Disparities in the Surgical Management of the Axilla by Self-Identified Race in the Multicenter Neoadjuvant I-SPY2 Trial.

BACKGROUND

Neoadjuvant chemotherapy (NAC) may allow de-escalation of axillary surgery; yet treatment disparities persist. We aimed to assess race-based disparities in use of axillary lymph node surgery (ALND) among patients who achieve a nodal response in the context of a large, multicenter NAC trial.

METHODS

We conducted a retrospective analysis of the I-SPY 2 trial. All patients received NAC, but type of surgery was not mandated. Multivariable logistic regression was used to predict odds ratio (OR) of undergoing ALND by race while adjusting for clinical and demographic confounders, including age, region, tumor receptor subtype, clinical and pathologic node status (cN and ypN +/-, respectively), and clinical and pathologic tumor size (cT and ypT, respectively).

RESULTS

Among 1394 patients, 79.4% identified as White, 11.2% Black, and 9.4% Asian/other. More than half (52.5%) were cN+ at baseline, and 66.9% were ypN- after NAC, with no significant differences in nodal downstaging by race. Overall ALND rates were higher in Black patients (50.6%) compared to White (37.5%) and Asian/other (38.9%) patients (p = 0.007). Notably, among those who converted from cN+ to ypN-, Black patients underwent ALND more frequently (62%) than White (41.2%) and Asian/other (40%) patients (p = 0.021). In multivariable analysis, Black patients had 70% higher odds of undergoing ALND compared with White patients (OR 1.7, 95% confidence interval (CI) 1.09-2.66, p = 0.02).

CONCLUSIONS

Despite no differences in nodal downstaging, Black patients in I-SPY 2 were significantly more likely to undergo ALND. These disparities may stem from unmeasured patient, provider, or systemic factors affecting surgical planning.