Lack of Awareness
By Chuck Green
Radiology Today
Vol. 20 No. 9 P. 22

Proton therapy shows promise and value for many cancers, but hurdles to wider use remain.

Proton therapy uses particles to deliver a highly concentrated amount of radiation to a cancer target. Because of its physical properties, the particles don’t impact surrounding organs to the same degree as conventional X-rays. Proton therapy also allows patients who receive radiation and experience a recurrence of cancer to be treated with additional radiation, offering the potential for controlling the disease without unacceptable complications to nearby organs, explains Dennis Mah, PhD, physics director at the ProCure Proton Therapy Center in Somerset, New Jersey.

Although the technology behind proton therapy continues to improve relatively rapidly, “it’s not as mature of a technology as X-ray-based radiation, in which billions of dollars of research and development has been invested over decades,” says Brian C. Baumann, MD, an assistant professor of radiation oncology at Washington University School of Medicine in St. Louis.

Baumann is the first author of a study led by Washington University School of Medicine and the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. The study is the first major side-by-side comparison of side effects related to proton therapy vs X-ray radiation therapy. It includes almost 1,500 patients receiving combined chemotherapy and radiation therapy for lung, brain, head and neck, gastrointestinal, and gynecologic cancers that had not yet spread to other parts of the body. Such patients receive both radiation and chemotherapy, a treatment regimen that often cures nonmetastatic cancer.

The study found that, even with reduced side effects, proton therapy resulted in cure rates similar to those of X-ray radiation therapy. “Cancer outcomes and overall survival outcomes were just as good with the proton therapy and, if anything, slightly better,” Baumann says. “But, systemically, there was no difference between the two.”

Historically, proton therapy has been used in various clinical situations, such as treating pediatric patients, as well as those with chordomas, Mah says. A chordoma is a rare type of cancerous tumor that can occur anywhere along the spine, from the base of the skull to the tailbone. Chordoma patients can be given a higher dose with higher conformity to the tumors than can be achieved with standard radiation, he adds.

Proton therapy has significant benefits in pediatric cancers due to a high rate of curability, remaining lifespan, and the added cost of side effects over time from standard radiation therapy in developing tissues, according to the National Association for Proton Therapy.

“If you have a child who is, let’s say, 5 years old, arguably, they have 80 years of life to develop a secondary malignancy from radiation,” Mah says. “If you can minimize the radiation that comes from the exit dose, we minimize the potential for those complications.”

Spreading the Word
According to the Mayo Clinic, proton therapy is not widely available in the United States. There are 31 proton therapy centers operational across the United States, with another scheduled to open soon. Florida leads the way with four, according to The National Association for Proton Therapy. “While this may seem like significant growth, it works out to be roughly 1.5 centers per year, which pales in comparison to the more than 2,300 standard radiation therapy facilities in the United States,” says Scott Warwick, executive director of the association. Additionally, eight more centers are under construction. To date, more than 200,000 patients have been treated.

Another issue is resistance among some payers to authorize proton therapy services for their members. “There also appears to be a difference of—and I think it’s opinion, rather than fact—regarding different members of the medical community, and I think that comes down to the haves and have nots,” says Andrew Lee, MD, an oncologist and the medical director of the Texas Center for Proton Therapy. In other words, he explains, “If you have a proton center and have experience with proton therapy, you’re likely going to be an advocate for it; if you don’t have proton therapy, or are competing against a proton therapy center, you’re less likely to be an advocate for it.”

In fact, Lee says it’s not really even a matter of reimbursement. “If it gets authorized, it will be reimbursed,” he says. “The issue is whether a payer will even choose to authorize the services. I think it depends on multiple factors, like the payer, the region of the country, and the case.”

Typically, reimbursement is most challenging with private insurers, especially if they lack a policy for the specific clinical situation for which they’re asked to approve the use of proton therapy, Baumann says. “In that case, we usually have to go through an appeals process, which requires letter writing, phone calls, and, often, a comparison plan between a proton therapy plan and conventional X-rays to demonstrate the reductions in radiation doses to crucial organs,” he explains.

Even then, it’s uncertain whether the appeal will be successful. “So, we invest a lot of time in trying to pursue what we think is the best treatment for our patients,” Baumann says.

Is that a cycle that can impact the use of proton therapy? “Sure; it’s very limiting,” he says. “It makes it hard to do clinical trials and hard for us to generate the data to see whether proton therapy is actually better [than conventional X-rays]. Every insurance company has a slightly different policy, so there are some, like United Healthcare, who now approve the use of protons for prostate cancer. That’s a big win, but most other insurance companies don’t follow suit.”

Awareness—among providers as well as patients—is another sticking point. “While it has improved, the medical community is further trying to upgrade the level of awareness of the therapy,” Lee says.

