Reduced expression of WWOX was also observed in immunohistochemical study of 44 DCIS tumors (68.2%), 31 DCIS tumors adjacent to invasive breast cancer (54.8%), 30 cases of invasive breast cancer (61.3%), 39 normal tissues adjacent to DCIS tumors (56.4%), and 30 healthy tissues surrounding DCIS tumors adjacent to invasive breast cancers (29%). Here, WWOX is linked to ductal breast carcinoma in situ.