Carcinoid tumour of the middle ear. A morphological and immunohistochemical study with comments on histogenesis and differential diagnosis

Management and outcome of middle ear adenomatous neuroendocrine tumours: A systematic review

Middle ear adenomatous neuroendocrine tumours (MEANTs) are rare, unpredictable tumours. Although most MEANTs are characterized by a benign biological behaviour and indolent growth pattern, some studies have reported locally invasive and metastastic disease. Currently, the optimal management strategy for MEANTs remains subject of debate. The aim of this study is to review the literature on MEANTs with focus on its clinical characteristics, treatment strategies and outcome. A systematic review was conducted using PubMed, Embase and Cochrane databases. A total of 111 studies comprising 198 patients with MEANT were included. Treatment modalities comprised surgery (90%), surgery with adjuvant radiotherapy (9%) and palliative (chemo)radiotherapy in (1%). Local recurrence was observed in 25% of the patients and 7% of the patients developed metastasis, over a median period of 5.7 years (range 7 months - 32 years). Twelve of 13 patients (92%) who developed metastases had a local recurrence. Four patients (2%) died of MEANT: three due to distant metastases and one due to extensive local recurrence. Reliable histopathologic predictors of outcome could not be identified. These findings indicate that the clinical presentations of MEANT vary substantially, the overall recurrence rate is considerable and initial local tumour control is paramount. Because of the unpredictable clinical course, prolonged follow-up is warranted.

Middle ear adenoma with neuroendocrine differentiation: Report of a rare case

Middle ear adenoma with neuroendocrine differentiation (MEA-ND) is also called as neuroendocrine adenoma. Neuroendocrine tumors are rarely seen in the head and neck region and are even more rare in the middle ear. Clinical and radiological findings are non-specific and seldom suggest this diagnosis. Nomenclature and behavior of this tumor has been historically controversial. Both epithelial as well as neuroendocrine origin have been suggested. They comprise <2% of all ear tumors and commonly present with unilateral hearing loss, aural fullness, and tinnitus. We present a case report of MEA-ND in a 24-year-old woman who presented with heaviness and tinnitus in the right ear.

Neuroendocrine Adenoma of the Middle Ear: A Rare Histopathological Diagnosis

Neuroendocrine tumours occur throughout the body but are rare in the head and neck region and particularly rare in the middle ear. Clinical findings are often nonspecific and therefore pose a diagnostic challenge. Furthermore, the nomenclature of neuroendocrine tumours of the middle ear is historically controversial. Herein a case is presented of a middle ear adenoma in a 33-year-old patient who presented with otalgia, hearing loss, and facial nerve palsy. A brief discussion is included regarding the histopathological features of middle ear adenomas and seeks to clarify the correct nomenclature for these tumours.

Metastasizing middle ear carcinoid: an unusual case report, with focus on ultrastructural and immunohistochemical findings

BACKGROUND

There are only 4 unequivocal cases of metastasizing middle ear carcinoid previously reported.

OBJECTIVE

To present a case of metastasizing middle ear carcinoid, to review previously reported cases, and to discuss the clinical nature of this tumor, which is similar to "orthotopic" carcinoids bearing definite metastatic potential.

STUDY DESIGN

Case report. PATIENT, INTERVENTION, RESULTS: We present a 72-year-old woman who developed ipsilateral parotid gland and cervical lymph node metastases 8 and 11 months after surgical removal of a primary middle ear lesion. She subsequently required 2 revision procedures and radiotherapy for local recurrences. Her case was complicated by nonsurgically induced permanent facial nerve paralysis, the cause of which remains obscure. At the end of the 8-year follow-up, the patient was alive with locally, recurrent tumor eroding the cranial base and invading the posterior intracranial fossa but with no signs of metastases.

MAIN OUTCOME MEASURES

Light microscopy and immunohistochemical analysis.

CONCLUSION

Considering the reported high rate of recurrence and their consequent metastases, a middle ear carcinoid should be classified as a neuroendocrine low-grade carcinoma.

[Mixed endocrine tumors]

Mixed endocrine tumors are tumors composed of at least two distinct tumor populations, one of which is endocrine. Because of their rarity and unusual presentation, endocrine mixed tumors raise many problems of diagnosis, management and therapy. Three main types of endocrine mixed tumors are recognized: The existence of these various types has been confirmed by recent molecular studies, even if the same studies have also shown that the histogenesis of a mixed endocrine tumor cannot be predicted from its histological features. Composite tumors are the less rare mixed tumors. The recent WHO classification recommends to restrict the term of composite endocrine tumor to the epithelial tumors containing at least 30% of obviously tumoral endocrine cells; some authors recommend to use higher thresholds, of at least 50%, in order to avoid overdiagnosis. The endocrine component is usually well differentiated, easily identified by its suggestive histological features; the endocrine nature of tumor cells is confirmed by the immunodetection of specific endocrine and neuro-endocrine markers (such as chromogranin A and synaptophysin). In some cases, the endocrine component is poorly differentiated: the demonstration of neuro-endocrine markers is necessary to confirm the diagnosis. Mixed tumors can occur in every anatomical site; they are more frequent in organs containing endocrine cells in the normal state (especially the digestive tract and the pancreas), but they can also be observed in organs devoid of endocrine cells (such as the mammary gland). The management of mixed endocrine tumors must take into account the more aggressive component. Mixed tumors containing a well differentiated endocrine component and an adenocarcinomatous component are to be treated like adenocarcinomas. Mixed tumors containing a poorly differentiated endocrine component must be considered as poorly differentiated endocrine carcinomas.

