RELATIONSHIP BETWEEN GRADE OF INTRADUCTAL COMPONENT OF BREAST-CANCER WITHIN MAIN TUMOR AND EXTENT OF INTRADUCTAL SPREAD IN SURROUNDING TISSUE

Ninety-three specimens obtained by quadrantectomy of invasive ductal c arcinoma of the breast were examined to evaluate the correlation betwe en the grade of the intraductal component within the tumor and the ext ent of intraductal spread in the surrounding tissue. We used immunohis tochemistry of a-smooth muscle actin to visualize the contour of intra ductal components. The grade of the intraductal component within the t umor was classified into 4 groups (td0 to td3) by counting number of i ntraductal components; the extent of intraductal spread in the surroun ding tissue was also divided into 4 groups (sd0 to sd3) according dist ance from the tumor margin. Fifty-eight (89.2%) of 65 cases with low-g rade td were low-grade sd, and 17 (60.7%) cases of high-grade td were high-grade of sd The grade of the intraductal component correlated wit h the extent of intraductal spread in the surrounding tissue, signific antly (p<0.001, Spearman rank correlation test). From these results, w e belive that investigation of intraductal components within the tumor is useful for estimating the extent of intraductal spread in the surr ounding tissue, and excision specimens from diagnostic lumpectomy shou ld be examined for the extent of the intraductal component, the result s being important in estimating the risk of local recurrence.