Predictors of recurrence and survival after salivary gland cancer surgery: A multicenter, retrospective study in northern Japan

Abstract

Objectives: Salivary gland cancer is a rare disease composed of more than 20 histological types with different grades of malignancy. The aim of this multicenter, retrospective study was to identify the most important predictors affecting recurrence and survival after surgery.

Material and methods: A total of 543 patients with salivary gland cancers that underwent curative surgery between 2012 and 2022 in 13 institutions in northern Japan were evaluated in this study. Predictors affecting recurrence and survival were identified by univariate and multivariate Cox regression analyses. Age, sex, primary site, histological type, pathological T status, surgical margin, lymph node metastasis, extranodal extension, and postoperative radiotherapy were the variables evaluated.

Results: Multivariate Cox regression analysis showed that increasing age, submandibular cancer, pathological T status 3 or 4, positive surgical margin, and lymph node metastasis, especially with extranodal extension, were independent risk factors for both recurrence and survival. Sublingual cancer was an independent risk factor for recurrence. Postoperative radiotherapy was associated with a lower risk of recurrence and a good prognosis, and adenoid cystic carcinoma was associated with a good prognosis.

Conclusion: Lymph node metastasis with extranodal extension was the most important prognostic factor affecting both recurrence and survival after surgery, adenoid cystic carcinoma was associated with a good prognosis, and postoperative radiotherapy was associated with a lower risk of recurrence and a good prognosis.

Keywords: Adenoid cystic carcinoma; Disease-free survival; Head and neck cancer; Salivary gland cancer; Survival analysis.