Moderately differentiated or large-cell NEC is a more favored term than atypical carcinoid until more refined classifications for upper respiratory tract NEC are agreed on. Despite the confirmed presence of neuroendocrine cells in the respiratory epithelium of the larynx, the origin of laryngeal NEC remains unknown. p53 mutation might be one of the major molecular steps in the pathogenesis of laryngeal NEC.

Myoepithelioma is a rare but well-characterized group of tumours, among which myoepithelioma of the salivary glands is the best known. We report two patients with myoepithelioma of parotid gland presenting as infra-auricular subcutaneous mass. The lesions were clinically suspected to be epidermal cyst. The biopsies revealed that most of the tumour cells showed epithelioid features with oval or spindle eosinophilic cytoplasm. No ductal or syringomatous epithelial structures were observed. The tumour cells showed cytoplasmic immunoexpressions of vimentin, cytokeratin (AE1/AE3), S-100 protein and smooth muscle actin (SMA). In one patient, a strong calponin positivity was observed. Maguetic resonance imaging (MRI) of both patients revealed exophytic, well-defined, strongly enhancing mass in superficial lobe of parotid gland, confirming the parotid gland origin. Myoepithelioma of parotid gland can be presented as a slowly growing tumour of pre- or infra-auricular area. In dermatologic department, it can be misdiagnosed as various dermal or subcutaneous tumours.

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The pattern of expression of beta1 integrin, which has been known as a stem cell marker of the epidermis, may be helpful in predicting the response to radiation in patients with early glottic carcinoma.