MMP2 and metastatic malignant neoplasm in the lymph nodes: Perturbed MMP2 gene expression was the only molecular biomarker independently associated with poor outcome (hazard ratio 1.38, 95%CI 1.16–1.65, p < 0.001) together with size of the tumor (HR 1.47, 95%CI 1.10–1.96, p < 0.01) and lymph node metastasis (HR 1.71, 95%CI 1.27–2.30, p < 0.001).