Atypical carcinoid (neuroendocrine carcinoma) of the gingiva: Counterpart of a laryngeal tumor

How phenotype guides management of the neuroendocrine carcinomas of the larynx

Objective

This review aimed to critically analyse data pertaining to the clinical presentation and treatment of neuroendocrine carcinomas of the larynx.

Method

A PubMed search was performed using the term ‘neuroendocrine carcinoma’. English-language articles on neuroendocrine carcinoma of the larynx were reviewed in detail.

Results and conclusion

While many historical classifications have been proposed, in contemporary practice these tumours are sub-classified into four subtypes: carcinoid, atypical carcinoid, small cell neuroendocrine carcinoma and large cell neuroendocrine carcinoma. These tumours exhibit a wide range of biological behaviour, ranging from the extremely aggressive nature of small and large cell neuroendocrine carcinomas, which usually have a fatal prognosis, to the less aggressive course of carcinoid tumours. In small and large cell neuroendocrine carcinomas, a combination of irradiation and chemotherapy is indicated, while carcinoid and atypical carcinoid tumour management entails conservation surgery.

Differential Diagnosis in Neuroendocrine Neoplasms of the Larynx

The differential diagnosis of neuroendocrine neoplasms of the larynx is broad and includes lesions of epithelial, mesenchymal, and neuroectodermal origin. These lesions have overlapping clinical and pathologic aspects and must be carefully considered in the differential diagnosis of laryngeal neoplasms. The prognosis and treatment are also different among these tumor types, which necessitates making these distinctions clinically. The current literature was reviewed to provide updated information regarding the epithelial-derived tumors, including carcinoid, atypical carcinoid, small cell neuroendocrine carcinomas, large cell neuroendocrine carcinoma, and squamous cell carcinoma with neuroendocrine component. These tumors are compared and contrasted with non-epithelial-derived tumors such as paraganglioma and nonmucosal tumors, such as medullary thyroid carcinoma. The morphologic and cytologic features are discussed, along with helpful immunohistochemical and ancillary investigations.

A Rare Primary Neuroendocrine Tumor (Typical Carcinoid) of the Sublingual Gland

A typical carcinoid is extremely rare in the oral cavity. We here present a case of a typical carcinoid arising in the sublingual gland of a 62-year-old woman. The tumor was removed by primary excision with 10 mm surgical margins and submandibular dissection. Examination of the tumor showed medium-sized tumor cells that were positive for CD56 and chromogranin A, with no necrosis, and with a mitotic count less than 1/10 HPF. A pathological diagnosis of typical carcinoid was made from both morphological and immunological examinations. One year after excision surgery, there was no tumor recurrence or neck metastasis.

Metastatic Tumours to the Oral Cavity: Report of Three Cases

Background

Metastatic tumours to the oral cavity from distant organs are uncommon and represent approximately 1 - 3% of all oral malignancies. Such metastases can occur to the bone or to the oral soft tissues. Almost any malignancy from any site is capable of metastasis to the oral cavity and a wide variety of tumours have been reported to spread to the mouth.

Methods

Careful examination of the oral cavity and a high degree of clinical suspicion as well as a multidisciplinary approach are suggested.

Results

In this article we present three patients, a female and two males with metastatic tumours to the oral cavity, who were referred to our Department. The primary tumours were invasive lobular breast carcinoma, gastric adenocarcinoma and small cell lung carcinoma respectively.

Conclusions

Metastases to the oral cavity are quite uncommon among population. They usually present with symptoms similar to odontogenic infections and benign tumours, causing a delayed diagnosis and treatment.

Primary neuroendocrine carcinoma in oral cavity: two case reports and review of the literature

Neuroendocrine carcinoma (NEC) is a tumor that occurs in different locations, particularly the lungs and larynx. The oral cavity is a rare site for a primary NEC. This report describes 2 cases of primary NEC in the oral cavity. Case 1 occurred in the anterior mandibular gingiva in a 25-year-old woman and presented with a special histologic appearance. This patient showed no evidence of recurrence 13 months after marginal resection of the anterior mandible. Case 2 was a primary NEC with some foci of squamous cell differentiation arising in the right buccal region in a 38-year-old woman. This patient showed no evidence of disease 8 months after tumor resection and postoperative iodine-125 brachytherapy. To the best of the authors' knowledge, case 1 is the youngest patient with NEC reported in the oral cavity to date in the English-language literature, and case 2 is the first report of a primary NEC in the buccal region.

