Ductal carcinoma in situ of the breast - Long term results from a twenty-year cohort

Abstract

Introduction Long-term survival is excellent in ductal Carcinoma in situ (DCIS); whether or not we are over-treating DCIS has been a major public concern. This study aims at reviewing the long-term survival outcome of DCIS and identifying adverse prognosticators for DCIS. Patients and methods Patients treated for DCIS between 1st January 1997 and 31st December 2016 were identified from a prospectively maintained database. Multivariate analysis was performed to evaluate the adverse factors for surgical margin involvement and local recurrence Results 3042 female patients were treated for breast cancer over the 20-year study period, of which 203 (6.7%) had DCIS in final pathology. The median age of diagnosis was 53 year-old (Range 30–85). 57 (28.1%) were detected by screening mammogram, 101 had breast mass on presentation. 132 (65%) patients received mastectomy and the remaining received breast conserving surgery (BCS); Sentinel lymph node biopsy was performed in 86 (42.4%) patients. 19 (9.4%) patients had positive resection margin, 18 were re-operated for clear resection margin. Multivariate analysis found that high grade DCIS is the only independent risk factors for margin involvement (HR 2.55, 95% CI 1.02–6.42). After median follow-up of 106 months (6–223 months), the overall survival was 97%. 4 (2%) patients developed local recurrence. Multivariate analysis found that positive surgical margin is the only independent factor of local recurrence (HR 9.58, 95% CI 1.43–64.18). Conclusion High grade DCIS is associated with increased risk of surgical margin involvement which is in turn an independent factor of local recurrence.