DCIS and axillary nodal evaluation: Compliance with national guidelines

Background: The National Comprehensive Cancer Network (NCCN) and the American Society of Clinical Oncology (ASCO) provide guidelines regarding axillary nodal evaluation in ductal carcinoma in situ (DCIS), but data regarding national compliance with these guidelines remains incomplete. Methods: We conducted a retrospective review of the National Cancer Data Base (NCDB) analyzing all surgical approaches to axillary evaluation in patients with DCIS. Logistic regression analysis was used to assess the multivariate relationship between patient demographics, clinical characteristics, and probability of axillary evaluation. Results: We identified 88,083 patients diagnosed with DCIS between 1998 and 2011; 31,912 (37%) underwent total mastectomy (TM) and 55,349 (63%) had breast conserving therapy (BCT). Axillary evaluation increased from 44.4% in 1998 to 63.3% in 2011. In TM patients, axillary evaluation increased from 74.3% in 1998 to 93.4% in 2011. This correlated with an increase in sentinel lymph node biopsy (SLNB) from 24.3 to 77.1%, while ALND decreased from 50.0 to 16.3% (p <0.01). In BCT patients, evaluation increased from 20.1 to 43.9%; SLNB increased from 7.2 to 39.4% and ALND decreased from 12.9 to 4.5%. Factors associated with axillary nodal evaluation in BCT patients included practice type and facility location. Among TM patients, use of axillary lymph node dissection (ALND) for axillary staging was associated with earlier year of diagnosis, black race, and older age, as well as community practice setting and practice location in the Southern US. Conclusions: Compliance with national guidelines regarding axillary evaluation in DCIS remains varied. Practice type and location-based differences suggest opportunities for education regarding the appropriate use of axillary nodal evaluation in patients with DCIS.