Harold Abella

It's quick, safe, and relatively painless, and if interventional radiologists want to own it, they'd better step up quickly: Endovenous laser treatment of varicose veins is poised to take off, according to researchers at Cornell University. A two-year follow-up of 97 treated limbs showed a 6% recurrence rate, compared with 10% or higher recurrence that was reported for surgery, radio-frequency ablation, and transcatheter sclerotherapy.

The U.S. study was presented at this year's 15th annual International Symposium on Endovascular Therapy. It showed that laser treatment can be performed in an outpatient setting.

"Most of the people qualified to perform this procedure should be interventional radiologists, but over the next couple of years there will be thousands of physicians doing it, including vascular and general surgeons and even dermatologists," said Dr. Robert Min, coauthor and director of Cornell's new vascular center.

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Varicose veins may be setting of next turf war

Minimally invasive techniques for treatment of varicose veins show good long-term success rates, according to studies presented at the Society of Interventional Radiology meeting in Salt Lake City.

A three-year study by Cornell University researchers included 499 limbs from patients who underwent endovenous laser therapy (EVLT). Two-year follow-up results of the first 121 limbs showed a 93% success rate. The study also found that most recurrences of varicose veins took place during the first nine months following the procedure. No serious complications were reported.

Varicose veins are caused by reflux within the greater saphenous vein that leads to pooling in the visible varicose veins below. The laser therapy uses heat to close the greater saphenous vein. Deprived of blood, the visible varicose veins shrink and disappear, and other healthy veins reestablish normal flow.

Investigators applied strict criteria to establish whether the procedure had been clinically successful, said principal investigator Dr. Robert J. Min, vice chair of radiology at Weill Cornell Medical College in New York City. Patients underwent follow-up with duplex ultrasound one week after the procedure and at intervals of one, six, 12, and 24 months to verify that the saphenous vein remained closed.

Although clinicians expect further validation, the procedure is quickly catching on among patients, according to Min, who helped develop the technique. Traditional treatments, such as vein stripping or ligation, are invasive and require general anesthesia and hospitalization. FDA-approved EVLT is minimally invasive, can be performed on an outpatient basis, and requires only local anesthesia.

"The safety and efficacy have already been established," he said. "We need now to increase the number of physicians trained in this procedure to meet the demand from patients."

In another study, researchers at Memorial Sloan-Kettering Cancer Center also in New York City used radio-frequency ablation to treat symptomatic greater saphenous vein reflux in 139 limbs of 124 patients. After follow-up with ultrasound at four to six weeks, six to 12 months, and 12 to 24 months, they confirmed that the greater saphenous vein was closed in 95.7% of the treated limbs.

Both studies support the trend in medicine to replace existing procedures with less invasive, equally effective therapies, said Dr. Howard Chrisman, vice chair of clinical operations at Northwestern University's interventional radiology section.

"Often such procedures are less painful, performed in an outpatient setting, and well accepted by the patient. Indeed, over 98% of the patients in Dr. Min's study would recommend this to a friend," said Chrisman, who presented an independent review of Min's work for the SIR.

The overall cost-effectiveness for any one procedure is difficult to assess. Moving to the outpatient setting, however, will have varied implications. Patients can be treated at the interventionalist's practice, making it more accessible.

Long-term data favor varicose vein therapies

After four decades of experimenting with alternatives to surgical resection of tumors, researchers worldwide agree on several points: There is no silver bullet, but CT-guided radio-frequency ablation stands out among minimally-invasive therapies.

"Based on retrospective comparisons in matched patients, it is quite clear that in selected cases, such as cirrhotic patients with limited hepatocellular carcinoma, radio-frequency ablation can achieve the same or even better results compared with resection," said Dr. Riccardo Lencioni, a professor of diagnostic and interventional radiology at the University of Pisa, Italy.

Interventional radiologists on both sides of the Atlantic continue to debate what the preferred approach should be when surgery must be ruled out. Most, however, agree that RFA takes the lead in overall availability, cost-effectiveness, and efficacy.