Last year, the National Association for Proton Therapy held its sixth annual conference to raise awareness of the therapeutic benefits of proton therapy among patients, providers, payers, policymakers, and other stakeholders. Goals included ensuring patient choice and access to affordable proton therapy as well as encouraging cooperative research and innovation to advance the appropriate and cost-effective utilization of proton therapy. The annual conference allows proton centers from across the United States to convene and discuss how to advance awareness of the clinical benefits of proton therapy for cancer patients, provide education, and advocate for insurance coverage.

Cost vs Value
The expense of the technique is also a hurdle, Baumann notes. “Equipment costs more and planning each treatment is more labor intensive and complicated,” he says. It’s significantly more expensive to purchase a proton unit than an X-ray machine—on the order of millions of dollars more expensive—and treatment is more labor intensive and complicated, he says.

Because of the specialized equipment and expertise needed to run the equipment, proton therapy can cost four to seven times more than traditional radiation treatments, according to Without insurance, the cost of the therapy can range from $30,000 to more than $135,000. In addition to the equipment, engineers are required to ensure everything is running and calibrate and test the equipment 24 hours a day, according to Robert D. Ferre on the Proton Beam Therapy website.

According to the findings of the American Cancer Society, Medicare pays about $19,000 for a full dose of standard radiation but more than $32,000 for proton therapy. Additionally, Ferre indicates that, while still significant, the cost of a three-room proton therapy center has gone down in the past five years from the $150 million to $200 million range to less than $100 million. Single-room treatment centers cost around $25 million.

There is some evidence, however, that the cost of therapy is not prohibitive. A study from Scripps that used Medicare reimbursement codes to compare the cost of proton therapy vs eight types of partial and whole breast irradiation therapies and treatment schedules for early-stage breast cancer patients found that proton therapy is at or below the cost of other therapies.

The cost of proton therapy, when used for accelerated partial breast irradiation to decrease overall treatment time and toxicity, was estimated at $13,833, according to the study, which was conducted by The University of Texas MD Anderson Cancer Center in Houston. By comparison, whole breast irradiation using intensity-modulated X-ray radiation therapy totaled $19,599, the highest Medicare charges. Across all of the eight treatment regimens investigated, the average charges were $12,784. That suggests the cost of proton therapy is similar to other types of radiation.

“We’ve known that proton therapy for breast cancer patients is an effective treatment that minimizes the impact of cancer therapy on patients’ daily lives, as well as the promise it holds for a healthier future for patients compared to other radiation treatments,” says Huan Giap, MD, PhD, of the Scripps Proton Therapy Center. “That it offers such advantages for patients at a cost that’s at or below the cost of other radiation treatments is further validation of proton therapy’s value.”

One factor that has helped tamp down the cost of proton therapy is the development of one-room centers, which has translated into the dramatic drop in the cost of proton therapy equipment, Warwick says. Compared with multiroom centers, which have often been standalone facilities that include not only the treatment rooms but the medical office space needed to support them, one-room centers are now being added to existing cancer center facilities that already have medical office space in place, he continues. Consequently, a multiroom standalone facility may have cost in the range of $100 million to $150 million in the past, but a one-room addition to an existing facility may cost in the range of $20 million to $40 million, based on the location, space required, and the equipment selected, Warwick says.

Signs of Growth
Despite these challenges, there are signs that proton therapy may assume a somewhat larger role in cancer care. According to the National Association for Proton Therapy annual provider survey, over the last five years, the proton therapy field has experienced tremendous growth in the diversity and number of cancer indications treated. The largest percentage growth has been in head and neck, gastrointestinal tract, and breast cancers, while prostate cancer has seen the slowest percentage growth. Pediatric cancer remains one of the most treated indications during this same time period.

Looking ahead, Mah recently attended the Particle Therapy Co-operative Group Annual Meeting, where he says there was “significant excitement” about a form of treatment called FLASH. He described it as “speculative” at this point, noting that the “experiments that have been done are sparse and it is still preclinical at this stage.” That said, he recounts discussions focusing on tumors receiving radiation at much faster rates than “what we have been using. You would be able to achieve the same level of tumor control with potentially fewer complications,” Mah says. “[To date, we] have varied both the daily dose and the total dose, but not the dose rate. That’s new.” Preliminary work has been done to ascertain whether this can be done with protons, he notes.

Baumann adds that his study points to instances in which patients are given a combination of chemotherapy and radiation simultaneously, which he calls “a very compelling and exciting” area. “Those are some of the sickest patients we see in radiation oncology,” Baumann says. “They’re getting the side effects of chemotherapy and radiation.” The hypothesis of his study is that, by limiting the amount of normal tissue exposed to clinically significant doses of radiation and chemotherapy with proton therapy, “we might be able to limit the risk of the side effects.”

— Chuck Green is a freelance writer based in Chicago.