Omission of axillary lymph node dissection in patients with ypN+ breast cancer after neoadjuvant chemotherapy: A retrospective multicenter study (KROG 21-06)

BACKGROUND

We evaluated the impact of omitting axillary lymph node dissection (ALND) on oncological outcomes in breast cancer patients with residual nodal disease after neoadjuvant chemotherapy (NAC).

METHODS

The medical records of patients who underwent NAC followed by surgical resection and had residual nodal disease were retrospectively reviewed. In total, 1273 patients from 12 institutions were included; all underwent postoperative radiotherapy. Axillary surgery consisted of ALND in 1103 patients (86.6%) and sentinel lymph node biopsy (SLNBx) alone in 170 (13.4%). Univariate and multivariate analyses of disease-free survival (DFS) and overall survival (OS) were performed before and after propensity score matching (PSM).

RESULTS

The median follow-up was 75.3 months (range, 2.5-182.7). Axillary recurrence rates were 4.8% in the ALND group (n = 53) and 4.7% in the SLNBx group (n = 8). Before PSM, univariate analysis indicated that the 5-year OS rate was inferior in the ALND group compared to the SLNBx group (86.6% vs. 93.3%, respectively; P = 0.002); multivariate analysis did not show a difference between groups (P = 0.325). After PSM, 258 and 136 patients were included in the ALND and SLNBx groups, respectively. There were no significant differences between the ALND and SLNBx groups in DFS (5-year rate, 75.8% vs. 76.9%, respectively; P = 0.406) or OS (5-year rate, 88.7% vs. 93.1%, respectively; P = 0.083).

CONCLUSIONS

SLNBx alone did not compromise oncological outcomes in patients with residual nodal disease after NAC. The omission of ALND might be a possible option for axillary management in patients treated with NAC and postoperative radiotherapy.

Rates of pathologic nodal disease among cN0 and cN1 patients undergoing routine axillary ultrasound and neoadjuvant chemotherapy

PURPOSE

Routine axillary ultrasound (AxUS) in patients receiving neoadjuvant chemotherapy (NAC) remains controversial. Here, we report rates of AxUS-detected nodal disease among patients with normal clinical exams, and rates of pathologic nodal disease after NAC based on method of nodal disease detection.

METHODS

Clinicopathologic findings were prospectively collected for stage I-III breast cancer patients selected for NAC. All patients had pre-treatment AxUS, suspicious nodes were biopsied. The following four patient cohorts were examined: patients with suspicious exam or AxUS but negative biopsy (Suspicious cN0); those with normal exam and normal AxUS (Not Suspicious cN0); those with normal exam but suspicious AxUS and positive biopsy (AxUS-detected cN1); and those with abnormal exam and positive biopsy (exam-detected cN1). Sentinel (SLN) and non-sentinel lymph nodes (non-SLN) were evaluated by immunohistochemistry; nodal metastases of any size were considered positive.

RESULTS

500 patients were included. Of 310 patients with normal axillary exams, 160 had suspicious AxUS, 65 were biopsy-negative (Suspicious cN0) and 95/310 (30.6%) were biopsy-positive (AxUS-detected cN1). Of 190 with abnormal axillary exams, 166 were biopsy-proven node-positive (exam-detected cN1) and 24 were AxUS or biopsy-negative (Suspicious cN0). Rates of pathologic nodal disease were 20/150 (13.3%) among Not Suspicious cN0 patients, 12/89 (13.5%) among Suspicious cN0 (p = 0.97). Rates of residual nodal disease were 55/95 (57.9%) among AxUS-detected cN1 patients, 102/166 (61.4%) among exam-detected cN1 (p = 0.57).

CONCLUSION

AxUS detected nodal disease in 30.6% of patients with normal clinical exams selected for NAC. Rates of pathologic nodal disease were similar among AxUS-detected and exam-detected cN1 patients.

Lymphopenia and clinical outcomes in patients with residual nodal disease after neoadjuvant chemotherapy for breast cancer

BACKGROUND

Patients with residual nodal disease after neoadjuvant chemotherapy for breast cancer have a poor prognosis. We wanted to evaluate whether lymphopenia after treatment for breast cancer impacted clinical outcomes.

MATERIALS AND METHODS

We assessed 99 patients with node-positive disease after neoadjuvant chemotherapy. Absolute lymphocyte count was recorded 1 year after radiation. Dates of local, regional, and distant failure were recorded. Time to event outcomes were evaluated using Kaplan-Meier analysis. Multivariable analysis determined factors predictive for overall survival.

RESULTS

Median follow-up was 44 months (range 3-150). Median age was 48 years (range 23-79). Twenty-six patients (26%) had lymphopenia 1 year after RT. Patients with lymphopenia had a greater incidence of regional (p = 0.03) and distant failure (p = 0.009) compared to those with normal lymphocyte counts and had a 6.05 greater risk of death (p = 0.0002).

CONCLUSIONS

In patients with residual nodal disease after neoadjuvant chemotherapy, lymphopenia after breast cancer treatment was associated with overall survival. The relationship between lymphopenia and breast cancer outcomes warrants further investigation.