In a randomized trial, published in The Lancet Oncology, Mayo Clinic Comprehensive Cancer Center researchers uncover evidence supporting a shorter treatment time for breast cancer patients. The study compared two separate dosing schedules of pencil-beam scanning proton therapy, the most advanced type of proton therapy known for its precision in targeting cancer cells while preserving healthy tissue to reduce the risk of side effects.
Prior to this study, all patients treated with proton postmastectomy radiotherapy (PMRT) had received a conventional 25- to 30-day course delivered five days per week over five to six weeks. The researchers hoped to demonstrate that condensing the course of proton beam therapy, a form of particle therapy that could spare the heart and lungs from radiation damage, may result in a similar side effect profile.
Eighty-two patients with indications for PMRT, many of whom had prior breast reconstruction, were randomized to either conventional fractionation (fractions of radiation dose) administered in 25 days, or a condensed 15-day hypofractionated schedule. With hypofractionation, a larger dose of radiotherapy is delivered with each treatment, allowing all radiotherapy to be completed in just three weeks. The investigators found that both conventional and hypofractionated proton therapy resulted in excellent control of the cancer while sparing surrounding normal tissue. Further, complication rates were comparable between the two study groups.
Importantly, the researchers noted that the new schedule spares patients additional inconvenience, cost, and other burdens associated with the longer regimen.