Pathology of preinvasive and excellent prognosis breast cancer.

Our review of recent developments in breast cancer involving the evaluation of patients' tissues is aimed at indicators of increased cancer risk (i.e., the atypical hyperplasias) and lesions without metastatic capacity at time of detection, but those lesions with sufficient risk of attaining metastasis that treatment is mandated (i.e., the ductal carcinomas in situ). We also include invasive lesions with little capacity for metastatic behavior, and highlight the histologic criteria for their recognition, as well as their biologic and clinical characterization. Also discussed are advances in the understanding of diagnostic techniques, particularly core needle biopsy.