HETEROGENEITY OF DUCT CARCINOMA IN-SITU (DCIS) - RELATIONSHIP OF GRADE AND SUBTYPE ANALYSIS TO LOCAL RECURRENCE AND RISK OF INVASIVE TRANSFORMATION

Morphologic analysis of nuclear grade and extent of necrosis can provi de reproducible classification of subclinical duct carcinoma in situ ( DCIS) which strongly separates DCIS into three risk groups. For subcli nical lesions of small size, risk is largely limited to local recurren ces only, half of which, however, are invasive events. Local recurrenc es are seen much more frequently with high grade DCIS. Most local recu rrences following breast conservation therapy represent residual disea se in the immediate vicinity of the biopsy site. Stromal and cellular host reactions may provide additional prognostic information.