Chinese interventionalsts use fresh techniques to improve outcomes

Chinese physicians are adopting interventional radiology techniques to treat vascular insufficiency and inoperable liver cancer.

Renal artery stenting is the first choice of most physicians and patients for treating renal artery stenosis. Interventional protocols are also widely accepted for treating hepatocellular carcinoma, according to Chinese interventionalists who spoke in September at the 2007 annual meeting of the Cardiovascular and Interventional Society of Europe.

Interventionalists in China are working to improve the results of their techniques. They are employing emboli protection devices to prevent distal embolization, which may be responsible for at least some of the 20% of cases of deterioration following renal artery stenosis. They also are using transarterial chemoembolization for both large and small HCC tumors.

Renal artery stenting is technically successful in nearly all cases of stenosis in China. The procedure has a patency rate of 90% at five years and produces acceptable levels of blood pressure control, according to Dr. Yinghua Zou, vice president of the Chinese Society of Interventional Radiology.

Distal embolization, which may be a principal cause of late stenting failure, is not easy to diagnose and has no effective treatment. Prophylactic measures involving careful case selection, gentle technique, small profile instruments, and the use of emboli protection devices are therefore essential, he said.

In a study of 67 patients who received emboli protection devices, 53 were stable at six months, and none had stent deterioration. At three and five years, the rates of deterioration were 2% and 7%, respectively. In Zou's experience with 106 patients, serum creatinine declined and there were no cases of deterioration in the protection device group. Creatinine increased, and three cases of deterioration occurred in the group that did not receive emboli protection devices.

In a study of 1000 patients with inoperable HCC, five-year survival was 12% following transarterial chemoembolization (TACE). Survival was much lower (2.6%) in those who had emboli in the portal vein, said Dr. J-H Wang from Shanghai Hospital.

"It is important to pay more attention to PV emboli. TACE can be done depending on the extent of the obstruction," he said.

TACE was particularly effective for small malignancies in the study. Among 880 patients who had HCC tumors larger than 5 cm, survival was 22% at five years. Five-year survival was 51%, however, in 120 patients who had smaller tumors.

The technique also allowed 92 patients to be surgically resected, which improved five-year survival to 63%.

For more information from the Diagnostic Imaging archives:

Renal artery revascularization procedures could damage kidneys

MR-guided laser therapy proves its worth in liver cancer mets

CT perfusion opens functional window to GI tumors

Commentary: Next phase of radiology will develop with developing world