Optimal treatment of
ductal carcinoma in situ (
DCIS) of the breast requires an improved understanding of its pathologic extent and propensity for local recurrence. This study was performed to analyze mammographic and pathologic features of
DCIS that might predict the extent of disease within the breast and facilitate treatment selection between
lumpectomy alone,
lumpectomy and
radiotherapy, and
mastectomy. At our institution, 60 cases of
DCIS were diagnosed in 59 patients from June 1985 to February 1995 and form the basis of this retrospective study. Demographic and treatment-related information was obtained from hospital and
tumor registry records. Mammograms were reviewed and size estimates of the abnormalities were determined. Pathologic slides from all cases were reviewed and classified according to size group, focality, nuclear grade,
necrosis, and histologic subtype.
DNA ploidy status and proliferation indices were available for 28 patients. Pathologically, 43 (72%) cases were < 15 mm, 14 (23%) were 16 to 40 mm, and 3 (5%) were > 40 mm. Five (8%) of the lesions were multicentric, 28 (47%) focal, and 27 (45%) multifocal. Thirty-three (55%) patients were treated by
mastectomy, 16 (27%) by
lumpectomy alone, and 11 (18%) by
lumpectomy and
radiation therapy. Mammographic size, histologic grade, presence or absence of
necrosis, histologic subtype,
DNA ploidy, and proliferative index were compared with pathologic size and focality by chi 2 analysis. Mammographic size correlated significantly with pathologic size (chi 2 = 11.3; P = 0.02) but underestimated the extent of disease in 9 cases. Although focality correlated significantly with pathologic size (chi 2 = 15.8; P = 0.003), the remaining histopathologic features did not significantly correlate with pathologic size or focality. Histopathologic features, including
DNA studies, do not reliably predict the pathologic extent of
DCIS, but mammographic size and focality do significantly correlate with pathologic size. Nevertheless, most cases of
DCIS are small focal or multifocal lesions that are amenable to breast conservation approaches; further studies are needed to determine the appropriate use of
lumpectomy,
radiation therapy, and
mastectomy in the treatment of
DCIS.