Axillary Management for Patients With In-Situ and Invasive Breast Cancer

Publication Date: March 13, 2022
Last Updated: May 2, 2022

Recommendations

Indications for no surgical axillary lymph node staging

  1. When surgical nodal staging will not affect adjuvant therapy recommendations.
    • Axillary staging is of little value in the setting of advanced age, serious comorbidities, or when it will not affect decisions regarding adjuvant therapy.
  2. Pure DCIS undergoing breast-conserving surgery.
    • Patients with DCIS and no clinical or radiologic suspicion of invasion do not require axillary staging. The overall risk of nodal metastasis for DCIS is approximately 1-2%.
  3. ≥70 years of age with cT1-2N0 hormone receptor positive breast cancer
    • 62% of patients in the CALGB 9343 RCT did not have axillary staging. Survival was unaffected, and only 3% developed axillary recurrence. This trial is the basis of the current SSO Choosing Wisely guideline recommendation against routine SLNB in patients age 70+ with HR+/HER2- invasive breast cancer.
  4. Prophylactic mastectomy
    • Axillary staging is not recommended for prophylactic mastectomy, as the likelihood of incidentally finding invasive cancer is about 2% and about 1% for nodal metastases.
  5. Primary breast sarcoma or phyllodes tumor
    • The risk of nodal metastasis for breast sarcoma - including angiosarcoma and malignant phyllodes tumor - is negligible.

Indications for sentinel lymph node biopsy (SLNB)

  1. cT1mi-3N0 (palpably node-negative) cancer
    • SLNB is indicated for most patients with cN0 breast cancer. This is supported by an extensive body of literature, but with variable use of axillary imaging, so is indicated even if a previously non-palpable, image-detected node was found to contain metastasis.
  2. cT1-2N0 (palpably node-negative) cancer with abnormal axillary imaging and/or a positive lymph node needle biopsy
    • About 70% of patients with a normal axilla on physical examination but abnormalaxillary imaging - and about 50% of those with a positive FNA/core needle biopsy – will have 1-2 SLN+ and have the option to avoid ALND.
  3. DCIS with a mass, other suspicion of invasion, or requiring mastectomy
    • SLNB is appropriate for DCIS whenever the risk of upstaging to invasive cancer is increased. SLNB is feasible post-mastectomy, but its performance in this setting is unproven.
  4. cT1-2N0 (palpably node-negative) cancer with 1-2 SLN+ having BCT with WBRT
    • SLNB without ALND is appropriate for patients undergoing BCT who meet the entry criteria of the IBCSG 23-01 and Z0011 trials and are found to have 1 or 2 positive SLN.
  5. cT1-2N0 (palpably node-negative) cancer having mastectomy, with 1-3 SLN+ and receiving axillary RT
    • SLNB without ALND is appropriate for patients undergoing mastectomy with 1-3 positive SLN who meet the entry criteria for the AMAROS and OTOASOR trials. The data for 3 SLN+ may be insufficient, in that 95% of AMAROS patients had 1-2 SLN+
  6. cN0 (palpably node-negative) cancer post neoadjuvant therapy
    • Upfront image-guided needle biopsy is indicated for any patient with clinical or radiologic suspicion of node metastasis - SLNB should not be done prior to neoadjuvant therapy. SLNB performs well in the post-neoadjuvant setting, and axillary US can suggest treatment response but is not reliable enough to determine the surgical approach. SLNB is suitable for patients who were palpably nodenegative, or biopsy-proven node-positive upfront, as long as they are palpably node-negative post-neoadjuvant. For patients who were biopsy-proven nodepositive upfront, the false-negative rate of SLNB is minimized by the retrieval of >2 SLN, by dual mapping, and by retrieval of the biopsied/clipped node. The data for patients presenting with cN2 disease may be insufficient – in ACOSOG Z1071 (below) 95% of patients had cN1 disease on presentation.
  7. Invasive local recurrence post-BCT with a cN0 axilla
    • SLNB is feasible for patients with prior BCT/SLNB or BCT/ALND who present with invasive local recurrence and a cN0 axilla. All patients with invasive local recurrence require systemic adjuvant therapy, so it is not yet clear if the results of a reoperative SLNB are meaningful in this setting

Indications for axillary dissection (ALND)

