Trends and clinicopathological predictors of axillary evaluation in ductal carcinoma in situ patients treated with breast-conserving therapy

The aim of this study was to investigate the trends of axillary lymph node evaluation in ductal carcinoma in situ (DCIS) patients treated with breast-conserving therapy (BCT) and to identify the clinicopathological predictors of axillary evaluation. DCIS patients treated with BCT in 2006-2015 at our institute were retrospectively included in the analysis. Patients were categorized into three groups: sentinel lymph node biopsy (SLNB), axillary lymph node dissection (ALND), and non-evaluation. Univariate and multivariate logistic regression analyses were performed to identify factors that predicted axillary evaluation. A total of 315 patients were identified, among whom 135 underwent SLNB, and 15 underwent ALND. The proportion of patients who underwent axillary evaluation increased from 33.0% in 2006-2010 to 53.8% in 2011-2015 (P < 0.001), however, no patients had lymph node metastasis based on final pathology. In multivariate analysis, high-grade tumor favored axillary evaluation (OR = 4.376, 95% CI:1.410-13.586, P = 0.011); while excision biopsy favored no axillary evaluation compared with other biopsy methods (OR = 0.418, 95% CI: 0.192-0.909, P = 0.028). Subgroup analysis of patients treated in 2011-2015 revealed that high-grade tumor (OR = 5.898, 95% CI: 1.626-21.390, P = 0.007) and palpable breast lump (OR = 2.497, 95% CI: 1.037-6.011, P = 0.041) were independent predictors of axillary lymph node evaluation. Despite the significant decrease in ALND and a concerning overuse of SLNB, we identified no axillary lymph node metastasis, which justified omitting axillary evaluation in these patients. High-grade tumor, palpable lump, and biopsy method were independent predictors of axillary evaluations. Excision biopsy of suspicious DCIS lesions may potentially preclude the invasive component of the disease and help to avoid axillary surgery