Impact of extensive intraductal component on recurrence and survival in patients with stage I or II breast cancer treated with breast conservation therapy

Background: The relationship between an extensive intraductal component (EIC) and recurrence and survival in patients with stage I or II breast cancer treated with breast conservation therapy has not been clearly defined. Methods: 133 patients with stage I or II breast cancer who underwent breast conservation therapy between 1978 and 1990 at The University of Texas M. D. Anderson Cancer Center were retrospectively studied. All pathology slides were reviewed to determine tumor size nuclear grade, extent of intraductal component, number of positive lymph nodes, and histologic margins. EIC was defined as ductal carcinoma in situ (DCIS) occupying 25% or more of the area encompassed by the infiltrating tumor and DCIS present in grossly normal adjacent breast tissue. Results: 110 patients are alive, and 23 have died, with a median follow-up of 7 years; 85 of 133 patients had an intraductal component, but only 18 had an EIC. Locoregional control and disease-free and overall survival were not adversely affected by the presence of an EIC Five of 133 patients had a locoregional recurrence, but only one had an EIC. Conclusions: EIC, if negative margins can be achieved, does not adversely affect disease-free or overall survival or local control rates.