p120 is a proliferation-associated nucleolar protein found in most human malignant tumors, but not in resting normal cells. In colorectal cancer the altered localization of p120 Catenin corresponds with loss of cytoplasmic localization of E-cadherin. Studies have shown accurate categorization of ductal vs. lobular neoplasia in the breast was achieved with p120 staining. p120 expression further clarifies the separation of low-grade ductal carcinoma in situ from lobular neoplasia. Studies also have shown that altered expression of p120 Catenin antibody predicts poor outcome in invasive breast cancer.