Aspiration cytopathology of middle-ear neuroendocrine carcinoma

Primary neuroendocrine carcinoma (carcinoid tumor) is among the rarest of middle-ear (ME) neoplasms, with only a rare case of metastatic disease having been reported. Fine-needle aspiration biopsy (FNAB) was performed in a 51-yr-old male with a two-decade history of multiple local recurrences from a right middle-ear neoplasm, with the most recent surgical excision 2 yr ago. He currently presented with an enlarged right parotid gland, and a right infratemporal mass. Aspirate smears showed a monotonous population of cytologically bland cells with a small to moderate amount of pale granular cytoplasm, round to oval nuclei, inconspicuous nucleoli, and finely granular chromatin. Rare, isolated large cells were occasionally seen. Immunohistochemical staining of the cell block made from the aspirated material showed strong cytoplasmic positivity for chromogranin, synaptophysin, neuron-specific enolase (NSE), serotonin, and cytokeratin cocktail, and negative staining for S100 protein. Review of tissue slides from the patient's prior middle-ear tumor showed an identical immunoprofile and morphology, and led to a revision of the original diagnosis of paraganglioma. Middle-ear neuroendocrine carcinoma has a low but definite metastatic potential, which can be diagnosed using FNAB if ancillary immunohistochemical studies are available.

Middle ear adenocarcinoma with intracranial extension. Case report

Middle ear adenocarcinoma is a very rare, locally invasive neoplasm assumed to arise from the middle ear mucosa. Although endolymphatic sac tumor (aggressive papillary middle ear tumor) and jugulotympanic paraganglioma may show brain invasion, intracranial extension of histologically confirmed middle ear adenocarcinoma has not been previously reported. The authors describe a 53-year-old man who suffered from otalgia and tinnitus for more than 10 years and from neurological deficits for 1 year due to a large temporal bone tumor that invaded the temporal lobe. A combined neurosurgical and otolaryngological resection was performed. Pathological analysis revealed a low-grade adenocarcinoma of a mixed epithelial-neuroendocrine phenotype, which showed a close histological similarity to, and topographical relationship with, middle ear epithelium. The authors conclude that middle ear adenocarcinoma belongs to the spectrum of extracranial tumors that have possible local extension to the brain.

Middle ear carcinoid: an indolent tumor with metastatic potential

BACKGROUND

Neuroendocrine tumors of the head and neck region may present problems in diagnosis. Middle ear carcinoid is a rare, recently recognized tumor, which to date has not been reported to metastasize.

METHODS

We report the case of a 64-year-old man with a 9-year history of recurrent middle ear neoplasm and ipsilateral cervical lymphadenopathy. A microscopic parathyroid tumor was also identified. The approach to the diagnosis of this unusual combination is presented.

RESULTS

The patient had a neuroendocrine tumor metastatic to multiple unilateral cervical lymph nodes, which was morphologically identical to his recurrent middle ear neoplasm. The neoplasm had the morphologic, immunohistochemical, and ultrastructural features of a carcinoid tumor.

CONCLUSIONS

This case illustrates that middle ear carcinoids may metastasize. We suggest that immunohistochemical studies be performed on all biopsy specimens from neoplasms of the middle ear, as distinction from the more common paraganglioma may be difficult on morphologic grounds alone.

Carcinoid tumor of the middle ear in a 28-year-old patient

Carcinoid tumor of the middle ear is an extremely rare condition. The origin of the tumor cells is still speculative and the closeness of relationship to adenomas of the middle ear has been a matter of discussion since the first description of this tumor entity in 1980. In this study we report a case of a 28-year-old male patient with a carcinoid tumor of the middle ear. We present the results of histomorphological, immunohistochemical and electron microscopic examinations and compare our findings to those of previously published cases.

Are papillary adenomas endolymphatic sac tumors?