Moderately differentiated neuroendocrine carcinoma (atypical carcinoid) of the parotid gland: report of three cases with contemporary review of salivary neuroendocrine carcinomas

Primary neuroendocrine carcinomas (NECs) of the salivary glands are rare. Most reported NECs in that region are small cell carcinomas with few cases of large cell undifferentiated carcinoma and typical carcinoid tumors. Only two moderately differentiated NECs (atypical carcinoid tumors) have been previously reported. In the current series, the authors report three additional moderately differentiated NECs (atypical carcinoid tumors) of the parotid gland; two occurred in women and one in a man. All patients were initially treated with parotidectomy, with selective lymph node excision in one, and radiation therapy in another. Follow-up was available for two cases (18 and 79 months). One patient had two local recurrences, developing lymph node and liver metastases requiring further surgery and chemotherapy. Currently, she is alive with disease, on supportive care. The second patient is alive with no signs of recurrence. Patients' work-up excluded the possibility of metastatic NECs to the salivary glands in all cases. Histologically, the tumors demonstrated infiltrating nests, cords and trabeculae of round, oval to spindle shaped cells with moderate to focally abundant eosinophilic cytoplasm, small to prominent nucleoli and chromatin stippling. Scattered rosette-like structures were prominent in one tumor. The highest mitotic counts for the three tumors ranged from 5 to 8 mitotic figures/10 hpfs. Necrosis, focal but distinct, was noted in two tumors, vascular invasion in two tumors and perineural invasion in one tumor. Immunohistochemical staining was diagnostic of neuroendocrine carcinoma, showing uniform positive labeling with broad-spectrum cytokeratin (with a paranuclear punctuate pattern in one case), chromogranin and synaptophysin antibodies. CK20 was negative in two tumors and stained rare cells (<1%) in the third.

Primary typical carcinoid tumour in the retromolar region with prominent squamous differentiation: a case report

Primary carcinoid tumours of the oral cavity are rare, with only one case of atypical carcinoid tumour reported in the literature. In this article, a case of primary typical carcinoid tumour in the retromolar region in a 46-year-old woman is described. Histologically, the tumour was characterized by submucosal proliferation of medium-sized monomorphous epithelioid cells with an organoid and nesting pattern of growth. Mitoses and necrosis were not found. Prominent squamous differentiation was present. Immunohistochemically, the tumour was diffuse positive for cytokeratin (CK) (AE1/AE3), CK7, p63, neurone-specific enolase, synaptophysin, and chromogranin. To the authors' knowledge, this is the first report of primary typical carcinoid tumour in the oral cavity.

A case of primary combined neuroendocrine carcinoma with squamous cell carcinoma in the upper gingiva

Neuroendocrine carcinoma is a rare neoplasm that occurs widely in various organs and tissues. The biological behavior of this tumor in the oral region remains poorly understood. We encountered an extremely rare case of combined neuroendocrine carcinoma with squamous cell carcinoma, occurring at the buccal gingiva in a 62-year-old woman. Left partial maxillectomy was performed. Histological examinations revealed solid nests with extensive necrosis and nuclear palisading at the periphery. The tumor also showed areas of stratified neoplastic squamous differentiation. Immunohistochemically, tumor nests stained positive for synaptophysin, chromogranin, N-CAM (CD56), and neuron-specific enolase. Strong positivity was seen for K14 and K17 in the squamous component and for K7 in the neuroendocrine component. Both components showed K19 staining. Cells with squamous differentiation and K14 staining occasionally expressed p63. The patient showed no evidence of disease as of 23 months postoperatively. Given the aggressive characteristics of neuroendocrine carcinoma, strict follow-up has been performed.

Neuroendocrine cells and associated malignancies of the oral mucosa: a review

Neuroendocrine cells of the oral mucosa constitute an under-recognized component of the diffuse neuroendocrine system with diverse subpopulations and elusive biologic roles in the oral cavity. Primary malignant oral tumors that show a neuroendocrine phenotype display histomorphologic heterogeneity thereby giving rise to a spectrum of lesions in this rare category of oral malignancy. These lesions can be divided into neuroendocrine carcinomas (NECs) of small cell or non-small cell type. The former is further subdivided into the Merkel cell type or the pulmonary type while the latter includes atypical carcinoid tumor and large cell NEC. All histologic subtypes of oral NEC appear to have a strong predilection for men in their fifth or sixth decade and arise predominantly in the non-keratinized oral mucosa. The biologic behavior of oral Merkel cell carcinomas appears to be more aggressive than those of skin. It remains to be determined whether histologic categorization of the remaining tumor subtypes is predictive of patient survival in oral neuroendocrine tumors.