MUC1 and esophageal squamous cell carcinoma: Our previous studies revealed that the expression of CCR7/MUC1 is correlated with regional lymphatic recurrence in pN0 ESCC patients [18, 19]; however, there are few reports of MUC1 expression in ESCC and no available information on the cross-talk between MUC1 and CCR7 in the progression of lymphatic metastasis.