Background: For patients with ductal carcinoma in situ (DCIS), multiple national cancer organizations recommend that sentinel lymph node biopsy (SLNB) be offered when treated with mastectomy, but not when treated with breast-conserving surgery (BCS). This study analyzes national surgical trends of SLNB and axillary lymph node dissection (ALND) in DCIS patients undergoing breast surgery with the aim to quantify deviations from national guidelines.
Methods: A retrospective cohort analysis of the American College of Surgeons' National Surgical Quality Improvement Program (ACS NSQIP) database from 2005 to 2017 identified patients with DCIS. Patients were categorized by their primary method of breast surgery, i.e. mastectomy or BCS, then further categorized by their axillary lymph node (ALN) management, i.e. no intervention, SLNB, or ALND. Data analysis was conducted via linear regression and a non-parametric Mann-Kendall test to assess a temporal trend and Sen's slope.
Results: Overall, 43,448 patients with DCIS met the inclusion criteria: 20,504 underwent mastectomy and 22,944 underwent BCS. Analysis of DCIS patients from 2005 to 2017 revealed that ALND decreased and SLNB increased in every subgroup, regardless of surgical treatment modality. Evaluation in the mastectomy group increased overall: mastectomy alone increased from 57.1 to 65.8% (p < 0.01) and mastectomy with immediate reconstruction increased from 58.5 to 72.1% (p < 0.01). Increases also occurred in the total BCS population: partial mastectomy increased from 14.0 to 21.1% and oncoplastic surgery increased from 10.5 to 23.0% (both p < 0.01).
Conclusions: Despite national guideline recommendations for the management of ALN surgery in DCIS patients, approximately 20-30% of cases continue to not follow these guidelines. This warrants further education for surgeons and patients.