Paraneoplastic syndromes in olfactory neuroblastoma

Update on olfactory neuroblastoma

Olfactory neuroblastomas are uncommon malignancies that arise from olfactory receptor cells located high in the nasal cavity. Accurate diagnosis plays a crucial role in determining clinical results and guiding treatment decisions. Diagnosis can be a major challenge for pathologists, especially when dealing with tumours with poor differentiation. The discovery of several molecular and immunohistochemical markers would help to overcome classification difficulties. Due to the paucity of large-scale studies, standardisation of diagnosis, treatment and prediction of outcome remains a challenge. Surgical resection by endoscopic techniques with the addition of postoperative irradiation is the treatment of choice. In addition, it is advisable to consider elective neck irradiation to minimise the risk of nodal recurrence. Molecular characterisation will help not only to make more accurate diagnoses but also to identify specific molecular targets that can be used to develop personalised treatment options tailored to each patient. The present review aims to summarise the current state of knowledge on histopathological diagnosis, the molecular biology and management of this disease.

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.

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.

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

OBJECTIVES

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

CASE PRESENTATION

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

CONCLUSIONS

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

A Rare Case of Ectopic Adrenocorticotropic Hormone Syndrome with Recurrent Olfactory Neuroblastoma

A 40-year-old woman who had a history of recurrent olfactory neuroblastoma presented with full moon face, central obesity, buffalo hump, impaired glucose tolerance and bilateral cervical lymph node swelling. Laboratory tests showed morbidly elevated levels of adrenocorticotropic hormone (ACTH) and cortisol, which were not suppressed by high-dose (8 mg) dexamethasone. Biopsies of the enlarged cervical lymph nodes revealed ACTH-positive metastatic olfactory neuroblastoma, and ectopic ACTH syndrome was diagnosed. Metyrapone was used to suppress cortisol production and resulted in decreased levels of ACTH and cortisol. Bilateral cervical tumor resection further reduced the ACTH and cortisol levels, accompanied by a reduction in the metyrapone dosage. Cushing's syndrome was alleviated through ACTH-producing tumor removal.

Isolated primary maxillary sinus esthesioneuroblastoma presenting as idiopathic syndrome of inappropriate antidiuretic hormone

Esthesioneuroblastoma is an uncommon tumour, and isolated primary involvement of the maxillary sinus is exceedingly rare. Esthesioneuroblastoma has infrequently been reported as a source of paraneoplastic ectopic hormone production. We report a case of isolated primary maxillary esthesioneuroblastoma, presenting as idiopathic syndrome of inappropriate antidiuretic hormone (SIADH). A 17-year-old girl presented with symptoms consistent with SIADH and no sino-nasal symptoms. MRI to exclude pituitary tumour revealed an isolated lesion of the right maxillary sinus. Biopsy demonstrated esthesioneuroblastoma. The lesion was removed endoscopically as a single en bloc specimen. Following resection, the sodium level returned to normal. This is only the third report in the literature of a primary maxillary esthesioneuroblastoma presenting as SIADH.

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.

Ectopic adrenocorticotropic hormone syndrome associated with olfactory neuroblastoma: acquirement of adrenocorticotropic hormone expression during disease course as shown by serial immunohistochemistry examinations

Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is a condition of endogenous hypercortisolism sustained by an extrapituitary ACTH-secreting tumor. Olfactory neuroblastoma (ONB) is a rare malignant neoplasm of the sinonasal tract and is derived from the olfactory epithelium. Because the paranasal sinus is not a common site of EAS, the development of ONB in patients with EAS is rare. We herein report the first known case of ONB with acquirement of ACTH production during the clinical course as proven by immunohistochemistry. A 50-year-old man diagnosed with ONB was referred to our department in July 2015 because of hypokalemia, hyperglycemia, decreased eosinophil and granulocyte counts, and elevated serum levels of ACTH and cortisol. Although two previous ONB biopsy specimens (2011 and 2014) showed no ACTH immunoreactivity, a newly obtained specimen in August 2015 clearly showed ACTH immunoreactivity. This is the first case of ectopic ACTH syndrome associated with an ONB that acquired the ability to express ACTH during its clinical course as shown by serial immunohistochemical examinations.

Pulmonary nocardiosis mimicking small cell lung cancer in ectopic ACTH syndrome associated with transformation of olfactory neuroblastoma: a case report

Background

Pulmonary nocardiosis frequently develops as an opportunistic infection in cell-mediated immunosuppressive patients, and sometimes requires differentiation from pulmonary malignancy. Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is a neoplastic disorder which leads to impaired cell-mediated immunity, and is commonly associated with small cell lung cancer (SCLC). Because pulmonary infection and causative malignancy can appear as pulmonary lesions with EAS, differentiation of these diseases remains a critical issue for physicians.

