When correlating MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 expression in tumor tissue in non-invasive and invasive PTC, we report significant positive correlation between TIMP-2 and MMP-2 in the non-invasive tumor group (rho = 0.378, p = 0.039). The gene discussed is MMP9; the disease is neoplasm.