Editor’s Note: The 11th Sino-French (International) Advanced Breast Cancer Forum (SFBCS) was held in Chongqing on April 19-20, 2024. Experts from around the world shared their knowledge on basic breast cancer research, pathology diagnosis, surgical procedures, and systemic treatment. In the surgical forefront segment, Professor Yongsheng Wang from Shandong Cancer Hospital presented on “Precision Decision-Making in Sentinel Lymph Node Biopsy,” discussing clinical practice decisions and patient benefits related to breast cancer sentinel lymph node biopsy (SLNB). “Oncology Frontier” interviewed Professor Wang at the conference, providing insights into the precise selection of patients for SLNB, diagnosis, and clinical management.
Oncology Frontier : Sentinel lymph node biopsy (SLNB) plays a significant role in reducing patient trauma and improving quality of life. Which patients are suitable for SLNB?
Professor Yongsheng Wang: Since the 1990s, SLNB has accumulated over thirty years of evidence-based medical evidence, and its indications have continually expanded. Currently, all patients with negative axillary lymph nodes (ALN), and those initially ALN cN1 who turn negative after neoadjuvant therapy, are eligible for SLNB to improve quality of life and reduce postoperative complications. SLNB has broad indications; however, there are four main contraindications: first, patients with confirmed ALN positivity through biopsy; second, ALN cN+ patients still positive after neoadjuvant therapy; third, patients with multiple clavicular lymph node transfers ALN cN2-3, even if negative after neoadjuvant therapy, guidelines still require axillary lymph node dissection (ALND); fourth, patients with inflammatory breast cancer.
SLNB, a minimally invasive axillary staging technique, still causes some trauma to patients. Therefore, researchers are exploring non-invasive, non-surgical axillary staging techniques that would exempt patients from SLNB. For example, patients over 70 with positive hormone receptors (HR+), small tumors, and negative ALN might not require axillary staging if their adjunctive therapy decisions are not affected by ALN status, especially if they have significant comorbidities. Ductal carcinoma in situ (DCIS) patients who show no signs of invasive cancer or minimal risk of intraductal cancer invasion during excision biopsy may also be exempted from SLNB. If diagnosed with DCIS via core needle biopsy, SLNB is still necessary. Lastly, patients meeting the SOUND study criteria—tumors ≤2 cm, negative axillary examination and imaging—have shown in studies that SLNB and patients without axillary surgery have comparable five-year distant disease-free survival rates (DDFS) and cumulative incidence of axillary recurrence. However, the clinical application of this study is limited to postmenopausal HR+/HER2- patients, while the auxiliary therapy decisions for HER2 positive or triple-negative breast cancer patients might still be influenced by ALN status, possibly necessitating SLNB.
Oncology Frontier : In the era of precision medicine, how can multi-gene testing technology be used to select optimal patient populations, thus reducing the level of treatment in the axillary region and potentially the entire body?
Professor Yongsheng Wang: Breast cancer has entered the era of precision subtyping, assisted by multi-gene testing technology in addition to conventional pathological subtyping. Multi-gene testing can assess the risk of distant metastasis and, like the 28-gene test, can preliminarily assess the risk of local recurrence, pending further verification by more Phase III clinical trials.
In the future, whether patients with 1-2 positive sentinel lymph nodes can be exempt from postoperative regional lymph node radiation is a significant concern. In clinical practice, when axillary dissection is performed for patients with 1-2 positive SLNs, it is found that more than half of these patients have no residual positive lymph nodes in the axilla, suggesting that regional lymph node radiation for these patients might be overtreatment. Unfortunately, there are currently no effective assessment indicators. In my view, multi-gene testing provides an assessment technology that combines information on tumor burden and tumor biology, which may eventually help identify patients with 1-2 positive SLNs who do not need axillary dissection or postoperative radiation. This is a promising research direction, and I look forward to achieving good research results.
Of course, the more significant application of multi-gene testing is to facilitate de-escalation of systemic treatment. For HR+/HER2- patients with 1-3 positive lymph nodes and those with negative ALN, multi-gene testing can effectively identify patients who can be exempted from chemotherapy. I believe this not only reduces the pain and adverse effects of treatment for patients but also
lowers the overall cost of breast cancer treatment, representing an excellent clinical practice method. Increasingly, more patients suitable for multi-gene testing are utilizing this technology in clinical applications, providing effective guidance for precisely exempting patients from chemotherapy.
Oncology Frontier : For internal mammary lymph nodes (IMLN), how can minimally invasive diagnosis and precise treatment be achieved?
Professor Yongsheng Wang: About 75% of breast cancer lymph fluid drains to the ALN, so there is substantial evidence-based medicine evidence for SLNB regarding the axilla. Clinical practices such as implementing SLNB, exempting ALND, and exploring non-surgical staging methods for the axilla are ongoing. Correspondingly, 25% of breast cancer lymph fluid drains to the IMLN, and the staging and treatment of IMLN transfers are receiving increasing attention.
As early as the 1960s and 1970s, expanded radical mastectomy efforts were made domestically and internationally to clear IMLN for better staging and potentially improve patient prognosis. Unfortunately, due to the lack of effective systemic treatment methods at the time, expanding the scope of surgery did not improve outcomes. In recent years, studies on internal mammary area radiation therapy have been published, showing that administering radiation to high-risk patients for internal mammary transfer not only strengthens regional control and reduces recurrence in the internal mammary area but also significantly improves overall patient survival.
The latest EBCTCG meta-analysis further confirms that adding internal mammary area radiation significantly improves patient survival. The study found that only about one-third of the early-stage clinical study participants at high risk for internal mammary transfer actually had transfers, meaning two-thirds did not benefit from internal mammary radiation. Achieving positive results under the premise of being diluted by two-thirds of the population without IMLN transfers is quite challenging. Thus, clinically, further exploration is needed to effectively screen and exclude patients without IMLN transfers and precisely administer radiation therapy to patients with IMLN transfers, which would further enhance the absolute benefits for this population.
Currently, neither clinical nor pathological indicators can effectively predict IMLN transfers, so we are exploring internal mammary sentinel lymph node biopsy (IM-SLNB). Our multicenter study on new injectable tracer technologies shows that compared to the previous approximate 15% rate of internal mammary imaging, the new injectable tracer technology can increase this rate to about 70%, preliminarily meeting clinical needs. Additionally, another multicenter study using IMLN dissection to verify the accuracy of IM-SLNB found that IM-SLNB had a false-negative rate of only about 3.0%, thus confirming that IM-SLNB, like axillary SLNB, can serve as a minimally invasive staging technique, making lymph transfer staging more precise and providing a good basis for effectively guiding personalized radiation therapy in the future.
Professor Yongsheng Wang
Shandong Cancer Hospital
Second-level Professor, Doctoral Supervisor, People’s Doctor
Director of the Breast Disease Center, Department of General Surgery, Shandong Cancer Hospital
Vice Chairman of the Breast Cancer Professional Committee, Chinese Anti-Cancer Association
Vice Chairman of the International Medical Exchange Branch, Chinese Anti-Cancer Association
Standing Committee Member of the Breast Cancer Expert Committee, Chinese Society of Clinical Oncology
Vice Chair of the Breast Cancer Group, Oncology Branch, Chinese Medical Association
Member of the Breast Cancer Group, Oncology Branch, Chinese Medical Association
Member of the National Health Commission Breast Cancer Diagnosis and Treatment Standards Expert Group
Member of the GBCC International Guidance Expert Committee
