Survival in patients with submandibular gland carcinoma — Results of a multi-institutional retrospective study

Objective: Clinical studies demonstrating the prognostic factors in submandibular gland carcinoma are limited because the tumor is relatively rare. The aim of this study was to identify clinical outcomes and prognostic factors in submandibular gland carcinoma. Methods: The study included 65 patients with submandibular gland carcinoma who underwent initial surgical treatment at the Kyoto University and its affiliated hospitals. Results: The 3-year overall survival (OS), disease specific survival, locoregional control (LRC), and no distant metastasis (NDM) rates were 74.2%, 74.2%, 90.0%, and 64.8%, respectively. In the current follow-up study, 16 patients died of the disease, 5 patients were alive with recurrence, 43 patients were alive without disease, and 1 patient died of unrelated disease without recurrence. All patients who died of the disease had developed distant metastasis. Based on univariate analysis, tumor grade (high grade) and lymph node metastases (≥N2) were significant prognostic factors for OS and LRC. It also revealed tumor grade (high grade), T classification (≥T3), and lymph node metastases (≥N2) were significant for distant metastasis. Multivariate analysis showed the following significant prognostic factors: lymph node metastases (≥N2) for OS, LRC, and NDM, and high tumor grade for NDM. Conclusion: Our study suggested death of submandibular gland carcinoma occurred mainly due to distant metastasis. The significant predictors of distant metastasis were lymph node metastases (≥N2) and tumor grade (high grade).