Adjuvant therapy in major salivary gland cancers: Analysis of 8580 patients in the National Cancer Database.

BACKGROUND: Evidence surrounding the effect of adjuvant treatment in salivary gland cancers is limited. The benefit of adding chemotherapy to adjuvant treatment is also of interest. We investigated the association of these treatments with survival and whether this differed by stage or the presence of adverse features. METHODS: A retrospective study of adult salivary gland cancer cases diagnosed from 2004 to 2013 in the National Cancer Data Base (NCDB) was conducted. RESULTS: Treatment with adjuvant radiotherapy was associated with improved survival for both patients with early-stage (hazard ratio [HR] 0.744; P = .004) and late-stage (HR 0.688; P < .001) disease with adverse features. Further addition of chemotherapy to the adjuvant treatment of patients with late-stage disease with adverse features was not associated with a survival benefit (HR 1.028; P = .705). CONCLUSION: Adjuvant radiotherapy is associated with improved survival for patients with adverse features, regardless of stage. The addition of chemotherapy to the adjuvant treatment of patients with late-stage disease with adverse features is not associated with improved outcomes.