Long-term Follow-up of Pure Ductal Carcinoma in situ after Breast-Conserving Surgery

Yun, Keong Won; Kim, Jisun; Lee, Jong Won; Lee, Sae Byul; Kim, Hee Jeong; Chung, Il Young; Ko, Beom Seok; Son, Byung Ho; Ahn, Sei Hyun

Abstract

PURPOSE
Ductal carcinoma in situ (DCIS) is a high-risk disease for the development of invasive tumors. Although it is associated with excellent prognosis, many patients undergo extensive treatment with surgery, radiation, and endocrine therapy. This study evaluated the clinical and pathologic factors associated with invasive recurrence, particularly locoregional, distant disease after breast-conserving surgery (BCS).
METHODS
This study included 431 patients diagnosed with pure DCIS after BCS between January 2000 and December 2008. The clinicopathological characteristics, margin status, adjuvant therapy, and duration of endocrine therapy were evaluated in hormone receptor-positive DCIS patients.
RESULTS
The median duration of follow-up was 115 months. During this period, 37 cases (8.5%) of recurrence were observed (12 in situ and 23 invasive recurrence and 2 unknown cases). There was no distant metastasis as first event. Similarly, none of the initial in situ recurrence cases developed distant metastasis while eight (32%, 8/23) developed distant metastasis after invasive recurrence. Overall recurrence was associated with young age (â‰¤40 years) (HR: 3.60, 95% confidence interval [CI]: 1.77-7.32) and hormone receptor negativity (HR: 3.33, 95% CI: 1.52-7.29). Invasive local recurrence was independently associated with young age (â‰¤40 years) (HR: 3.86, 95% CI: 1.50-9.96), high nuclear grade (HR: 4.46, 95% CI: 1.62-12.27) and omission of adjuvant radiotherapy (HR: 6.45, 95% CI: 1.82-22.82). Notably, duration of endocrine treatment among the hormone receptor positive patient group, was numerically shorter for recurred patients, though not statistically significant.
CONCLUSION
Young age, high nuclear grade and absence of adjuvant radiotherapy were independently associated with an increased risk of invasive recurrence. Moreover, invasive locoregional recurrence as a first event was associated with worse outcomes, yet in situ recurrence didn't affect overall survival. Further studies with larger sample sizes are warranted to confirm the prognostic indicators of recurrence and the optimal strategy for adjuvant therapy in this setting.