to other neuroendocrine tumors can produce several types of peptic substances and hormones. Excess production of these substances can be responsible for different types of endocrinological paraneoplastic syndromes (PNS). Moreover, besides endocrinological, in ONB may also occur neurological PNS, caused by immune cross-reactivity between tumor and normal host tissues in the nervous system. Paraneoplastic syndromes in ONB include: syndrome of inappropriate ADH secretion (SIADH), ectopic ACTH syndrome (EAS), humoral hypercalcemia of malignancy (HHM), hypertension due to catecholamine secretion by tumor, opsoclonus-myoclonus-ataxia (OMA) and paraneoplastic cerebellar degeneration. Paraneoplastic syndromes in ONB tend to have atypical features, therefore diagnosis may be difficult. In this review, we described initial symptoms, patterns of presentation, treatment and outcome of paraneoplastic syndromes in ONB, reported in the literature.

Nasally located ectopic ACTH-secreting pituitary adenoma (EAPA) causing Nelson's syndrome: diagnostic challenges

PURPOSE

We report the first case of an Ectopic adrenocorticotrophin (ACTH)-secreting pituitary adenoma (EAPA) located within the posterior nasal septum associated with Nelson's syndrome, which eluded diagnosis for over a decade. In this report, we explore the reasons for such diagnostic difficulty and suggest ways in which an earlier diagnosis may be made.

METHODS AND RESULTS

A 19 years old Lebanese man presented in 2000, with overt Cushing's syndrome confirmed with markedly elevated urine free cortisols and failed dexamethasone suppression tests. An unsuppressed ACTH and a possible 5 mm adenoma on MRI (Magnetic Resonance Imaging) pituitary suggested Cushing's disease. The patient underwent trans-sphenoidal surgery (TSS), but histology revealed normal pituitary tissue and Cushing's syndrome persisted. A repeat MRI pituitary showed no anomaly, and extensive investigations failed to locate an ectopic lesion. Subsequently a bilateral adrenalectomy was performed. Over the ensuing years, the patient developed Nelson's syndrome with hyperpigmentation and markedly elevated ACTH levels. Repeated high dose dexamethasone suppression tests, corticotrophin releasing hormone (CRH) tests, and CRH stimulated inferior petrosal sinus samplings (IPSS) suggested a pituitary origin of the ACTH. Two further TSS were unsuccessful. The pituitary was irradiated. Subsequent review of his previous MRIs revealed an enlarging mass within the posterior nasal septum, which was excised in 2011. The histology confirmed the diagnosis of an EAPA within the nasal septum.

CONCLUSION

Ectopic ACTH-secreting pituitary adenomas can occur not only along the developmental route of Rathke's pouch, but other aberrant locations giving a clinical and biochemical picture identical to Cushing's disease or Nelson's syndrome. Clinicians should suspect an EAPA, when a central ACTH source seems to be apparent with no obvious pituitary adenoma. A detailed MRI involving possible EAPA sites aids in locating these unusual lesions.

Hypercortisolaemia due to ectopic adrenocorticotropic hormone secretion by a nasal paraganglioma: a case report and review of the literature

BACKGROUND

Adrenocorticotropic hormone-producing extraadrenal paragangliomas are extremely rare. We present a case of severe hypercortisolemia due to ectopic adrenocorticotropic hormone secretion by a nasal paraganglioma.

CASE PRESENTATION

A 70-year-old Caucasian woman, was emergently admitted to our department with supraventricular tachycardia, oedema of face and extremities and hypertensive crisis. Initial laboratory evaluation revealed severe hypokalemia and hyperglycemia without ketoacidosis, although no diabetes mellitus was previously known. Computed tomography revealed a large tumor obliterating the left paranasal sinus and a left-sided adrenal mass. After cardiovascular stabilisation, a thorough hormonal assessment was performed revealing marked adrenocorticotropic hormone-dependent hypercortisolism. Due to the presence of a cardiac pacemaker magnetic resonance imaging of the hypophysis was not possible. [68Ga-DOTA]-TATE-Positron-Emission-Tomography was performed, showing somatostatin-receptor expression of the paranasal lesion but not of the adrenal lesion or the hypophysis. The paranasal tumor was resected and found to be an adrenocorticotropic hormone-producing paraganglioma of low-proliferative rate. Postoperatively the patient became normokaliaemic, normoglycemic and normotensive without further need for medication. Genetic testing showed no mutation of the succinatdehydrogenase subunit B- and D genes, thus excluding hereditary paragangliosis.

CONCLUSION

Detection of the adrenocorticotropic hormone source in Cushing's syndrome can prove extremely challenging, especially when commonly used imaging modalities are unavailable or inconclusive. The present case was further complicated by the simultaneous detection of two tumorous lesions of initially unclear biochemical behaviour. In such cases, novel diagnostic tools - such as somatostatin-receptor imaging - can prove useful in localising hormonally active neuroendocrine tissue. The clinical aspects of the case are discussed and relevant literature is reviewed.

