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| “We have applied the technique to solid tumors throughout the human body.” —Damian Dupuy, MD Rhode Island Hospital |
Interventional radiologist Damian Dupuy, MD, is a self-described “pioneering zealot” in the application of radiofrequency ablation (RFA), especially when it comes to treating cancer patients. Web search oncologic RFA and Dupuy’s name links up everywhere. His list of publications on RFA cancer treatment takes up pages. His Rhode Island Hospital colleague, imaging director Stephen Hiss, calls Dupuy “the leader nationally” in the application of oncologic RFA.
Nevertheless, Dupuy still has to battle, even at his own hospital, to push the oncologic RFA program beyond the red ink and into the black. It is a measure of how difficult a new technology can be to roll out. It is also a mean fate for a treatment that is demonstrably adding months, if not years, to patients‘ lives and palliating the pain and suffering of many more, to whom quality of life is more than a catch phrase.
Dupuy, a graduate of the University of Massachusetts medical school, says he learned about cancer RFA first hand in the early 1990s when, as a resident at Massachusetts General Hospital, Boston, he assisted in applying the treatment to pediatric bone cancer, successfully ablating osteoid osteomas.
When he moved to Providence and Rhode Island Hospital in 1998, he extended the treatment to liver tumors. He then found that he also could successfully ablate many solid tumors, including kidney, lung, adrenal, pelvis, and head and neck cancers.
“We have applied the technique to solid tumors throughout the human body,” he says.
Essentially, RFA works by using radiofrequency waves to heat metallic probes—needles or similar multi-pronged devices—that have been inserted by the interventional radiologist (IR) directly into the targeted tumor. The heat in the probe destroys the tumor by cooking it. The insertion of the probe is guided by imaging, sometimes ultrasound but more often CT.
The technique has many advantages. Unlike chemotherapy, it has no adverse effect on the immune system; unlike radiation therapy (RT), it can penetrate to the center of a tumor and effectively destroy tissue where there is little or no oxygen, something at which RT can be ineffective. Of course, the patient also is spared the radiation exposure.
RFA is still enough in its infancy that it is rarely if ever used as a substitute for surgery, although Dupuy says that it may become a substitute for limited surgery with small, early cancers. Where RFA does take over the role of excision is in those many cases where the patient is too compromised by comorbidities to withstand surgery. This is a common scenario with lung cancer patients, Dupuy says, particularly smokers with emphysema or perhaps heart disease who may be not only too compromised for surgery but poor candidates for radiation therapy and chemotherapy too.
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But where RFA really shines—and where Dupuy and his colleagues are putting emphasis—is as a synergistic companion treatment to the other three cancer care arms: surgery, medical oncology, and radiation oncology. Of these three, RFA works particularly well as a companion to radiation therapy, Dupuy says.
“One of the main reasons radiation fails,” he says, “is because there’s not enough oxygen in the environment of the cancer. Radiation needs oxygen to work. Suppose there’s a tumor the size of a Ping-Pong ball. The cancer cells don’t die because the ionizing radiation needs oxygen to create free radicals, which causes cancer cell damage and cell death. So, suppose you remove all those hypoxic areas with RFA, then what’s left will be at the periphery and more suitable to radiation.”
RFA thermally destroys the heart of the tumor, and then radiation is used to bombard and kill the outer segments where the blood supply and oxygen are sufficient for cell death.
“We discovered that synergy and thought about it early on,” Dupuy says. “Surgeons add radiation to excision. RFA is like a limited surgery, so why not add radiation to RFA?”
The Fourth Arm
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At Rhode Island Hospital, Dupuy and his colleagues are deploying RFA as a fourth arm in cancer treatment, trying to give the patient an added option to battle disease.
“The interventional radiologist has become the fourth member of the [clinical] team that handles the patient,” Dupuy says, “particularly those patients who don’t respond to traditional therapy and are not able to have surgery.”
He says this team approach optimizes cancer care: “If you have a strong surgeon, a medical oncologist, a radiation oncologist, and an interventional radiologist, you are going to treat that patient more effectively. If you don’t have all four of those arms of cancer care, your system is going to break down, and that patient will have to go elsewhere. The majority of teaching hospitals have those elements now, including RFA. They may not be using it in every organ system, and they may not have complete integration in each of the member teams, but it is being used.”
