Management of Clinical N1 Disease After Neoadjuvant Chemotherapy in Patients with Breast Cancer

Following neoadjuvant chemotherapy for breast cancer:

• Pathologic complete response (pCR) in the axillary nodes:
  • Is found in 40% of patients presenting with biopsy proven node-positive disease.
    • This observation led to several clinical trials including:
      • American College of Surgeons Oncology Group (ACOSOG Z1071)
      • SENTINA (Arm C)
      • SN FNAC
        • This trials evaluated the feasibility and accuracy of sentinel lymph node mapping (SLNM) and sentinel lymph node biopsy (SLNB) dissection as axillary staging after neoadjuvant chemotherapy in clinical N1 disease.
        • Although the false-negative rate of SLNB in this setting was above the predetermined threshold, several important factors associated with and impacting the false negative rate were described.
          • This included:
            • Use of dual agent mapping technique
            • Evaluation of at least 3 SLNs
            • Immunohistochemistry (IHC) evaluation in addition to H&E staining
            • Excision of the clipped (biopsy proven) node.

• The ACOSOG Z1071 trial evaluated the false-negative rate (FNR) in patients with clinical N1 disease in whom at least 2 SLNs were identified:
  • This FNR was 12.6%.
  • The FNR was improved to 10.8%:
    • In patients in whom both radioisotope and blue dye were used.
  • In addition, the FNR in the Z1071 trial varied based on the number of SLNs identified:
    • For patients with a single SLN identified,:
      • The FNR was 31.5%
    • For those with 2 SLNs identified:
      • The FNR was 21.1%
    • For those with 3 or more SLNs identified:
      • The FNR was 9.1%

• Data from the SENTINA trial also showed an improved FNR in patients in whom 3 or more SLNs were identified:
  • The trial was a 4-arm multicenter study.
  • Arm C was similar to the ACOSOG Z1071 trial in that it included patients who were clinically node-positive and converted to clinically node-negative (non-palpable) after chemotherapy:
    • The FNRs were 24.3% when a single SLN was identified
    • 18.5% when 2 SLNs were removed
    • Less than 10% when 3 or more SLNs were removed
  • Similar to the Z1071 trial:
    • The FNR was lower (8.6%) for patients who underwent mapping with radioisotope and blue dye.

• The more recently reported SN FNAC study required the use of immunohistochemistry and considered SLN metastases of any size, including isolated tumor cells, to be positive:
  • Using this definition,:
    • The FNR was 8.4%.
  • If isolated tumor cells identified by immunohistochemistry had been considered negative:
    • The FNR would have increased to 13.3%.

• The results of these findings led to refined technique termed targeted axillary dissection (TAD):
  • This procedure involves SLNB dissection and selective targeted excision of the clipped (biopsy proven) axillary node.
  • Response is documented during chemotherapy with ultrasound and clinical exam.
  • In selected patients planned for TAD, the clipped node is preoperatively localized with an I-125 radioactive seed or wire.
  • Intraoperatively, dual lymphatic mapping for SLN identification is employed and targeted excision of the clipped node is performed.
  • Excision is confirmed with specimen radiograph.
  • In approximately 23% of cases the clipped node will not be a sentinel node.
  • Compared with ALND:
    • The false-negative rate of this approach was:
      • 10.1% with sentinel node biopsy alone
      • 4.2% for excision of the clipped node alone
      • 2.0% for TAD.
  • In carefully selected patients TAD alone may offer an accurate approach to axillary staging and assessment of residual disease with limited morbidity.

Rodrigo Arrangoiz MS, MD, FACS a surgical oncologist and is a member of Sociedad Quirúrgica S.C at the America British Cowdray Medical Center in Mexico City:

• He is an expert in the management of breast cancer.

  • If you have any questions about SLNM and SLNB after neoadjuvant chemotherapy in breast cancer please fill free to contact Dr. Arrangoiz.

Training:

• General surgery:

• Michigan State University:

• 2004 al 2010

• Surgical Oncology / Head and Neck Surgery / Endocrine Surgery:

• Fox Chase Cancer Center (Filadelfia):

• 2010 al 2012

• Masters in Science (Clinical research for health professionals):

• Drexel University (Filadelfia):

• 2010 al 2012

• Surgical Oncology / Head and Neck Surgery / Endocrine Surgery:

• IFHNOS / Memorial Sloan Kettering Cancer Center:

• 2014 al 2016

#Arrangoiz

#Surgeon

#Cirujano

#SurgicalOncologist

#CirujanoOncologo

#BreastSurgeon

#CirujanodeMama

#CancerSurgeon

#CirujanodeCancer

http://www.sociedadquirurigca.com