Malignant salivary gland tumors of the tongue: A multicenter REFCOR study

Salivary carcinomas of minor salivary glands are very infrequent tumors. When located in the tongue, the therapeutic strategy may comprise upfront surgery, which may be debilitating, and/or (chemo-)radiotherapy. The aim of this study was to identify the prognostic factors of salivary carcinomas of the tongue in a population-based cohort. This retrospective multicentric study, based on the "Reseau d'Expertise Francais sur les Cancers ORL Rares" (REFCOR), included all the patients with a salivary carcinoma of the tongue, diagnosed between January 2009 and December 2018. Dubious slides were reviewed by REFCOR expert pathologists to ensure diagnostic accuracy. Treatment was performed in accordance with national REFCOR recommendations. From 28 centers, 103 patients were included in this study. Median age at diagnosis was 63years, and 60.2% were female. Tumors were adenoid cystic carcinomas (41.7%), mucoepidermoid carcinomas (30.1%), and other adenocarcinomas (28.2%). Primary treatment was surgical for 61.2% of them. Five-year overall survival (OS) and event-free survival (EFS) rates were 84.7% and 38.6%, respectively. In multivariable analysis, EFS was significantly worse in case of nonsurgical treatment, alcohol consumption, and glossotonsillar sulcus involvement. N-positive status was the only significant prognostic factor for OS in multivariable analysis. Salivary carcinomas of the tongue represent a heterogeneous group of rare tumors, with a high risk of recurrence. In this national cohort, surgery was associated with better EFS and N-status was the main independent prognostic factor for OS.