In terms of duration of treatment and cost, patients with early stage breast cancer may benefit from accelerated partial breast irradiation (APBI) with proton therapy versus whole breast irradiation (WBI), according to new research. The findings were presented at the inaugural North America meeting of the Particle Therapy Co-Operative Group (PTCOG), held at MD Anderson Proton Therapy Center in Houston, Texas.
In a cost-analysis study based on typical patient characteristics, researchers from The University of Texas MD Anderson Proton Therapy Center used Medicare reimbursement codes to analyze allowable charges for eight different types of partial and whole breast irradiation therapies and treatment schedules available to patients with early stage breast cancer. Taken together, these represent roughly 98% of the treatment options available to these patients.
The cost of proton therapy when used for APBI, introduced to decrease overall treatment time and toxicity, was estimated at $13,833. Comparatively, WBI using IMRT (x-ray) therapy resulted in the highest Medicare charges at $19,599. The average charges across the eight treatment regimens were $12,784; thus, proton costs were similar to that of other types of radiation.
“It is often suggested that trials of proton APBI are irrelevant due to the modality’s presumed high cost, but our data shows that this perception is false. Correcting this perpetual assumption is an important step in helping patients obtain the necessary health coverage to participate in clinical research,” said principal investigator Valentina Ovalle, MD, postdoctoral research fellow. “Further, we anticipate that because charges vary proportionately across payers, the estimated Medicare reimbursement costs likely reflect relative charges to other third-party payers.”
The American Cancer Society estimates that 232,670 cases of invasive breast cancer will be diagnosed this year. Early breast cancer (stage I or II) is the most common invasive breast cancer in the United States. With treatment, these patients generally have a good prognosis. Standard treatment approaches typically include breast-conserving surgery (BCS) followed by radiation therapy for the entire breast, which occurs 5 days per week, for up to 6 weeks, including 1 week of boost radiation to the area where the initial tumor was removed.
The role of APBI for early stage breast cancer is still being evaluated, but its intent is to deliver a highly effective dose of radiation while greatly reducing treatment time. It involves 10 treatments twice per day over 1 week. Further, on average it spares at least two-thirds of breast tissue from a full dose of radiation.
“The biggest drawback to WBI is that it is inconvenient, interrupting lives,” said Eric A. Strom, MD, also of MD Anderson.
APBI is delivered via two approaches: brachytherapy and external beam. Proton therapy is offered as a type of external beam APBI and, according to Strom, is unique in its ability to provide the full dose of radiation precisely to the tumor site and nowhere else, eliminating radiation to the remaining breast, lung, and heart. To date, research on proton APBI has shown effective tumor control, limited side effects, and good cosmetic outcomes.
“This cost analysis must be interpreted in light of clinical evidence for proton APBI, which while still in nascent stages, is promising,” said Ovalle. “The findings counter the presumption that proton APBI is so expensive that even excellent clinical results would be immaterial.”