Limiting Surgery in Early-stage Breast Cancer

SOME PEOPLE with early-stage hormone receptor-positive, HER2-negative breast cancer can safely forgo sentinel lymph node biopsy, according to the results of a phase III clinical trial presented Dec. 11 at the 2025 San Antonio Breast Cancer Symposium.

Located throughout the body, lymph nodes filter lymph, a fluid that carries white blood cells. However, cancer cells use the lymphatic system to spread to distant parts of the body. In that process, cancer cells first spread to the lymph node closest to the cancer site, called the sentinel lymph node. To determine if cancer has spread beyond the initial site, people with breast cancer often undergo a sentinel lymph node biopsy. In this procedure, a surgeon injects a dye that drains from the tumor to the closest lymph node and then removes that node.

Sentinel lymph node biopsy results can help an oncologist understand whether the cancer might return and may indicate whether the patient should have additional surgery or radiation to the lymph nodes. The results typically do not impact what treatment patients receive, according to Marjolein Smidt, a surgical oncologist at Maastricht University Medical Center in the Netherlands, but people who undergo sentinel lymph node biopsy often experience scarring and lymphedema, a potentially long-term side effect where lymph buildup causes painful swelling, typically in the arms or legs.

Smidt and colleagues investigated whether people with a small breast cancer tumor who had no signs of lymph node involvement on ultrasound could avoid sentinel lymph node biopsy without compromising their risk for recurrence. The clinical trial evaluated 1,574 people who had a breast tumor smaller than 5 centimeters, 86.6% of whom had hormone receptor-positive, HER2-negative disease.

Participants received a lumpectomy and whole-breast radiation. Afterward, 749 people had sentinel lymph node biopsy and 825 skipped the procedure. In 86% of those who had the surgery, the sentinel lymph node biopsy results confirmed cancer was not present in the lymph node, so their treatment plan did not change.

Some participants had additional treatment: 17% received chemotherapy or targeted therapy and 44% took endocrine therapy. Both groups had similar follow-up treatment rates.

After a median follow-up of five years, 96.6% of people who had sentinel lymph node biopsy and 94.2% of those who did not get the surgery were alive without recurrence in the breast or nearby lymph nodes. “These findings indicate that omission of the sentinel lymph node biopsy may safely be considered” for people with early-stage hormone receptor-positive, HER2-negative breast cancer, Smidt said in a press briefing.

People who did not have sentinel lymph node biopsy reported better health-related quality of life than those who had the procedure, according to Smidt.

Smidt cautioned that the results may not apply to all people with breast cancer because trial participants received their treatment at 25 hospitals in the Netherlands between 2015 and 2022. Treatment in the Netherlands and the U.S. differs for early-stage breast cancer, with fewer people in the Netherlands receiving endocrine therapy after initial treatment for early-stage disease, Smidt said.

Additionally, participants in the trial received whole-breast radiation, which treats the entire breast. In the U.S., most people with early-stage breast cancer instead undergo radiation that targets a smaller area of the breast where the tumor is, which might affect the safety of forgoing sentinel lymph node biopsy. “We don’t yet know if it’s completely safe to omit the sentinel lymph node [biopsy] in the context of partial-breast irradiation in all cases,” said Gaorav Gupta, a radiation oncologist at UNC Lineberger Comprehensive Cancer Center in Durham, North Carolina, who was not involved in the study.

Since sentinel lymph node biopsy helps oncologists determine the extent of radiation treatment, most studies that examine the safety of partial-breast radiation in early-stage breast cancer involve people who have undergone the procedure. The evidence supporting partial-breast radiation is less clear in those who have not had sentinel lymph node biopsy, according to Isabelle Bedrosian, a surgical oncologist at the University of Texas MD Anderson Cancer Center in Houston who was not involved in the study. “It’s great that patients have options, yes, but it would also be nice as we move forward to try to find ways to integrate all of these different options,” Bedrosian said.

The post Limiting Surgery in Early-stage Breast Cancer appeared first on Cancer Today.