A low risk of recurrence after breast-conserving surgery for DCIS: A single-institution experience.

Background: Previously published studies report up to 30% recurrence rates after DCIS, so it would be desirable to identify those women at risk for recurrence and adapt adjuvant management. This study aimed to identify the locoregional recurrence rate after breast conserving surgery (BCS) for DCIS, and to evaluate the possible role of immunohistochemical (IHC) staining in predicting the risk of recurrence.

Patients And Methods: In a retrospective cohort study, patients who underwent BCS for pure DCIS were identified. Data on well-established clinical-pathological risk factors and development of locoregional recurrence was gathered from patient files. In addition, IHC stains of ER, PR, HER2, p53, and ki67 were performed on original tumor samples. Univariable Cox regression analyses were performed to identify possible risk factors for locoregional recurrence.

Results: 190 patients were included. At a median follow-up time of 12.8 years fifteen (8%) patients developed locoregional recurrence: 7 invasive cancer and 8 DCIS. These recurrences were diagnosed within a range of 1.7 to 19.6 years after the initial diagnosis. Univariable Cox regression analysis did only show a significant association between p53 and locoregional recurrence. Our re-excision rate to obtain free margins was 30.5%, and 90% received radiotherapy. Endocrine treatment was not used.

Conclusions: At 12.8 years follow-up, patients with DCIS treated with BCS have a very low locoregional recurrence of 8%. Although we could demonstrate that increased p53 expression is a risk factor for locoregional recurrence, we think this is of little clinical value in our population with such a low recurrence rate.

Microabstract: With a published recurrence rate up to 30% after DCIS, it would be desirable to identify those at risk to adapt treatment and follow-up. We aimed to evaluate the role of immunohistochemical staining to determine the risk of locoregional recurrence, in addition to established clinical and pathological risk factors. At a median follow-up of 12.8 years, we found a locoregional recurrence rate of 8%. Increased expression of p53 is associated with an increased risk of locoregional recurrence.