Papillary adenomas of the temporal bone have been considered as originating from the endolymphatic sac. The radiologic, surgical, and pathologic findings in a patient suffering from von Hippel-Lindau disease with bilateral papillary adenomas of the temporal bone cast some doubt on this site of origin. Radiologically, the center of tumor growth was at the top of the jugular bulb. Intraoperatively, the tumor was found to have reached the lateral wall of the endolymphatic sac, but the lumen was tumor-free. Both ciliated and nonciliated tumor cells were found in the resected tumor, resembling the ultrastructure of normal epithelial lining in the human mastoid. A strong positive immunohistochemical reaction for keratin and negative reactions for vimentin, glial fibrillary acidic protein, and S-100 protein in the tumor tissue of this patient are typical for middle ear mucosa. Therefore, the described papillary adenoma originated from the mucosa of the pneumatic spaces surrounding the jugular bulb, and the theory that the endolymphatic sac is the origin of all papillary-cystic tumors (adenocarcinomas) should be questioned.

Cartinoid tumor of the middle ear and mastoid

Primary cartinoid tumors in the middle ear and mastoid are rare. They are also very difficult to distinguish from adenomas and adenocarcinomas, using conventional histological stains. We present clinical, histological, immunohistochemical and ultrastructural findings of a cartinoid tumor in the middle ear and mastoid in a 40-year-old male. A soft tumor was revealed in the posterior mesotympanum and mastoid cavity, and a radical tympanomastoidectomy was performed. The tumor cells were stained by chromogranin A, and neurosecretory granules were confirmed with electron microscopy. We also review 20 previously reported cases in regard to their presentation, symptoms, signs, tumor extension, treatments, and histopathology.

Carcinoid tumor of the middle ear containing serotonin and multiple peptide hormones. A case report and review of the pathology literature

A 69-year-old man complaining of longstanding hearing loss and mild otorrhea was found to have a mass obliterating the external auditory canal and polypous tympanic mucosa with accompanying absence of the tympanic membrane and ossicular chain. Tumors excised from the external auditory canal and tympanum showed histologic features essentially characteristic of a carcinoid tumor: a ribbon or festoon arrangement of tumor cells, formation of anastomosing cords and glandular spaces, presence of numerous argyrophilic as well as argentaffin secretory granules within many of the tumor cells, and ultrastructural evidence of neurosecretory granules in the tumor cell cytoplasm. Immunohistochemically, the tumor was found to contain not only neuronal marker substances such as neuron-specific enolase, S-100 protein and chromogranin A, but also serotonin and multiple peptide hormones such as pancreatic polypeptide, glucagon, cholecystokinin and leucine-enkephalin. A review of the pathology of 17 previous cases of carcinoid of the middle ear suggested that this type of carcinoid may have a variegated hormone profile among carcinoids of foregut origin, and hormonally may resemble ileal carcinoid arising from the midgut, although their histogenetic origins may differ, because of frequent production of serotonin.

Adeno-carcinoid or amphicrine tumors of the middle ear a new entity?

The clinicopathological, ultrastructural and immunohistochemical characteristics of four primary tumors of the middle ear are reported. These neoplasms showed a striking, heterogeneous aspect ranging from solid-trabecular (Type I) to tubulo-glandular (Type II) growth patterns. Secretory activity of the tumor cells was evaluated by immunohistochemistry and electron microscopy. Based on these procedures, three cell types were found, mainly limited to tumors with a tubulo-glandular (Type II) growth pattern. Most frequent were B-cells with an abundant pale cytoplasm containing neuroendocrine granules, both cytokeratin and vimentin as well as several endocrine marker substances. Less frequent were A-cells, which are slender, darkly staining and line the glandular lumina. They showed exocrine activity only and stained strongly with a polyclonal cytokeratin antibody. Finally, least frequent were amphicrine cells, which were characterized by both lumina and neuroendocrine granules in their cytoplasm and were interpreted as the link between A and B cells. Although this morphological description closely resembles that of carcinoids and adenocarcinoids of the respiratory tract and gut, the clinical behaviour of these middle ear tumors nevertheless seems different, with no recurrence or metastasis after a follow-up of 1 to 14 years (median 78 months). Therefore, some authors suggest that these tumors should be classified as middle ear adenomas or adenomatous tumors. However, we strongly feel that these tumours represent a distinct entity and can be classified as adenocarcinoids or amphicrine tumors, i.e. demonstrating both exocrine and endocrine activities. Further work is required to evaluate the exact proportion of neuroendocrine and amphicrine tumors in the heterogeneous group of adenomas and in the rarely described group of adenocarcinomas.

Middle ear adenoma: tumour of mixed mucinous and neuroendocrine differentiation

Two cases of progressive hearing loss due to middle ear tumours are described. The histological characteristics numbered intraluminal mucin production and neuroendocrine features, as shown by argyrophilia and ultrastructural demonstration of dense core granules. These tumours have been known by many different names, reflecting the controversies relating to their presumed histogenesis and differentiation. The currently preferred designation is middle ear adenoma, and these two cases provide further evidence for dual lines of differentiation.