In fact, Dupuy adds, it is common now for other subspecialists like surgeons and medical oncologists “to ask IRs to get involved with RFA.”
“The other three arms on the cancer care teams are getting educated,” he says, “and they come back and they go to interventional radiology. They say, ‘I just heard a great talk on RFA. Let’s try it.’ ”
Rhode Island Hospital, with its 719 beds and about 180,000 outpatient visits per year, is the major teaching hospital for Brown University’s Medical School. Dupuy is one of three IRs on the hospital’s staff of about 60 radiologists.
Since 1997, when the Food and Drug Administration approved RFA as a treatment, Dupuy and his colleagues have used the thermal process to treat more than 700 patients, he says. “We have our own tumor ablation service, and we provide ablation to all those doctors who have a cancer patient where the tumor can’t be removed surgically, or where the patient is too sick for, or hasn’t responded to, conventional treatment and they have symptoms to control.”
Teamwork
Thomas DiPetrillo, MD, is clinical director of radiation oncology at Rhode Island Hospital and Dupuy’s colleague.
“My specialty has been in bringing new technologies into the clinic, but a big part of that has been using them in a multidisciplinary fashion,” he says. “My biggest pleasure is working with surgeons and medical oncologists.”
DiPetrillo says he has worked closely with Dupuy to administer radiation therapies in conjunction with RFA. These have included high dose rate brachytherapy, in which DiPetrillo is an expert, joined with RFA to treat lung cancer patients.
DiPetrillo says RFA is now seen at Rhode Island Hospital as a partner technique in the treatment of cancer.
“We are seeing more and more applications and are becoming more comfortable in approaching different cancers with it,” he says. “It’s not uncommon to combine surgery, a partial hepatectomy, say, while another lesion in an opposite liver lobe might be accessed by radiofrequency ablation, and all metastatic disease destroyed surgically or thermally.”
Dupuy and his IR colleagues are part of the cancer care team that convenes weekly at tumor boards—a different disease site is chosen for review each week—where treatment is planned, DiPetrillo says.
“The IRs are most involved in the lung and gastrointestinal disease,” DiPetrillo says. “Everything is done prospectively through the boards, diagnosis, and management. People are putting their two cents in early.”
The teamwork is helped along by the physician mix at Rhode Island Hospital, DiPetrillo adds.
“What’s nice in our institution right now is that most of the physicians are of the same generation,” he says. “They are all in that category of having 7 to 15 years’ experience. The representatives from each of the specialties are in that somewhat experienced group, but they’re not in the dogmatic group. Everybody is given to the fact that we have these [tumor] conferences to come up with the best treatment plan.”
Although the teamwork is solid, he adds, the decisions on just how to treat certain patients and what to try with particular cancers can be agonizingly difficult. “The lines of treatment are not very clear, and then there are always the patient’s wishes,” he says. Treatment decisions often contain elements of doubt where other motives, like monetary profit and loss, can come into play, especially since the documentation of RFA through outcomes remains under study.
“There are always going to be turf battles. Thermal ablation is still a deviation from the standard of care,” DiPetrillo says. “But if people believe the standard of care carries risk, why not try thermal ablation? Has the patient lost anything? Probably not.”
Still, it is because of standard of care issues that many of the patients on whom RFA is used turn out to be those most ill and most compromised for alternative treatments. They are beyond the pale of standard treatments.
“I think there are longer disease-free intervals clearly with RFA,” DiPetrillo says. “Can we impact more cures or increase life spans? In time, we will know. The populations we have now are very limited. They’re not dying of their lung cancers; they’re dying of emphysema or heart disease.”
One study at Rhode Island Hospital where lung cancer patients received RFA followed by either external beam radiation or brachytherapy found that of 41 patients, 75% survived 2 years longer than expected.1 Of that group, the 17 patients with lung tumors of 3 cm or smaller had the best outcomes with RFA.
Even with documentation like this, Dupuy says there are other specialists with their own interests who can act as a drag on the RFA program’s expansion.
