Prognostic values of pathologic findings and hypoxia markers in 21 patients with salivary duct carcinoma.

BACKGROUND

Salivary duct carcinoma (SDC) is associated with aggressive clinical behavior.

METHODS

We examined the prognostic values of clinicopathologic variables and hypoxia biomarker expression in 21 patients with SDC treated by resection with/without neck dissection and radiotherapy. Tissue microarrays constructed from tumor blocks were stained with monoclonal antibodies to hypoxia-inducible factor (HIF)-1alpha, HIF-2alpha, carbonic anhydrase-9, glucose transporter-1, and erythropoietin receptor. Locoregional control and survival rates were calculated by the Kaplan-Meier method and prognostic factors were calculated from uni- and multivariate analyses.

RESULTS

The cervical nodal metastasis rate was 67% at initial diagnosis and the distant metastasis rate was 71% during follow-up. The only significant predictor of distant metastasis was nodal metastasis (P = 0.006). Actuarial 5-year locoregional control, distant metastasis-free survival, and overall survival rates were 57%, 40%, and 44%. Multivariate analysis showed that lymphovascular and perineural invasion and radiotherapy were independent predictors of overall survival (P < 0.025). None of the hypoxia biomarkers, however, was a significant predictor of locoregional control, distant metastasis, or survival.

CONCLUSIONS

Lymphovascular and perineural invasion, but not hypoxia biomarkers, were significant prognostic factors for patients with SDC.