RFA is the most widely used technique for ablation of focal liver lesions and the most powerful among percutaneous modalities when a single-needle electrode is used, said Dr. Luigi Solbiati, chief of radiology at the General Hospitals of Busto Arsizio, Italy. It can also be applied for ablation of kidney cancers, adrenal masses, lung cancers, bone lesions, and other tumors.

Alternative techniques, including percutaneous ethanol injection (PEI), microwave ablation, cryotherapy, and laser-induced thermotherapy (LITT), also vie for recognition in this arena, and for their own niches as well, according to Solbiati.

Cryoablation is slowly evolving from an intraoperative technique to a percutaneous option. Like RFA, its application is expanding from liver and kidney lesions, where it is known to be effective, into those affecting the lungs, bones, and spine. Unlike RFA, it is also considered relatively invasive.

Many studies have found that microwave ablation is faster than RFA and just as cost-effective and powerful, but it does not perform as well in small lesions. The same holds true for PEI, which is primarily employed for liver cancers when the other techniques are too expensive or not available. In many European countries, PEI is used not only for ablation of small hepatocellular carcinomas, but also for hyperfunctioning thyroid nodules, parathyroid tumors, and neck adenopathies from thyroid papillary cancer.

Recent studies in Germany have reported that LITT is useful to treat focal liver lesions using multiple fibers simultaneously, and it is effective in small lesions of the abdomen and the neck. But more trials are needed to validate findings, according to the authors.

Ultrasound, MRI, and CT all play roles in guiding various procedures. The preferred approach depends mainly on experience, real-time effectiveness, availability, and patient comfort.

"The best suited and the most widely used modality for guiding RFA procedures is CT, regardless of which organ is targeted," said Dr. Philippe L. Pereira, an associate professor of radiology at Eberhard Karls University in Tubingen, Germany.

Sonography is also reliable for needle placement but has visualization disadvantages, Pereira said. MRI-guided RFA offers multiplanar control, better tissue contrast, and near-real-time monitoring, but it is also time-consuming and more expensive than CT-guided RFA or cryoablation.

CT or ultrasound-guided RFA procedures are generally faster, but MRI-guided cryoablation provides a better visualization of the "icing" effect and can allow monitoring of the temperature of the organs, according to Dr. Eric vanSonnenberg, an interventional radiologist at Brigham and Women's Hospital.

"With CT or ultrasound, you know where the probe is, but you cannot actually see the effects of ablation on the tissue. MRI-guided cryoablation procedures are not widely available, however, and they are expensive," vanSonnenberg said.

Although most researchers agree that percutaneous thermal ablation techniques are cost-effective, no reliable data exist to support their superiority over surgical resection of tumors.

"There's been no controlled study to prove that assertion. Most of the studies have been done by individual centers, and none of them is randomized," said Dr. Gerald D. Dodd III, chief of radiology at the University of Texas, San Antonio.

RF ablation tops nonsurgical tumor treatment options

It's quick, safe, and relatively painless, and if interventional radiologists want to own it, they'd better step up quickly: Endovenous laser treatment of varicose veins is poised to take off, according to Cornell University researchers. A two-year follow-up of 97 treated limbs showed a 6% recurrence rate, compared with 10% or higher recurrence reported for surgery, radio-frequency ablation, and transcatheter sclerotherapy.

The study was presented in January at the 15th Annual International Symposium on Endovascular Therapy.

Approved by the FDA in January 2002, laser treatment can be performed in an outpatient setting and is less expensive than surgery, with little reported patient discomfort.

"Most of the people qualified to perform this procedure should be interventional radiologists, but over the next couple of years there'll be thousands of physicians doing it, including vascular and general surgeons and even dermatologists," said Dr. Robert Min, coauthor and director of Cornell's new vascular center.

Varicose veins: next turf war?