  1. cN2-3 on presentation (palpably node-positive and biopsy-proven)
    • To avoid false-positives, needle biopsy is indicated to confirm node status in all patients with clinical or radiologic suspicion of node metastasis. Most patients with cN2-3 disease will receive neoadjuvant therapy, and since the performance of SLNB in this setting is uncertain, ALND is appropriate either upfront (for patients who are ineligible for neoadjuvant) or post-neoadjuvant.
    • Supraclavicular and/or internal mammary nodal disease is best treated with systemic therapy and RT.
  2. cN0 with positive SLN and ineligible for IBCSG 23-01/Z0011/AMAROS/OTOASOR
    • In the setting of upfront surgery, ALND is appropriate for BCT patients with >2 SLN+ and for mastectomy patients with >3 SLN+.
  3. cN1-2 (palpably node-positive and biopsy-proven) and ineligible for neoadjuvant therapy
    • ALND is appropriate for patients with cN1-2 disease who are not candidates for neoadjuvant therapy.
  4. cN1-2 (palpably node-positive) post-neoadjuvant therapy
    • ALND is indicated for patients who remain palpably node-positive following neoadjuvant therapy.
  5. cN0 and SLN+ post neoadjuvant therapy
    • For upfront surgery, the oncologic outcomes of axillary RT vs ALND for patients with cN0 disease are comparable, with less morbidity for axillary RT. This has not yet been demonstrated for the post-neoadjuvant setting, and ALND is indicated for patients who are cN0 but SLN+. The Alliance A 011202 trial (a randomization of patients with positive SLN post-neoadjuvant to ALND vs axillary RT) is evaluating axillary RT as an alternative to ALND for future patients.
  6. Inflammatory breast cancer
    • Limited data on the performance of SLNB post-neoadjuvant for inflammatory breast cancer indicate low success and high false-negative rates. ALND is indicated in this setting.
  7. Invasive local recurrence with a cN1-2 (palpably node-positive and biopsy-proven) axilla
    • ALND is indicated for patients with invasive local recurrence and clinically positive nodes.
  8. Axillary metastasis from occult breast primary
    • Most patients with axillary metastasis from an unknown breast primary are candidates for neoadjuvant therapy, but ALND is appropriate for those who are ineligible or remain node-positive post-neoadjuvant.

Sequencing treatment to minimize the odds of ALND

Tumor subtype is an important predictor of lymph node response to neoadjuvant chemotherapy, with rates of nodal pathologic complete response (pCR) ranging from about 20% for ER+/PR+/HER2- to over 90% for ER-/PR-/HER2+. Most patients with palpably nodepositive axillae will be referred for neoadjuvant therapy - regardless of tumor subtype - to downstage the breast/axilla. For patients who are palpably node-negative, the rates of ALND for the unresponsive subtype ER+/PR+/HER2- (most of whom will remain node-positive post-neoadjuvant) will be minimized by a strategy of upfront surgery, in that most will have 0-2 SLN+ and can avoid ALND. For those with the responsive subtypes ER-/PR-/HER2- and ER-/PR-/HER2+, the rates of ALND will be minimized by a strategy of neoadjuvant chemotherapy

Prevention of lymphedema

Lymphedema is a significant complication of ALND, affecting approximately 20% of patients. The only clear risk factors are BMI and extent of axillary surgery, but chemotherapy and especially RT are additive. The benefit of standard therapies is uncertain. Newer surgical techniques, such as axillary reverse mapping, lymphatic transfer, and lympho-venous anastomosis are promising both for prevention and for treatment of established lymphedema. However, well-designed prospective studies with uniform criteria for patient selection, procedure, and outcome assessment are needed. In institutions where these techniques are available, they should be considered whenever ALND is required.

Recommendation Grading

Overview

Title

Axillary Management for Patients With In-Situ and Invasive Breast Cancer

Authoring Organization

American Society of Breast Surgeons

Publication Month/Year

March 13, 2022

Last Updated Month/Year

April 1, 2024

Document Type

Consensus

Country of Publication

US

Document Objectives

To outline axillary management of patients with in situ and invasive breast cancer.

Inclusion Criteria

Female, Adult, Older adult

Health Care Settings

Hospital, Operating and recovery room

Intended Users

Nurse, nurse practitioner, physician, physician assistant

Scope

Management

Diseases/Conditions (MeSH)

D001943 - Breast Neoplasms, D000071960 - Breast Carcinoma In Situ, D001365 - Axilla

Keywords

breast cancer, breast axilla