“Suppose you have a physician who does RFA and who says, ‘I can put my probe in that 1-cm lung cancer and kill it, and that may be all that patient needs.’ If the radiation oncologist sees only the lost revenue from that patient, they may not agree that RFA would be that successful. Let’s face it, they’ve got this big linear accelerator, and they have to support their own practice, so why send that patient elsewhere? They could argue that ‘it’s an interesting device,’ that RFA.”
Bottom Quartile
RFA, like any treatment, has limitations and best uses. Large tumors are difficult to ablate thermally. Metastasis, once it becomes virulent, may be too extensive to treat, Dupuy says.
“It depends on if ablation makes sense clinically,” Dupuy says. “If the natural history of the disease is longevity, it might make sense to zap what you see. But if what you see is the tip of the iceberg, then that’s not going to affect the quality of life with what you’re seeing today. You create tissue damage apart from the tumor, and you would run out of real estate before you created undue symptomatology with the patient, not to mention the pain and expense.”
Yet, Dupuy and the other IRs at Rhode Island Hospital have had success relieving pain and dyspnea in lung cancer patients, for instance, by ablating chest wall tumors and other cancerous structures. There is definitely a palliative role for RFA, Dupuy says. And just as RFA can be used in combination with radiation therapy, it can also be applied prior to chemotherapy to make that treatment more successful.
Dupuy says the applications for RFA and its use generally are just getting off the ground. Even so, he estimates that nearly all academic hospitals and 75% of private practice subspecialty radiology groups use RFA for some treatments.
“I think we’re still in the bottom quartile of applications and implementation,” he says. “I think worldwide, maybe 60,000 procedures were done in 2004, and the experts are saying it will grow 10% to 20% every year. When you talk about the Baby Boomers, who represent almost one quarter of the US population, that’s going to put a huge strain on the health care system. You will have a demanding and educated population wanting the most high-tech health care. We probably can’t afford that. We will have to use quick ablative techniques for cost efficacy.”
Smoking Baby Boomers particularly will boost the use of RFA to treat lung cancer in the future, he adds, another reason why making RFA one arm of treatment today may pay off even more in the future.
Breast cancer, it turns out, is problematic for the application of RFA.
“With breast tumors, the disease can be infiltrative and multifocal and that’s difficult to obtain on a core biopsy, but can be obtained on a lumpectomy specimen,” Dupuy says. “We need to improve breast MRI to find the extent prior to ablation, because when you do ablation, you don’t get a sample to look at. It’s unclear who would be a candidate for ablation, although if you had early, well-defined breast cancer and the imaging to prove it wasn’t multifocal, then you could probably do ablation with the same local control as a lumpectomy with the added cosmetic benefits.”
But the large amount of fatty tissue in the breast makes surgery low risk, so the fact that surgery is the standard of care—plus low risk—makes it difficult for RFA to make headway as a breast cancer treatment, Dupuy says. He says doctors in the breast imaging section at his own hospital have shown little interest in the procedure, despite his efforts to interest them.
Although he does not treat breasts himself, Dupuy says, for nonmalignant tumors, RFA could be a “no brainer.” Fibroadenomas, noncancerous breast tumors that particularly afflict African-American women, could probably be curtailed and their pain stopped “without a breast incision,” he says, yet another example of where RFA might have a role.
Learning RFA
Any certified IR is implicitly trained to perform RFA and would have little trouble learning the probe insertion techniques, Dupuy says. It is cancer they may not know about.
“The IR has the skill from the technical side,” he says, “but they need to be educated on the whole oncological disease process—and that comes with being part of the medical team. The medical oncologist and the thoracic surgeon educate you. You become expert through interacting. It’s very important to have that good relationship across specialties. It’s not hard to do as long as everybody is a willing team member, if your goal is to help the patient and do what’s best for them.”
RFA is not without risk. As Dupuy acknowledges, if too much heat is applied, tissue may char or fluids vaporize. If blood vessels cool tissue being ablated, residual cancer in those blood-cooled areas may survive and later spread.
Choice of probes is also a factor in the delivery of RFA, Dupuy notes, not just technically but economically. With one-time-use electrodes costing $600 to $2,000, choosing an expensive probe unnecessarily can impact the hospital’s bottom line, he says.
“If the electrode is $2,000, there isn’t much [profit] left for the hospital,” he says. “That particular [probe] vendor encourages admitting that patient overnight.”
