KiSl—A novel monoclonal antibody which recognizes proliferating cells: Evaluation of its relationship to prognosis in mammary carcinoma

Abstract

Immunohistochemical staining with a novel monoclonal antibody, KiSl, which recognizes a cell cycle‐associated antigen, was investigated in 142 cases of stage I and II invasive breast carcinoma. KiS 1 staining indices were compared with disease‐free interval, overall survival, and post‐relapse survival. Using a semi‐quantitative method of assessment, we found that tumours with a high level of staining (34/142,24 per cent) had a significantly worse prognosis than those with a low level of staining (108/142, 76 per cent). Significant correlations were found between KiS1 staining and disease‐free interval (PPP=0·01). We conclude that KiS1 is a valuable new antibody which affords useful prognostic information in breast carcinoma. As it can be used in formalin‐fixed, paraffinembedded material, it may be of particular use in the study of small lesions such as those identified in the Breast Cancer Screening Programme.