Recent advances in the treatment of early breast cancer have revealed that omitting axillary lymph node dissection (ALND) does not harm patient outcomes—a significant shift towards less invasive management techniques. This emerging perspective aligns with a growing trend in oncology to minimize aggressive treatments that previously characterized breast cancer care, which often involved extensive surgeries, chemotherapy, and radiation.

Monica Morrow, MD, from Memorial Sloan Kettering Cancer Center, highlighted this shift at the recent San Antonio Breast Cancer Symposium. “The burden on patients has traditionally been immense,” she stated. “Through rigorous clinical trials, we have established that many patients can benefit from breast-conserving surgeries instead of mastectomies. Similarly, we can substitute ALND with sentinel lymph node biopsy (SLNB), apply reduced radiation doses, and utilize targeted therapies that may offer superior outcomes compared to standard chemotherapy.”

In particular, this strategy is relevant for postmenopausal women with hormone receptor-positive, HER2-negative breast cancer. Elizabeth Mittendorf, MD, PhD, from Dana-Farber Cancer Institute, discussed the criteria for potentially omitting axillary surgery, based on findings from the SOUND and INSEMA trials and other clinical practices.

Key Findings from SOUND and INSEMA Trials

The phase III SOUND trial evaluated patients with early breast cancer who had negative axillary ultrasounds, comparing SLNB with no axillary surgery. Results showed that about 13.7% of participants in the SLNB group had positive axillary nodes, but crucially, the five-year distant disease-free survival rate was approximately 98% for both groups—indicating that omitting ALND did not compromise patient safety.

Similarly, the INSEMA trial zeroed in on patients with clinically node-negative stage T1-2 breast cancer who were also randomized to SLNB or no axillary surgery. After nearly 74 months of follow-up, the invasive disease-free survival rate remained around 92% for both groups. Interestingly, although the no-surgery arm recorded slightly higher axillary recurrence rates (1% versus 0.3%), it paradoxically had fewer deaths (1.4% versus 2.4%).

Moreover, avoiding ALND was related to lower rates of lymphedema and pain, with significant benefits in terms of patients' quality of life. This supports recommendations from the Choosing Wisely campaign, which suggests that women aged 70 and older may safely forgo SLNB.

Real-World Evidence and Broader Implications

Mittendorf's research involving over 3,900 patients confirmed that a majority were node-negative, aligning with findings from the SOUND trial. In this cohort, less than 1% had four or more positive nodes, with a robust emphasis on hormone therapy as a primary treatment avenue.

The implications of these findings resonate throughout oncological communities. As raised by INSEMA investigator Toralf Reimer, MD, PhD, these practices can notably benefit women over the age of 50 with HR-positive breast cancer and small tumors. Discussions led by Puneet Singh, MD, emphasize the necessity of continuing SLNB as a staging modality for many patients due to the complexities of oncological treatment.

A Future of Tailored Treatments

As the landscape of breast cancer treatment evolves, establishing criteria for surgical staging becomes imperative. Dana-Farber's multidisciplinary groups have crafted specific guidelines, which include patient age, tumor characteristics, and clinical assessments of lymph node status.

In conclusion, as we navigate the complexities of breast cancer care, the results from SOUND and INSEMA empower clinicians to rethink the necessity of ALND. With ongoing research and collaboration, clinicians can develop personalized care plans that prioritize patient outcomes and quality of life, igniting a new era in breast cancer treatment. Stay tuned for more groundbreaking developments in the fight against breast cancer!