RESUMEN
BACKGROUND: Internal mammary lymphadenopathy (IML) plays a role in breast cancer stage and prognosis. We aimed to evaluate method of IML detection, how IML impacts response to neoadjuvant chemotherapy (NAC), and oncologic outcomes. METHODS: We evaluated patients enrolled in the I-SPY-2 clinical trial from 2010 to 2022. We captured the radiographic method of IML detection (magnetic resonance imaging [MRI], positron emission tomography/computed tomography [PET/CT], or both) and compared patients with IML with those without. Rates of locoregional recurrence (LRR), distant recurrence (DR) and event-free survival (EFS) were compared by bivariate analysis. RESULTS: Of 2095 patients, 198 (9.5%) had IML reported on pretreatment imaging. The method of IML detection was 154 (77.8%) MRI only, 11 (5.6%) PET/CT only, and 33 (16.7%) both. Factors associated with IML were younger age (p = 0.001), larger tumors (p < 0.001), and higher tumor grade (p = 0.027). Pathologic complete response (pCR) was slightly higher in the IML group (41.4% vs. 34.0%; p = 0.03). There was no difference in breast or axillary surgery (p = 0.41 and p = 0.16), however IML patients were more likely to undergo radiation (68.2% vs. 54.1%; p < 0.001). With a median follow up of 3.72 years (range 0.4-10.2), there was no difference between IM+ versus IM- in LRR (5.6% vs. 3.8%; p = 0.25), DR (9.1% vs. 7.9%; p = 0.58), or EFS (61.6% vs. 57.2%; p = 0.48). This was true for patients with and without pCR. CONCLUSIONS: In this large cohort of patients treated with NAC, outcomes were not negatively impacted by IML. We demonstrated that IML influences treatment selection but is not a poor prognostic indicator when treated with modern NAC and multidisciplinary disease management.
RESUMEN
BACKGROUND: For patients with clinically node-positive (cN+) breast cancer undergoing neoadjuvant chemotherapy (NAC), retrieving previously clipped, biopsy-proven positive lymph nodes during sentinel lymph node biopsy [i.e., targeted axillary dissection (TAD)] may reduce false negative rates. However, the overall utilization and impact of clipping positive nodes remains uncertain. PATIENTS AND METHODS: We retrospectively analyzed cN+ ISPY-2 patients (2011-2022) undergoing axillary surgery after NAC. We evaluated trends in node clipping and associations with type of axillary surgery [sentinel lymph node (SLN) only, SLN and axillary lymph node dissection (ALND), or ALND only] and event-free survival (EFS) in patients that were cN+ on a NAC trial. RESULTS: Among 801 cN+ patients, 161 (20.1%) had pre-NAC clip placement in the positive node. The proportion of patients that were cN+ undergoing clip placement increased from 2.4 to 36.2% between 2011 and 2021. Multivariable logistic regression showed nodal clipping was independently associated with higher odds of SLN-only surgery [odds ratio (OR) 4.3, 95% confidence interval (CI) 2.8-6.8, p < 0.001]. This was also true among patients with residual pathologically node-positive (pN+) disease. Completion ALND rate did not differ based on clip retrieval success. No significant differences in EFS were observed in those with or without clip placement, both with or without successful clip retrieval [hazard ratio (HR) 0.85, 95% CI 0.4-1.7, p = 0.7; HR 1.8, 95% CI 0.5-6.0, p = 0.3, respectively]. CONCLUSION: Clip placement in the positive lymph node before NAC is increasingly common. The significant association between clip placement and omission of axillary dissection, even among patients with pN+ disease, suggests a paradigm shift toward TAD as a definitive surgical management strategy in patients with pN+ disease after NAC.