Aaron W.P. Maxwell, PGY3, Brown University
1. We now have long-term outcome data for patients treated with radiofrequency ablation for solid renal masses, with disease-free survival rates comparable to those among patients who undergo partial nephrectomy in multiple studies. Similarly, a large trial comparing ablation and surgical resection for hepatocellular carcinoma found no difference in overall and disease-specific survival for tumors ≤ 3 cm. With these data in mind, do you foresee ablation treatments becoming more visibly incorporated into formal treatment guidelines for these and other cancers?
The history of medicine is replete with examples of less invasive therapies replacing more invasive therapies (e.g. laparoscopic surgery or endovascular aneurysm repair). Some of the barriers in ultimate utilization from most important to least are: efficacy, economics, and both national and local politics. If a treatment is as or nearly effective (due to favorable underlying tumor biology) as a more invasive alternative adoption, then it is likely to occur overtime in select populations. If the cost of the new procedure is less than the more invasive alternative or any increased upfront costs can be justified by improved quality measures then utilization will be likely (e.g robotic-assisted prostatectomy). If the procedure is competitive with an existing, more invasive, longstanding alternative from a different specialty, then adoption can be slowed due to political pushback between specialties, though ultimately scientific evidence should prevail. In the case of image-guided tumor ablation of early-stage renal cell carcinoma, the efficacy and economic data are compelling despite the lack of randomized controlled trials. As a physician who has been treating renal cell carcinoma with ablation for nearly 20 years, what was initially an outrage—and then only a last resort measure—has now become a first-line option for many patients. As a wise man once said “scientific progress occurs one funeral at a time” or, in a modern sense, one retirement at a time. To many young (and some old) urologists I am a doyen in the treatment of stage 1 RCC and yes, if we are represented and share our voice on these treatment guideline committees, we will bring about incorporation and change.
2. Ablation treatments have historically been reserved for patients that are not optimal candidates for surgical resection. However, given the very low morbidity and mortality of percutaneous treatments, an argument can be made that treatments like ablation are in fact ideally suited to younger, healthier patients with longer life expectancies. Do you think we will ever see a shift in this direction, with a decreased focus on comorbidities?
The key to making image-guided tumor ablation first-line therapy in all patients is long-term outcome data. Unfortunately, this data takes decades to accumulate and until we have perfected our local control to the level of surgical techniques with improvements in planning, ablation, and validation technology, we will always be second in younger healthy populations who could live long enough to die of their recurrences.
3. Interventional radiology has been incredibly successful since its inception in bringing new diagnostic and therapeutic interventions into routine clinical practice. For various reasons, however, many of these procedures have ultimately migrated over to other specialties (e.g. peripheral vascular disease interventions and vascular surgery). Some non-radiologist practitioners current perform ablations, typically intraoperatively; do you see this trend continuing? Can you envision a future in which ablation is no longer performed predominantly by radiologists?
It is natural for specialists who control certain patient populations to adopt newer treatment techniques to stay current in the best treatments for their patients. This is what has taken place in vascular surgery. As surgeons, gastroenterologists, pulmonologists, and interventional radiologists evolve to meet the new demands on their specialties that these new minimally-invasive technologies create, they must understand that whomever is the most skilled at a certain procedure is the one who should be performing it. That being said the most efficient and comprehensive manner to treat a cancer patient is within a treatment team or pod. As interventional radiologists, we provide a valuable skill set to these organ-specific treatment teams and as long as we maintain our skill-set and involvement we have an important role in cancer care. However, I could envision an interventional oncologist of the future as a hybrid minimally-invasive surgeon and interventional radiologist. The creation of such a training program, however, would take considerable thought and may be difficult due to the years it would take to complete such a diverse training program.
Damian E. Dupuy, M.D., F.A.C.R. is a Professor of Diagnostic Imaging at The Warren Alpert Medical School of Brown University and the Director of Tumor Ablation at Rhode Island Hospital.