At the 2026 ASCO Annual Meeting, the SENOMAC trial presented its final 5-year overall survival (OS) results together with patient-reported arm morbidity outcomes. The findings further confirmed that, among patients with one or two sentinel lymph nodes containing macrometastases, omission of completion axillary lymph node dissection (ALND) is not only oncologically non-inferior but also significantly improves upper-limb function and lymphedema-related quality of life.Importantly, SENOMAC enrolled a broader population of higher-risk patients—including those undergoing mastectomy, those with T3 tumors, and those with extracapsular extension—thereby extending the evidence supporting axillary de-escalation.
In this edition of ASCO China Perspective, Oncology Frontier invited Professor Jana de Boniface from Capio St. Göran’s Hospital, Stockholm, Sweden, and Professor Yongsheng Wang from Shandong Cancer Hospital to discuss the implications of the five-year SENOMAC results for clinical practice in China, the real-world quality-of-life benefits of omitting ALND, and future directions in axillary de-escalation, including the ongoing SENOMAC-ULTRA trial.
Q1. Oncology Frontier: The SENOMAC trial previously published in the New England Journal of Medicine demonstrated the feasibility of omitting ALND in patients with one or two positive sentinel lymph nodes. This ASCO presentation reports the final overall survival analysis together with patient-reported arm morbidity. Do the longer follow-up data further strengthen the evidence supporting ALND omission?
Professor Jana de Boniface:
Yes. The five-year overall survival data presented at this year’s ASCO meeting further reinforce our conclusion that patients with one or two sentinel lymph node macrometastases can safely omit completion ALND.
The overall survival rates were nearly identical between the two treatment groups. The five-year OS was 93.4% in the ALND group and 94.4% in the group that omitted ALND.
These results clearly demonstrate the non-inferiority of omitting completion axillary lymph node dissection and provide additional high-quality evidence supporting this treatment strategy.
Q2. Oncology Frontier: From the perspective of breast surgery practice in China, what is the clinical significance of the five-year OS and breast cancer-specific survival (BCSS) data reported from SENOMAC for current axillary de-escalation strategies?
Professor Yongsheng Wang:
The five-year overall survival and patient-reported quality-of-life data presented at this meeting are extremely important.
Previously, the five-year recurrence-free survival results from SENOMAC had already influenced clinical practice, expert consensus, and treatment guidelines. Another secondary endpoint—five-year breast cancer-specific survival (BCSS)—was also published in the New England Journal of Medicine in 2024.
This year’s presentation reports the primary endpoint of five-year overall survival, together with another important secondary endpoint evaluating upper-limb morbidity and quality of life. In many ways, this completes the full body of evidence from the trial.
We even joked that if the secondary endpoints had already appeared in NEJM, perhaps the final overall survival results deserved publication in CA: A Cancer Journal for Clinicians. That reflects just how important these data are.
The publication of the complete SENOMAC results will have major implications for axillary surgery in China.
Although multiple studies—including SENOMAC—have demonstrated the oncologic safety of omitting ALND in patients with one or two positive sentinel nodes, implementation remains lower than expected.
According to surveys conducted by the Chinese Anti-Cancer Association Breast Cancer Committee (CACA-CBCS), the proportion of eligible patients actually undergoing ALND omission remains disappointingly low.
For example, the 2025 CACA-CBCS survey found that among patients meeting SENOMAC eligibility criteria:
- 43% of patients undergoing breast-conserving surgery omitted ALND.
- Only 24% of patients undergoing mastectomy omitted ALND.
These figures showed little improvement compared with 2022.
We hope that publication of the five-year survival and quality-of-life data will encourage broader adoption of axillary de-escalation and ultimately improve patients’ quality of life.
The findings are likely to influence practice in several important ways.
1. Expanding eligibility for ALND omission
Compared with previous de-escalation trials, SENOMAC enrolled a substantially broader patient population, including:
- More patients undergoing mastectomy
- A higher proportion of T3 tumors
- More than 30% of patients with extracapsular extension in sentinel lymph nodes
Despite these higher-risk features, excellent oncologic outcomes were maintained.
2. Highlighting the importance of regional nodal irradiation and systemic therapy
Approximately 90% of patients in both treatment groups received regional nodal irradiation.
At present, surgical de-escalation cannot be considered independently of regional radiotherapy, which continues to play an important complementary role.
Likewise, optimal systemic therapy remains essential, as systemic treatment increasingly contributes to local and regional disease control.
3. Improving surgical efficiency
More than 95% of hospitals in China still routinely perform intraoperative assessment of sentinel lymph nodes.
SENOMAC and other trials showed that the median number of retrieved sentinel nodes is only one to two, with more than half of patients having fewer than three nodes identified.
