2018-19 Section 7-Neoplastic and Inflammatory Diseases of the Head and Neck eBook

Reprinted by permission of JAMA Otolaryngol Head Neck Surg. 2015; 141(10):905-912.

Research

Original Investigation

Epidemiology, Prognostic Factors, and Treatment of Malignant Submandibular Gland Tumors A Population-Based Cohort Analysis

Robert J. Lee, BS; Andrew P. Tan, MS; Elizabeth L. Tong, BS; Nihal Satyadev; Russell E. Christensen, DDS, MS

Supplemental content at jamaotolaryngology.com CME Quiz at jamanetworkcme.com and CME Questions page 952

IMPORTANCE Malignant tumors of the submandibular gland are uncommon, leading to limited information regarding prognostic factors and difficulty in evaluating treatment modalities.

OBJECTIVE To investigate the correlates of survival in patients with primary malignant tumors of the submandibular gland.

DESIGN, SETTING, AND PARTICIPANTS Data from 2626 patients with a diagnosis of primary tumors of the submandibular gland between 1973 and 2011 in the Surveillance, Epidemiology, and End Results database were used in a retrospective population-based cohort analysis. Kaplan-Meier analysis along with multivariate Cox regression analysis was performed to determine prognostic factors in overall survival (OS) and disease-specific survival (DSS).

INTERVENTIONS Patients were treated with surgery, radiation therapy, both, or neither.

MAIN OUTCOMES AND MEASURES Overall and disease-specific survival.

RESULTS We identified 2626 patients with a diagnosis of primary malignant tumors of the submandibular gland, 52.9%male and 47.1% female, with a mean (range) age of 61.3 (7-101) years. Adenoid cystic carcinoma (36.0%) was the most prevalent histologic subtype, followed by squamous cell carcinoma (18.1%), mucoepidermoid carcinoma (16.9%), and adenocarcinoma (13.7%). Kaplan-Meier analysis demonstrated an OS and DSS of 65% and 74% at 2 years, 54% and 67% at 5 years, and 40% and 60% at 10 years, respectively. Multivariate Cox regression analysis revealed independent predictors of OS and DSS to be age (HR, 1.04 [95% CI, 1.03-1.04], P < .001; HR, 1.02 [95% CI, 1.01-1.03], P < .001), sex (HR, 0.69 [95% CI, 0.57-0.84], P < .001; HR, 0.73 [95% CI, 0.56-0.96], P = .02), tumor grade (HR, 1.47 [95% CI, 1.19-1.81], P < .001; HR, 1.67 [95% CI, 1.25-2.25], P = .001), stage at presentation (HR, 1.56 [95% CI, 1.41-1.72], P < .001; HR, 1.96 [95% CI, 1.69-2.28], P < .001), and surgical resection (HR, 0.55 [95% CI, 0.41-0.74], P < .001; HR, 0.51 [95% CI, 0.35-0.75], P = .001). CONCLUSIONS AND RELEVANCE We report, to our knowledge, the largest study to date focused on correlates of survival in submandibular gland malignant neoplasms. Multivariate analysis found that older age at diagnosis, high tumor grade, and later stage at presentation were correlated with decreased survival whereas female sex and surgical resection were correlated with increased survival. In addition, a 3-cm tumor cutoff size was demonstrated above which was associated with a significantly less favorable prognosis. Radiation therapy had mixed association with survival, dependent on tumor size and subtype.

Author Affiliations: Dental student at School of Dentistry, University of California–Los Angeles (Lee, Tong); medical student at University of Cincinnati College of Medicine, Cincinnati, Ohio (Tan); student at University of California–Los Angeles (Satyadev); Department of Oral and Maxillofacial Pathology, School of Dentistry, University of California–Los Angeles (Christensen). Corresponding Author: Russell E. Christensen, DDS, MS, Department of Oral and Maxillofacial Pathology, University of California–Los Angeles, 10833 Le Conte Ave, CHS 53-058, Los Angeles, CA 90095 ( rchristensen@dentistry.ucla.edu ).

JAMA Otolaryngol Head Neck Surg . 2015;141(10):905-912. doi: 10.1001/jamaoto.2015.1745 Published online September 17, 2015.

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