Radio-frequency ablation has evolved from a mere palliative measure to standard procedure for treating unresectable liver tumors. Research presented at the 2001 RSNA meeting suggests it eventually may replace surgery altogether.

Authors from the U.S. and abroad touted the benefits of RFA alone or in combination with other percutaneous therapeutic techniques, such as microwave coagulation, acetic acid and ethanol injection, cryoablation, or chemoembolization. Despite the promising results, however, RFA remains a difficult sell to specialists in other fields who want to see hard data.

"When you move outside radiology and discuss it with pathologists, oncologists, and surgeons, what they want to see are survival rates, among other things," said Dr. Riccardo Lencioni, a radiologist at the University of Pisa in Italy.

Two-thirds of the audience at one of the RSNA's gastrointestinal sessions validated the procedure as safe and accurate when the floor was opened for discussion. Almost unanimously, they said RFA was their interventional procedure of choice in treating patients with liver cancer.

Improved survival data should make the procedure easier to promote. In a study presented by Dr. Tito Livraghi, chief of radiology at Vimercate in Milan, Italy, the survival rate observed for one, three, and five years, respectively, was 95%, 81%, and 70% for RFA combined with other therapies.

A team lead by Lencioni compared RFA with percutaneous ethanol injection (PEI) in the treatment of hepatocellular carcinoma (HCC). The Italian researchers assessed 102 patients with solitary HCC smaller than 5 cm or a maximum of three lesions 3 cm or smaller. They found that RFA and PEI have a similar short-term survival rate, but RFA is superior for local recurrence-free survival.

Researchers from France and Germany also presented work on other ablation techniques, including good results with CT-guided direct application of a new cisplatin/epinephrine gel to ablate unresectable liver tumors.

RFA and other percutaneous therapeutic techniques should be considered complementary to one another in order to obtain better survival rates than those obtained with single treatments, according to Livraghi. Although RFA's long-term survival rate and statistical predominance over other therapies in the treatment of unresectable liver tumors make some radiologists consider it an alternative to surgery, he pointed out the necessity of careful selection and combination of therapies.

When experienced surgeons are confident they can perform anatomical resection of a single tumor without mortality, surgery is still the best option. But the number of surgeons known to Livraghi who can guarantee this kind of result is very small.

"I believe that radiological treatments are better," he said.

On a more cautionary note, specialists such as Dr. Gerald Dodd, chair of radiology at the University of Texas, San Antonio, and one of the moderators at the RSNA's gastrointestinal sessions, believe that better evidence is needed before considering RFA a replacement for surgery.

"There are neither enough hard data nor randomized trials to maintain that RFA is as good as surgery," Dodd said.

Percutaneous therapies show success, but more research is needed on long-term outcomes

Patients treated with radio-frequency ablation in conjunction with chemotherapy show significantly better survival rates than those receiving chemotherapy alone, according to a report presented at the RSNA meeting on Friday.

The study, conducted by Dr. Alice R. Gillams of Middlesex Hospital in London, U.K., included 190 patients with liver metastases selected from a pool of 358 patients originally diagnosed with colorectal cancer.

From this group of 190 patients, 90 had been treated with RFA and chemotherapy and 49 with chemotherapy alone. The remaining 51 underwent surgical resection or laser therapy.

Patients were divided into an optimal group with fewer than six metastases of less than 5 cm and no extrahepatic disease, and a nonoptimal group with six or more metastases, lesions larger than 6 cm, or extrahepatic disease.

Median survival rates were 33 months for patients undergoing RFA plus chemotherapy versus 18 months for chemotherapy alone. Survival for patients in the optimal group who received RFA and chemotherapy was 42 months with a five-year survival rate of 41%.

In the nonoptimal group, patients who had combined RFA/chemotherapy had a median survival rate of 31 months, while those treated with chemotherapy alone had a survival rate of 20 months. Chemotherapy results in this group surpassed those in previously published data, according to Gillams. More randomized controlled trials will be necessary, however, to compare both treatment approaches in patients with limited disease, she said.