Ultrasound technique forecasts renal cancer therapy success

Doppler ultrasonography with perfusion software and contrast agent injection can be used to predict which patients with metastatic renal cell cancer will respond to treatment with the antiangiogenic drug sorafenib, according to a study presented at the 2005 American Society of Clinical Oncology meeting in Orlando.

"This sonographic method is original. B-mode imaging of tissue, on the one hand, and the use of microbubbles in different colors and advanced dynamic flow, on the other hand, can be visualized simultaneously but independently," said lead author Dr. Bernard J. Escudier.

Escudier and colleagues from the Institute Gustave-Roussy in Villejuif, France, and from Bayer Pharmaceuticals in West Haven, CT, tested the imaging technique to measure tumor response in 30 patients with metastatic renal cell cancer. They were enrolled in a double-blind placebo controlled phase III study of sorafenib.

Researchers prospectively evaluated tumor vascularization with the unique imaging technique at baseline and after three and six weeks on sorafenib or placebo in patients with tumor targets accessible to ultrasound.

Two radiologists evaluated the percentage of contrast uptake in each tumor. Results with Doppler ultrasonography with perfusion software were compared against CT scan studies at six weeks and with progression-free survival.

Preliminary results showed a decrease in tumor vascularization in 10 of 28 patients at three weeks and in 10 of 25 patients at six weeks.

"Overall, the combination of a decrease in contrast uptake of more than 10% with a stability or decrease in tumor volume significantly predicts progression-free survival in renal cell cancer. These criteria seem to be particularly predictive of benefit in patients treated with sorafenib," Escudier said.

For more information from the Diagnostic Imaging archives:

Contrast-enhanced ultrasound achieves new breakthroughs

Ultrasound emerges as versatile molecular option