Dr Haffty on the Feasibility of Preoperative Radiation Boost in Breast Cancer

Bruce Haffty, MD, MS, chair, Radiation Oncology, associate vice chancellor, Cancer Programs, Rutgers Cancer Institute of New Jersey, system director, Radiation Oncology, RWJBarnabas Health, discusses the feasibility of utilizing preoperative radiation boost in patients with breast cancer based on initial results from a phase 2 trial (NCT04871516).

The prospective trial was launched to assess the safety and efficacy of delivering radiation boost prior to breast-conserving surgery, Haffty begins. This approach could allow for more accurate targeting of the high radiation dose of the tumor that may spare more normal breast tissue. Investigators also hypothesized that wound complication rates with this approach would be non-inferior to that of standard conventional lumpectomy, postoperative whole breast radiation, and a postoperative boost.

The study enrolled 55 women diagnosed with non-metastatic, node-negative breast cancer or DCIS who were eligible for breast-conserving therapy (BCT), Haffty states. Patients received pre-operative radiation in the form of a boost with a total dose of 1332 cGy delivered in 4 fractions, followed by lumpectomy and subsequent adjuvant hypofractionated whole breast radiation totaling 3663 cGy delivered in 11 fractions.

Of the 48 eligible patients, a single patient (2%) experienced grade 3 wound dehiscence necessitating surgical revision, with no other grade 3 adverse effects reported. Three patients (6%) experienced grade 2 wound infections necessitating antibiotics. Cosmetic assessment at initial follow-up, which was available for 45 patients, indicated very good or excellent outcomes in 39 patients (87%), with no instances of poor cosmetic outcomes. Furthermore, both patients and surgeons had a favorable view of this approach, Haffty emphasizes.

These results demonstrate that administration of a pre-operative radiation boost prior to lumpectomy followed by whole breast radiation is safe and feasible compared with the standard of care, Haffty states. A subsequent expansion cohort is currently enrolling patients to evaluate longer-term cosmetic results, and a panel of immunologic markers is being employed to assess the immune response to the preoperative boost, Haffty concludes.