PurposeTo investigate the distribution of Ki67+ cells in breast cancer in relation to clinical-pathological parameters and prognosis.Materials and MethodsKi67 expression status was detected in 1,086 breast cancer specimens using immunohistochemistry staining and examining the relationship between the Ki67+ cells' location. Subsequently, clinical-pathological parameters and prognosis were determined.ResultsIn total, Ki67 protein expression was found in 781 (71.92%) of the 1,086 breast cancer specimens. Among the 781 Ki67+ cases, 461 were defined as diffuse type and 320 were defined as borderline type. After universal correlation analysis, significant differences were observed in age, histological grade, metastatic nodes, postoperative distant metastasis, and molecular subtype between Ki67+ and Ki67− cases (P = 0.01, 0.001, 0.001, 0.001, and 0.001, respectively). After subgroup analysis, the borderline cases were found to be characterized by a high distant metastasis rate compared to the diffuse cases as well as the Ki67− cases (P = 0.001). No differences were observed between diffuse type or Ki67− cases (P = 0.105). Multivariate analysis showed that age, tumor size, histological grade, lymph node metastasis, molecular subtype, and the Ki67 distribution pattern were observed to be related to postoperative distant metastasis (all P<0.05). Furthermore, borderline type was shown to attain a significantly more distant bone and liver metastasis and worse disease-specific survival than the other types (P = 0.001). In the Cox regression test, the Ki67 distribution pattern was detected as an independent prognostic factor (P = 0.001).ConclusionThe distribution pattern of Ki67 may be a new independent prognostic factor for breast cancer.

In the study, we enrolled 150 breast cancer cases to investigate the expression status of activated leukocyte cell adhesion molecule (ALCAM), and the relationships between ALCAM expression and clinical-pathological characteristics and prognosis of breast cancer. It was observed that ALCAM was expressed at higher levels in breast cancer tissue compared to levels observed for tumor-adjacent tissue. Compared to cancers with low membranous ALCAM expression, cancers with high membranous ALCAM expression were prone to lymph node metastasis (χ2=15.910, P=0.010) and metastasis in general (χ2=5.211, P=0.029). High cytoplasmic ALCAM expression was noticeably correlated with local recurrence (χ2=7.379, P=0.012), especially for short-term recurrence (interval<2 years) (χ2=5.562, P=0.037), while not associated to long-term local recurrence (interval>2 years). The content of ALCAM protein is closely associated with the expression of estrogen receptor (ER) (P=0.024). The disease-free survival of patients with high cytoplasmic ALCAM expression was significantly shorter compared to the cases with low cytoplasmic ALCAM expression (P=0.036). In conclusion, ALCAM expressed at high levels in breast cancer. High membranous expression of ALCAM probably resulted in weakened adherent ability and metastasis. In addition, high cytoplasmic ALCAM expression strengthened invasive ability of malignant cells and then promoted tumor development.