Bilateral adrenalectomy: lifesaving procedure in severe Cushing syndrome

OBJECTIVE

To discuss the role of bilateral adrenalectomy in Cushing syndrome, as illustrated in a case of severe hypercortisolism that was unresponsive to combination agent medical therapy.

METHODS

We report the clinical, laboratory, imaging, and pathologic findings in a patient with ectopic Cushing syndrome attributable to an adrenocorticotropic hormone (ACTH)-secreting neuroblastoma. In addition, we provide a literature review regarding olfactory neuroblastoma and discuss current and emerging therapeutic options for Cushing syndrome.

RESULTS

A 59-year-old man presented with nasal congestion and neck swelling and was noted to have hypokalemia, hypertension, and hyperglycemia. A nasal biopsy demonstrated a poorly differentiated carcinoma with neuroendocrine features. He was subsequently diagnosed as having ACTH-dependent Cushing syndrome, but despite high-dose combination medical therapy, his condition rapidly deteriorated. Urgent bilateral adrenalectomy provided rapid control of the hypercortisolism, and the patient was later able to undergo an uncomplicated total macroscopic resection of his locally metastatic primary tumor.

CONCLUSION

This report describes the challenges in the diagnosis and management of ACTH-dependent Cushing syndrome and highlights the important role that bilateral adrenalectomy can still have in patients with severe hypercortisolism causing life-threatening complications.

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.

[Diagnostic difficulties of the patient with sinonasal tract tumor; therapeutic dilemmas - a case report and up to date review]

Esthesioneuroblastoma (ENB) is a rare malignancy unique to the sinonasal tract. It arises from the olfactory epithelium and has a tendency to originate from one side of the nasal cavity and paranasal sinuses with frequent extension into the cranial cavity and orbit. There is a bimodal age distribution between 11 and 20 years and between 51 and 60 years. ENB accounts for approximately 2-3% of intranasal cancers. Due to the non-specific nature of the initial presentation and slow growth of the tumor, patients often have a long history before diagnosis. Physicians including pathologists are not always aware of distinctive features of ENB especially radiographic, histologic and immunohistochemical characteristics. Additional difficulty can be the fact that Esthesioneuroblastoma can histologically mimic many tumors within the sinonasal tract. We report on a 38-year-old male patient with a Kadish stage C tumor with frontal lobe invasion. The patient underwent a craniofacial resection with a combined head neck and neurosurgeon team. After the surgery postoperative radiotherapy was used. The aim of this study is to present the natural history of the malignancy, the diagnostic process, treatment and prognosis, based on the literature review.

Metastatic esthesioneuroblastoma secreting adrenocorticotropic hormone in pediatric patients

The purpose of this article was to report a pediatric case of secondary cervical esthesioneuroblastoma involving the parapharyngeal lymph nodes. A 3-year-old boy came to our clinical observation because of a right lymphonodal mass evidenced by nuclear magnetic resonance and a diagnosis of Cushing syndrome associated with ectopic adrenocorticotropic hormone secretion, moon face, central obesity, asthenia, and hirsutism. At the age of 10 months, the patient underwent endoscopic surgery for asportation of the World Health Organization stage IV esthesioneuroblastoma. At 38 months of age, the patient underwent right parapharyngeal lymphadenectomy with surgical access by a double mandibulectomy. After surgery, serum ACTH, cortisolemia, and urinary excretion of cortisol were within the reference range. Blood pressure was recorded at 110/70 mm Hg. Moon face disappeared, as well as central obesity and hirsutism. Clinical report is presented together with brief review of literature.

Cushing's Syndrome: An Unusual Presentation of Olfactory Neuroblastoma

A 48-year-old man presented with symptoms consistent with Cushing's syndrome. Subsequent laboratory studies revealed markedly elevated adrenocorticotropic (ACTH) and cortisol levels, as well as a hypoklemic metabolic alkalosis. A pituitary MRI was performed, which revealed a normal pituitary; however, a large mass was seen centered in the ethmoid and paranasal sinuses with a significant amount of extension into surrounding structures. A biopsy was performed and pathology of the specimen was consistent with esthesioneuroblastoma. Immunohistochemical staining further defined the tumor as an ACTH-secreting esthesioneuroblastoma. After total resection of the mass and further treatment with adjuvant radiation therapy, the patient's symtoms completely resolved and the ACTH and cortisol levels were also greatly reduced. This case demonstrates the successful diagnosis and treatment of a rare neoplasm. Ectopic ACTH syndrome due to esthesioneuroblastoma is extremely uncommon with only five other cases being discussed in the literature.

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.

Esthesioneuroblastoma (Olfactory Neuroblastoma) with Ectopic ACTH Syndrome: a multidisciplinary case presentation from the Joan Karnell cancer center of Pennsylvania Hospital

The case of a patient with recurrent esthesioneuroblastoma complicated by ectopic adrenocorticotropic hormone production is presented, including the workup and management of this uncommon complication of an uncommon disease.

