Utilization of lymph node assessment in patients with ductal carcinoma in situ treated with lumpectomy

Background: Lymph node assessment (LNA), including sentinel lymph node biopsy (SLNB), is controversial in patients undergoing lumpectomy for ductal carcinoma in situ (DCIS). Our goal was to identify factors influencing LNA in these patients. Methods: We used the Surveillance Epidemiology and End Results database to identify all female patients treated with lumpectomy for DCIS from 2000 to 2008. We excluded patients without histologic confirmation, including those diagnosed at autopsy, and those for whom LNA status was unknown. Multivariate logistic regression models predicted use of LNA. Likelihood of undergoing LNA was reported as odds ratios (ORs) with 95% confidence intervals (CIs). Results: A total of 62,935 patients met inclusion criteria. Approximately 15% (N = 9726) had regional LNA at the time of lumpectomy, with 12% (N = 7294) undergoing SLNB. Factors associated with an increased likelihood of undergoing LNA included treatment in the Southeast (OR 1.25, CI 1.04-1.22); treatment after the year 2000; grade II (OR 2.71, CI 2.48-2.96), III (OR 2.38, CI 2.18-2.59), or IV (OR 2.61, CI 2.37-2.88) tumors; DCIS size 2-5 cm (OR 1.49, CI 1.37-1.62) or >5 cm (OR 2.16, CI 1.78-2.61), and estrogen receptor-negative (OR 1.29, CI 1.16-1.43) or progesterone receptor-negative (OR 1.22, CI 1.11-1.33) tumors. Factors associated with a decreased likelihood of undergoing regional LNA were age >60 (OR 0.83, CI 0.79-0.87), and Asian race (OR 0.88, CI 0.81-0.96). Factors predictive of LNA in general were also predictive of SLNB. Conclusions: Although LNA is controversial for patients undergoing lumpectomy for DCIS, it is used in 15% of cases. Further research establishing for the benefit of LNA in DCIS patients treated with lumpectomy is needed.