The metastasis rate was 6.5% in low grade MEC patients, no significant difference of total MRP1 expression (P = 0.62) was found between MEC-NM and MEC-M, but a significant difference of nuclear MRP1 expression (P = 0.012) was found between MEC-NM and MEC-M (Table 2). Here, ABCC1 is linked to mucoepidermoid carcinoma.