Clinical features and management of ectopic ACTH syndrome at a single institute in Japan

Ectopic ACTH syndrome (EAS) is a diagnostic challenge because it is often indistinguishable from Cushing's disease. We describe our series of EAS patients referred to us during 1992-2009. Among 16 cases (9 females / 7 males), with mean age of 58.4 ± 19.0yr, the ectopic source was identified in ten (proven EAS), whereas unidentified in six (occult/unknown EAS). Their salient clinical manifestations included Cushingoid feature (88%), skin pigmentation (88%), profound hypokalemia (88%), hypertension (75%), diabetes/impaired glucose tolerance (75%), hyperlipidemia (69%), and severe infection (44%). Dynamic endocrine tests revealed markedly elevated plasma ACTH levels (211 ± 116pg/mL) and cortisol levels (60.9 ± 30.1µg/dL) which showed resistance to overnight high-dose (8mg) dexamethasone suppression test in 15 (94%) and unresponsiveness to CRH stimulation in 12 (75%). No ACTH gradient during inferior petrosal sampling was noted in 13 of 15 (87%). Imaging tests by CT/MRI identified the tumors in 8 of 16 (50%), in 4 of 11 (36%) and 4 of 6 (66.7%) octreotide-responders by somatostatin receptor scintigraphy, but in only one of 9 (11.1%) by FDG-PET scan. Six cases deceased, including small cell carcinoma (2) and adenocarcinoma (1) of lung, neuroendocrine carcinoma of pancreas (1) and stomach (1), and olfactory neuroblastoma (1), whereas 4 cases survived after removal of the tumors, including bronchial carcinoid tumor (3) and thymic hyperplasia (1). Six occult/unknown EAS patients survived for 67.5 months after medical treatment with metyrapone to control hypercortisolism. Thus, various endocrine tests combined with imaging studies are required to correctly localize the tumors. Control of hypercortisolemia by metyrapone, even if tumor is unrecognized, is critical for better prognosis, and the long-term follow-up by repeated endocrine and imaging tests is mandatory.

Location of ectopic adrenocortical hormone-secreting tumors causing Cushing's syndrome in the paranasal sinuses

BACKGROUND

The majority of ectopic adrenocorticotropic hormone (ACTH)-secreting tumors are localized in the chest or abdomen. Occasionally, these tumors are found in the paranasal sinuses.

METHODS

We present 2 unusual cases of ectopic ACTH syndrome whose ACTH-secreting tumors were localized in the paranasal sinuses and describe their biochemical and radiological presentation.

RESULTS

The first patient had an ACTH-secreting olphactory neuroblastoma originating in the ethmoid sinuses. The second patient had a clinical course and biochemical findings indistinguishable from pituitary ACTH-dependent Cushing's syndrome, except for negative petrosal sinus sampling. Head imaging showed a "polyp" in the left maxillary sinus-secreting ACTH. Both patients went into remission following surgical resection and recovered normal pituitary-adrenal axis function.

CONCLUSION

Ectopic ACTH secretion may originate from lesions in the paranasal sinuses. This accessible location allows for direct immunohistochemical diagnosis with ACTH staining. Surgical resection/radiation therapy can result in complete remission of the disease and restoration of normal pituitary-adrenal function.

Two cases of ectopic adrenocorticotropic hormone syndrome with olfactory neuroblastoma and literature review

Olfactory neuroblastomas are rare, slow-growing malignant tumors, usually diagnosed at advanced stages. Ectopic adrenocorticotropic hormone (ACTH) syndrome caused by an olfactory neuroblastoma is extremely rare. We reported two Korean women who suffered from ectopic ACTH syndrome (EAS) caused by olfactory neuroblastomas. The first patient was a 66-year-old woman who had been diagnosed as olfactory neuroblastoma and refused the management two years before and the second patient was a 37-year-old woman on chemotherapy for olfactory neuroblastoma. In the first case, she presented the Cushingoid appearance with systemic edema and her tumor was removed surgically. ACTH secretion by the tissue was confirmed by immunohistochemistry. By contrast, the second patient presented as severe pneumonia caused by cytomegalovirus and was treated with anti-viral agent followed by chemotherapy and radiotherapy, and her residual mass remained. However, after treatment, both patients' plasma ACTH and cortisol levels returned to normal without any adrenolytic therapy. Considering the causative tumors of EAS can be rarely cured and EAS increases the susceptibility to infections, it is prudent to suppress any hypercortisolemia initially, apart from treating the causal malignancy.

Esthesioneuroblastoma: a case report of diffuse subdural recurrence and review of recently published studies

Esthesioneuroblastoma is a rare malignancy arising from the olfactory epithelium. We present a case history of a 75-year-old man who presented with a Kadish stage C esthesioneuroblastoma and underwent craniofacial surgery and adjuvant radiotherapy. Two years later he was found to have diffuse subdural deposits with distant bone and nodal metastases, treated with further radiotherapy. The patient's condition subsequently deteriorated and he died. Given this unusual pattern of failure, we review the recent published studies regarding the natural history, treatment and outcome for this tumour.