Dr Thompson on Trials Evaluating De-Escalated Treatment in Early-Stage Breast Cancer

Alastair Thompson, BSc, MBChB, MD, FRCS, professor, chief, Division of Surgical Oncology, Section of Breast Surgery, co-director, Lester and Sue Smith Breast Center, co-associate director, Clinical Research, Dan L. Duncan Comprehensive Cancer Center, Olga Keith Wiess Chair of Surgery, Baylor College of Medicine, discusses ongoing clinical trials investigating de-escalated treatment in the perioperative setting for patients with early-stage breast cancer.

During a presentation at the 23rd Annual International Congress on the Future of Breast Cancer® East, Thompson delved into the potential omission of surgery or other therapies in in patients with early-stage breast cancer, which including highlights of ongoing trials in this space.

The first trial Thompson mentions is the phase 3 HERO trial (NCT05705401), which is an ongoing randomized trial evaluating the efficacy of HER2-targeted therapy with or without radiation therapy in the adjuvant setting following breast-conserving surgery in patients with early-stage, low-risk, HER2-positive breast cancer. Specifically, the study is including patients with tumors less than 3 cm in size who have node-negative disease, Thompson says. All patients are undergoing neoadjuvant therapy and surgery prior to randomization, he notes.

Thompson also discusses the ongoing OPTIMIST trial (NCT05505357) being conducted in South Korea, which is exploring the omission of surgery in patients with early-stage breast cancer who have a pathological complete response to neoadjuvant therapy per MRI assessment and vacuum-assisted biopsy. Eligible patients could have HER2-positive breast cancer or triple-negative breast cancer, Thompson says. If no residual tumor cells are detected on a vacuum-assisted biopsy, breast surgery will be omitted. Patients will also be allowed to forgo sentinel lymph node dissection if they have clinical N0 disease, a tumor size of no more than 0.5 cm on MRI, and a lesion-to-background signal enhancement ratio of no more than 1.6. Axillary lymph node dissection can still be performed, if necessary. All patients will still receive radiation, Thompson adds.

Thompson explains that these trials could be important in potentially reshaping the future management of early-stage breast cancer. Results could provide insights into the feasibility and safety of omitting surgery or radiation therapy in select patient populations, ultimately contributing to more tailored and less-invasive treatment strategies, he concludes.