To help IRs learn RFA, Dupuy conducts frequent workshops, which also contribute income to his Rhode Island Hospital program. He, DiPetrillo, and others have undertaken many studies to prove that RFA deserves to be a fourth arm in cancer care. Dupuy now is principal investigator in the American College of Radiology Imaging Network (ACRIN) trial 6661, a study of RFA to combat bone metastases, as well as as well as the American College of Surgeons Oncology Group (ACSOG) trial Z4033, a study of RFA to treat early lung cancer in poor operative candidates.
Money—The Bottom Line
Despite the advances made with RFA, it remains questionable as a money maker, at least at Rhode Island Hospital.
Dupuy says he thinks the program breaks even. “We did an ROI [return on investment] and found that RFA breaks even.” He says that in any event, the RFA program “creates considerable downstream revenue, because if you attract that cancer patient [through RFA], then all the follow-up increases the hospital’s revenue.” That follow-up could include imaging, surgery, or any of the alternate cancer treatments.
“I saw two patients yesterday, one of whom had a tumor I felt was better treated surgically,” Dupuy says. “That patient would not have been sent to our liver surgeon if I hadn’t seen them first. We are capturing more cancer patients by providing this service, which increases the other team services. I would say that for every patient we see, we send them for an added consult 50% of the time.”
But Dupuy’s perspective on the RFA program needs to be optimistic. It is his program.
Stephen Hiss is director of diagnostic imaging at Rhode Island Hospital. He may have a better view of the financial picture.
Hiss agrees that the RFA oncology program is evolving into “a team process that’s more involved with patient follow-ups and better outcomes.” And that has heightened the RFA oncology profile, he adds.
The problem is that payors do not yet want to spend money on RFA, and getting reimbursed for it is, in many cases, difficult or impossible, Hiss says.
“It’s the classic balance of a valuable service evolving into a situation that needs to be balanced against the overall cost of health care. That’s the universal problem in health care today,” he says. “It’s a classic balance between payors holding costs down and, at the same time, a new service coming on line that threatens the holding of that line. It’s a difficult process.”
Hiss says Medicare is one of the better payors when it comes to RFA reimbursement. But even for Medicare, not all the RFA procedures are approved, he adds.
Financially, he says, the RFA program is “having difficulty breaking even.” Hiss also notes another difficulty. Since the RFA interventionalists do not have a dedicated CT scanner, this puts pressure on IR to not tie up the scan room with RFA treatments.
“From a revenue perspective, you have to keep in mind that for some institutions where CT access is already difficult, the room time needed for these ablation procedures may limit the number of time slots that were previously available,” Hiss says.
Dupuy says he could spend all his time doing RFA oncology if he could take on the whole caseload of those patients who want it. For now, he says, he is doing RFA only 3 days a week and seeing only four to six new patients weekly.
Because reimbursement is difficult, Dupuy says, the hospital tries to wait for preapproval for RFA patients. “Otherwise, we will treat them and help in the appeal [to payors],” he says.
Hiss adds, “We have patient advocates who will work with patients to work out a payment plan that the patients think they can handle.”
Ultimately, Dupuy says he hopes the hospital will fund a “cross-platform suite” where RFA and other image-based treatment could be performed in one setting. Such platforms are being built elsewhere, he says. This would end the CT bottleneck that exists.
DiPetrillo also cites this as a goal, but he admits it would cost multiple millions of dollars. “We have requested it, and there are budgets submitted. We don’t know how far away we are from it.”
In the meantime, Dupuy keeps on with his zealotry, trying to make both physicians and the public aware of how beneficial oncologic RFA can be, hoping that reimbursement will follow.
“I don’t remember who said this, but scientific progress occurs one funeral at a time,” he concludes. “Eventually, this treatment will become widespread and the standard of care.”
George Wiley is a contributing writer for Axis Imaging News.
Reference
- Grieco CA, Simon CJ, Mayo-Smith WW, DiPetrillo TA, Ready NE, Dupuy DE. Percutaneous image-guided thermal ablation and radiation therapy: outcomes of combined treatment for 41 patients with inoperable stage I/II non-small-cell lung cancer. J Vasc Interv Radiol. 2006;17:1117-24. Available at: www.jvir.org/cgi/content/ abstract/17/7/1117. Accessed September 27, 2006.
