Combined imaging, pathology and BRCA1/2 status approach for axilla conserving surgery in node positive breast cancer after neoadjuvant chemotherapy

Background. Pathological complete response (pCR) after neoadjuvant
chemotherapy (NAC) in node positive breast cancer is observed in
considerable proportion of cases. According to NCCN guidelines restaging
of axilla and axilla conserving surgery (ACS) is option if clinical complete
response (cCR) is observed to avoid unnecessary axillary lymph node
dissection (ALND). Marked node biopsy in combination with sentinel node
biopsy have lowest false negative rate. Aim of the study is to evaluate
initial results of ACS in node positive breast cancer after NAC.
Material and methods. From January 2016 e April 2018 60 node positive
stage IIA-IIIC breast cancer cases undergoing NAC were included in the
study. Largest axillary node metastasis confirmed by fine needle aspiration
cytology (FNAC) was marked with V-markTM Breast Biopsy Site Marker
with Titanium Anchor (Argon Medical Devices, Inc), which is not visible in
ultrasound in considerable proportion of cases. Anchor localization in
axilla was confirmed by CT scan. After NAC restaging of axilla was performed with ultrasound and FNAC by responsible surgeon. Modified algorithm of Netherlands cancer institute was followed to decide on ACS
versus ALND as described by Koolen et al, 2017. In case of cN1 and/or ycN0
ACS was performed, including marked node biopsy and sentinel node biopsy. 23% of cases were HER2 positive, 20% triple negative (TN) and 57%
Luminal. 13% cases were BRCA1 positive.
Results. 37 ACS and 23 ALND were performed. In 96.6% of cases titanium
anchor was identified in surgery specimen. In 2 cases anchor was not
identified and its persistence in axilla outside lymph node was confirmed
in postoperative CT scan. In 20/60 (33%) cases pCR in axilla was observed
and in 18/20 (90%) of those cases ACS was performed. 8/20 (40%) cases
were HER2 positive and 8/20 (40%) TN including 6/20 (30%) BRCA1 positive
cases. Only micrometastasis were detected in 9/37 (24%) of ACS cases and
ypN1 stage in another 9/37 (24%) of ACS case.
Conclusion. pCR in axilla is frequent event in node positive breast cancer
after NAC and ALND could be avoided in those cases. Positive node marking
with titanium anchor is technical option for ACS, however necessity to
confirm anchor localization by CT scan is disadvantage of the approach.
Restaging of axilla after NAC with ultrasound and FNAC in combination
with pathological-molecular data like hormone receptors, HER2 and
BRCA1/2 status has potential role to avoid unnecessary ALND.
Conflict of interest: No conflict of interest.