Intraoperative Pathology Assessment May Lead to Overtreatment of the Axilla in Clinically Node-Negative Breast Cancer Patients Undergoing Upfront Mastectomy

Examining the false-negative rate of a negative axillary node ultrasound-guided core needle biopsy in breast cancer patients undergoing upfront surgery

BACKGROUND

Axillary assessment in breast cancer is key to determining an upfront surgery or neoadjuvant chemotherapy (NAC) approach. We investigated the false-negative rate (FNR) of axillary-node ultrasound-guided core-needle biopsy (US-CNBx) and the surgical management of pN ​+ ​patients.

METHODS

This single-institution study from 2010 to 2020 included patients with benign findings on US-CNBx and upfront surgery. Statistical analyses were performed via t-tests and chi-squared tests.

RESULTS

95 axillae met inclusion, 23 were pN+, resulting in a US-CNBx FNR of 24.2 ​%. pN ​+ ​patients more frequently had cT2-T3 tumors vs pN0 patients (43.5 ​% vs 27.8 ​%, p ​= ​0.03). Of the 23 ​pN ​+ ​patients, 9 underwent breast-conserving surgery (BCS) and 14 underwent mastectomy. In those with BCS, 7 had 1-2 positive nodes, 2 had ≥3 nodes; 3 received an ALND. In those with mastectomies, 12 had 1-2 positive nodes, 2 had ≥3 positive nodes; 6 received an ALND.

CONCLUSION

In this cohort, US-CNBx had a FNR of 24.2 ​%. pN ​+ ​patients had a greater frequency of cT2-cT3 tumors, therefore clinicians should be cognizant of potential occult nodal disease despite negative CNBx when deciding management.

Does Neoadjuvant Chemotherapy in Clinical T1-T2 N0 Triple-Negative Breast Cancer Increase the Extent of Axillary Surgery?

BACKGROUND

Current management strategies for early-stage triple-negative breast cancer (TNBC) include upfront surgery to determine pathologic stage to guide chemotherapy recommendations, or neoadjuvant chemotherapy (NAC) to de-escalate surgery, elucidate tumor response, and determine the role of adjuvant chemotherapy. However, patients who receive NAC with residual pathological nodal (pN) involvement require axillary lymph node dissection (ALND) as they are Z11/AMAROS ineligible. We aimed to evaluate the impact of NAC compared with upfront surgery on pN status and ALND rates in cT1-2N0 TNBC.

METHODS

The National Cancer Database (NCDB) was queried for women with operable cT1-2N0 TNBC from 2014 to 2019. Demographic, clinicopathologic, and treatment data were collected. Multivariable linear regression analysis was performed to assess the odds of pN+ disease and undergoing ALND.

RESULTS

Overall, 55,624 women were included: 26.9% (n = 14,942) underwent NAC and 73.1% (n = 40,682) underwent upfront surgery. The NAC cohort was younger (mean age 52.9 vs. 61.3 years; p < 0.001) with more cT2 tumors (71.6% vs. 31.0%; p < 0.001), and had lower ALND rates (4.3% vs. 5.5%; p < 0.001). The upfront surgery cohort was more likely to have one to three pathologically positive nodes (12.1% vs. 6.5%; odds ratio [OR] 2.37, 95% confidence interval (CI) 2.17-2.58; p < 0.001) but there was no difference in the likelihood of ALND (OR 1.1, 95% CI 0.99-1.24; p = 0.08).

CONCLUSION

Patients who underwent upfront surgery were more likely to be pN+; however, ALND rates were similar between the two cohorts. Thus, the use of NAC does not result in a higher odds of ALND and the decision for NAC should be individualized and based on modern guidelines and systemic therapy benefits.