Clinicopathological characteristics, treatment and prognosis of oral adenocarcinoma: a population-based study

Objectives: The aim of this study was to identify clinicopathologic features, treatment and prognosis of oral adenocarcinoma (OADC).

Study design: Retrospective cohort analysis.

Setting: National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program.

Methods: Patients diagnosed with OADC between 2000 to 2018 were identified from the SEER database. Overall survival (OS) and disease-specific survival (DSS) were assessed using Kaplan-Meier analyses and Cox regression models.

Results: There were 924 OADC and 37,500 oral squamous cell carcinoma (OSCC) patients identified. Patients with OADC were more significantly associated with younger age, female gender, well differentiation and early AJCC Clinical stage. The study revealed that patients with OADC had better 10-year OS and DSS than those with OSCC (OS: 69.3% vs 40.8%, P < 0.001; DSS: 83.6% vs 53.3%, P < 0.001). The survival advantage still persisted in multivariable analyses (OS: hazard ratio [HR] = 0.427, P < 0.001; DSS: HR = 0.320, P < 0.001). For OADC, multivariable analysis showed that advanced age, stage, and histologic grade were associated with worse OS and DSS, and surgery was associated with better OS and DSS.

Conclusions: OADC has a significantly better prognosis than OSCC, with better differentiation, and more early stage. Surgery was the preferred treatment, for patients with lymph node metastasis, radiotherapy may afford a survival benefit.