Long-term outcomes and prognosis in submandibular gland malignant tumors: A multicenter study.

OBJECTIVES/HYPOTHESIS: Submandibular gland tumors (SMGTs) are rare and characterized by heterogeneity in histologic profiles. The aim of the present study was to retrieve data on submandibular gland (SMG) malignancies and identify factors influencing survival.

STUDY DESIGN: Retrospective study.

METHODS: A multicenter, retrospective study on patients who underwent primary surgery for SMGTs at three referral centers was performed.

RESULTS: Among 204 patients with SMGTs, 50 (24.5%) with SMG malignancies were analyzed in detail. Definitive pT status was: 21 (42%) pT1, 14 (28%) pT2, 10 (20%) pT3, and five (10%) pT4. Nodal metastases and perineural spread were diagnosed in 15 (30%) and 25 (50%) patients, respectively. High-grade lesions were identified in 32 (64%) patients. Follow-up status, available for 49 (98%) patients, was as follows: 23 (47%) patients were alive without disease, 11 (22.5%) died of disease, five (10.2%) alive with disease, and 10 (20.4%) died of other causes. Five- and 10-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were 66.4% and 57.1%, 76.6% and 72.1%, 69.1% and 62.4%, respectively. At univariate analysis, OS, DSS, and RFS were influenced by pT status, pN status, and perineural spread. OS and RFS were also affected by the presence of facial palsy and pain. RFS was negatively influenced by positive margins. Multivariate analysis confirmed that OS, DSS, and RFS were independently affected by perineural spread, whereas nodal involvement influenced only RFS.

CONCLUSIONS: The malignancy rate of SMGTs is comparable to that reported for parotid tumors. Most patients presented with high-grade lesions. pT status, pN status, and perineural spread significantly affected prognosis.

LEVEL OF EVIDENCE: 4 Laryngoscope, 128:2745-2750, 2018.