Pathology of preinvasive and excellent prognosis breast cancer

We review recent reports on breast cancer and its predictors, emphasizing the clinical utility of tissue samples from patients. We highlight indicators of increased cancer risk and lesions without metastatic capacity at time of detection, but of sufficient risk of attaining metastatic capacity that treatment is mandated ( ie, ductal carcinoma in situ ). Emphasized are histologic features of importance in stratification of ductal carcinoma in situ. We also review invasive lesions with little capacity for metastatic behavior and indicators of low malignant potential. Included are several papers reviewing the usefulness of histologic grading, emphasizing mitotic counts. Also, the continuing utility of recognizing some special and unusual types of breast cancer is detailed. Sentinel lymph node evaluation by histology is included because some minimal or artifactual findings in lymph nodes can mimic true metastases.