Small Cell Undifferentiated Carcinoma of the Submandibular Gland with Neuroendocrine Features

Abstract

This article reports the clinical, histopathologic, and immunohistochemical findings in a case of small cell undifferentiated carcinoma of the submandibular gland. The tumor was composed of anaplastic cells slightly larger than lymphocytes without ductal differentiation. On immunohistochemical analysis, the tumor contained cells that reacted positively with antibodies to cytokeratin, neuron-specific enolase, synaptophysin, and chromogranin. The present case supports the hypothesis that small cell undifferentiated carcinomas of the salivary glands arise from presumed multipotential ductal stem cells. When this tumor entity is located on the salivary glands, it appears to behave less aggressively than when it is a primary tumor of the bronchial tree.

Proceedings of the NASHNP Companion Meeting, March 18th, 2018, Vancouver, BC, Canada: Salivary Neuroendocrine Carcinoma—An Overview of a Rare Disease with an Emphasis on Determining Tumor Origin

“…Although the reported age range is quite broad (5-91 years), the majority of patients are in the 6th to 8th decade of life with very few patients younger than 40 years of age [2,24]. Men are more commonly affected than women with a male to female ratio of approximately 2-3 to 1 [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. The most common clinical presentation is of a rapidly growing neck mass in the region of the parotid gland or, less commonly, in the submandibular gland (neck level IB).…”

“…Primary neuroendocrine carcinomas (NECs) of the salivary glands are uncommon, accounting for 1-3% or less of major salivary gland malignancies, with existing literature limited to case reports and a few larger case series [1,2]. About three-fourths arise in the parotid with nearly all remaining tumors located in the submandibular gland [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Sublingual and minor salivary gland carcinomas likely exist but are difficult to distinguish from morphologically identical NECs derived from the overlying surface mucosa of the upper aerodigestive tract.…”

“…There is no established grading system for salivary NECs but lung criteria and terminology are generally applied. The overwhelming majority are high-grade with the small cell type out numbering large cell carcinomas by a factor of about 5:1 [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Well and moderately-differentiated NECs are exceedingly rare with < 10 cases described in the literature [19][20][21][22].…”