If patients are informed before surgery that ALND can be omitted when only one or two positive sentinel nodes are identified, surgeons may no longer need to wait for frozen section or imprint cytology results before completing the operation, thereby substantially improving operating room efficiency.
4. Improving upper-limb function and quality of life
SENOMAC clearly demonstrated significant improvements in upper-limb function and lymphedema-related quality of life following ALND omission.
Therefore, from both physicians’ and patients’ perspectives, publication of the trial’s primary endpoint will further accelerate implementation of axillary de-escalation in China.
Q3. Oncology Frontier: Patient-reported arm morbidity—including lymphedema, shoulder dysfunction, and chronic pain—was another major focus of this presentation. Were the differences between the two groups clinically meaningful? Does this demonstrate that axillary de-escalation not only preserves oncologic safety but also substantially improves quality of life?
Professor Jana de Boniface:
I believe the primary goal of reducing axillary surgery has always been to lessen treatment burden while maintaining excellent survival outcomes.
Today, our patients live much longer, so we should strive to minimize long-term complications.
In SENOMAC, we assessed arm symptoms using the EORTC QLQ-BR23 questionnaire and observed highly significant—and clinically meaningful—differences between the treatment groups.
Across all four assessment time points, extending to five years of follow-up, differences in arm symptom scores consistently exceeded 10 points, which is generally considered a clinically meaningful threshold.
We also observed improvements in overall health-related quality of life shortly after surgery and again at three years among patients who omitted ALND.
Unlike some previous studies, however, although we observed statistically significant improvements favoring omission of ALND, I would be cautious about interpreting every statistically significant difference as necessarily being clinically meaningful.
Q4. Oncology Frontier: SENOMAC demonstrated clinically meaningful improvements in arm symptoms and physical function among patients who omitted ALND. In your experience treating Chinese patients, how common are postoperative lymphedema, shoulder dysfunction, and chronic pain? Are these patient-reported benefits sufficient to give clinicians greater confidence in de-escalating axillary surgery?
Professor Yongsheng Wang:
In addition to oncologic endpoints such as overall survival, disease-free survival, and breast cancer-specific survival, one of SENOMAC’s greatest contributions is its comprehensive evaluation of patient-reported quality of life.
Across multiple domains, the study demonstrated that omission of ALND significantly improved arm symptoms, physical functioning, and overall quality of life.
These benefits are highly meaningful for patients.
Traditionally, 25–30% of patients undergoing ALND develop upper-limb lymphedema, with approximately 10–15% experiencing severe lymphedema that can substantially impair daily function and quality of life.
Upper-limb lymphedema remains the complication with the greatest long-term impact, although shoulder dysfunction and chronic pain also remain common following ALND.
The quality-of-life findings from SENOMAC therefore provide greater confidence—not only for physicians but also for patients—in choosing axillary de-escalation when appropriate.
The Chinese Anti-Cancer Association Breast Cancer Committee has developed both professional and patient versions of its Guidelines for Standardized Sentinel Lymph Node Biopsy in Breast Cancer.
The patient-oriented version clearly explains that replacing ALND with sentinel lymph node biopsy significantly reduces postoperative lymphedema, shoulder dysfunction, and chronic pain.
Publication of the five-year patient-reported outcomes from SENOMAC will undoubtedly encourage both clinicians and patients to omit ALND in carefully selected individuals with low axillary tumor burden, defined as one or two positive sentinel lymph nodes.
Q5. Oncology Frontier: The ongoing SENOMAC-ULTRA trial is exploring an even more challenging question—whether ALND can be omitted in patients with clinically node-negative disease but imaging-confirmed axillary metastases. Looking ahead, what do you believe is the ultimate direction of axillary management? Are we moving toward an era in which even clinically node-positive patients may avoid ALND? What roles will targeted axillary dissection and regional nodal irradiation play?
Professor Jana de Boniface:
I believe we are moving away from an era in which almost every patient underwent complete axillary dissection toward one characterized by more precise and individualized surgery.
Our goal is to remove only the lymph nodes that provide the most clinically relevant information rather than removing every node, thereby preserving as many healthy lymph nodes as possible.
At the same time, surgeons must continue to provide the nodal staging information that medical oncologists rely upon when selecting systemic therapies.
The SENOMAC-ULTRA trial represents the next step in this evolution. It includes patients with clinically node-positive disease identified by imaging and aims to remove the known metastatic node together with the sentinel lymph nodes, thereby reducing nodal tumor burden without removing every metastatic lymph node.
Multiple clinical trials have already demonstrated that complete clearance of every involved lymph node is often unnecessary.
I believe the future of axillary surgery will be increasingly limited, precise, and individualized, with every effort focused on minimizing treatment-related morbidity while maintaining excellent oncologic outcomes.
Professor Yongsheng Wang
Shandong Cancer Hospital
Professor Jana de Boniface
Capio St. Göran’s Hospital, Stockholm, Sweden
