Small cell carcinoma of the salivary gland: a systematic literature review and two case reports

Salivary gland small cell carcinoma is a rare neoplasm, accounting for less than 1% of salivary gland tumours. Little is known about the epidemiologic factors and treatment of this lesion. The authors report two cases and perform a systematic literature search from 1960 to 2011 for articles on salivary gland small cell carcinoma. Once the papers were reviewed, a database was generated to analyse clinical and pathological features, treatments and outcomes, and an attempt was made to identify prognostic factors. Available data were retrieved for 44 cases which fully satisfied the inclusion criteria; the median age was 64.25 years and the male:female ratio was 2.4:1. The parotid gland was the most common site (79.6%). The overall 1-, 2- and 5-year survival rates were 75.3%, 56.4% and 36.6%, respectively. According to the present review, patient age, tumour size, distant metastasis and cytokeratin-20 positive immunostaining were all significant prognostic factors in a univariate analysis. No particular treatment approach appeared to improve survival. This work reinforces knowledge about salivary gland small cell carcinoma's epidemiologic features, and identifies new prognostic markers. The optimal management of this lesion remains controversial.