Case presentation

A 52-year-old woman with progressive lower limb paralysis and general fatigue was referred to us. She had been diagnosed with olfactory neuroblastoma (ONB) and treated with surgery and radiation therapy 10 years before the referral and had required stereotactic radiosurgery and chemotherapy 4 years later for a relapse of the ONB. On referral, she presented with Cushing’s syndrome with elevated cortisol and ACTH levels. Potassium supplement improved her symptoms; however, a month later, she was urgently hospitalized due to acute pleuritic chest pain on inspiration. Chest computed tomography revealed left lower lobular consolidations and a contralateral nodule in the right middle lobe. The clinical history and laboratory work-up suggested that her Cushing’s syndrome had most likely arisen from EAS. Additionally, the lungs were suspected as the ACTH source due to high levels of progastrin-releasing peptide and progressive pulmonary consolidation with a contralateral nodule, suggesting SCLC. However, histological examination from bronchoscopy revealed no evidence of malignancy, and Nocardia cyriacigeorgica was isolated from bronchoalveolar lavage fluid. Sulfamethoxazole/trimethoprim improved her pulmonary lesions. Somatostatin receptor scintigraphy revealed strong tracer uptake in the ONB lesions, indicating that the origin of the EAS was the olfactory tumor. However, histological examination of ONB specimens resected 10 years earlier showed no intracytoplasmic immunopositivity for ACTH.

Conclusions

We highlight a rare case of pulmonary nocardiosis, which was associated with EAS mimicking SCLC, and was related to ONB transformation. Nocardiosis has to be considered even though anamnestic, clinical, and radiological aspects suggest the presence of metastasis. Additionally, physicians should carefully monitor patients with ONB for the development of Cushing’s symptoms because the tumor can transform into an ACTH-producing form, even after long-term follow-up.

Ectopic Cushing's syndrome secondary to olfactory neuroblastoma

We present the case of a patient with Cushing's syndrome secondary to ectopic ACTH secretion. A MR of the head showed a left-sided nasal mass extending down from the cribriform plate. The patient underwent endoscopic resection with nearly complete removal of the mass. Histological examination showed an ACTH-secreting olfactory neuroblastoma (ONB). The patient's cortisol levels returned to normal range after surgery and have remained normal for over a year. ONB is a rare cause for ectopic ACTH secretion. This case highlights the diagnostic and management difficulties in patients with ectopic ACTH secretion, and provides a brief review of ONB.

An unusual manifestation of olfactory neuroblastoma

A 62-year-old woman presented with an 11-month history of worsening nasal symptoms of rhinorrhoea, anosmia, nasal congestion and intermittent epistaxis. MRI revealed a large mass in the upper nasal vault. Biopsy of the mass revealed an olfactory neuroblastoma. While waiting resection, she acutely developed severe proximal muscle weakness, lethargy and lower extremity oedema. Blood glucose was elevated, and hypokalaemic metabolic alkalosis was noted. Elevated serum cortisol level of 95.7 µg/dL (8.7-22.4 µg/dL) and markedly elevated 24-hour urinary cortisol level of 6962.3 µg/24 hours (4.0-50.0 µg/24 hours) with concurrent adrenocorticotropic hormone (ACTH) level of 171 pg/mL (6-58 pg/mL) were suggestive of an ACTH-dependent source of hypercortisolism. A subsequent positive high-dose dexamethasone suppression test was consistent with ectopic ACTH production. She underwent near-total resection of the right nasal mass followed by radiotherapy, resulting in complete resolution of signs and symptoms of cortisol excess.

Genetic and molecular alterations in olfactory neuroblastoma: implications for pathogenesis, prognosis and treatment

Olfactory neuroblastoma (ONB, Esthesioneuroblastoma) is an infrequent neoplasm of the head and neck area derived from olfactory neuroepithelium. Despite relatively good prognosis a subset of patients shows recurrence, progression and/or metastatic disease, which requires additional treatment. However, neither prognostic nor predictive factors are well specified. Thus, we performed a literature search for the currently available data on disturbances in molecular pathways, cytogenetic changes and results gained by next generation sequencing (NGS) approaches in ONB in order to gain an overview of genetic alterations which might be useful for treating patients with ONB. We present briefly ONB molecular pathogenesis and propose potential therapeutic targets and prognostic factors. Possible therapeutic targets in ONB include: receptor tyrosine kinases (c-kit, PDGFR-b, TrkB; EGFR); somatostatin receptor; FGF-FGFR1 signaling; Sonic hedgehog pathway; apoptosis-related pathways (Bcl-2, TRAIL) and neoangiogenesis (VEGF; KDR). Furthermore, we compare high- and low-grade ONB, and describe its frequent mimicker: sinonasal neuroendocrine carcinoma. ONB is often a therapeutic challenge, so our goal should be the implementation of acquired knowledge into clinical practice, especially at pretreated, recurrent and metastatic stages. Moreover, the multicenter molecular studies are needed to increase the amount of available data.