WFDC2 and breast cancer: Human epididymis protein 4 (HE4) was found as a marker of cancer recently and has been reported in multiple types of neoplasia [4, 5] such as ovarian cancer [5], endometrial cancer [1], lung cancer [6], and breast cancer [7], whereas there are no reports about HE4 on clinicopathological significance, cellular function, and mechanism in gastric carcinoma.