Multiprobe RFA cuts treatment time in half

November 30, 2005

Multiple electrode radiofrequency ablation systems can reduce treatment times by as much as 60%, according to a study presented at the joint RSNA/SIR Foundation Interventional Oncology Symposium.

Multiple electrode radiofrequency ablation systems can reduce treatment times by as much as 60%, according to a study presented at the joint RSNA/SIR Foundation Interventional Oncology Symposium.

The multiple electrode systems allow physicians to use the power created by the generator continuously. When the impedance level spikes, power is transferred to the next electrode. A physician can treat up to three separate lesions simultaneously or can use all three probes in a single large lesion.

Three RF probes can be used simultaneously to treat large tumors

and multiple lesions.

In a study of 14 patients with 34 lesions, Dr. Luigi Solbiati, chief of radiology at the General Hospitals of Busto Arsizio in Italy, used a multiple probe system to simultaneously treat two small malignancies. Lesions were between 0.9 cm and 2.6 cm in size. Complete ablation was achieved in 97% of cases.

In one patient with seven lesions, complete ablation was achieved in 48 minutes. For patients with only two lesions, complete ablation was achieved in as little as 10 minutes. Solbiati concluded that such systems can cut treatment time by as much as 50% to 60% compared with conventional single-probe systems.

In a separate study, early clinical data presented by Paul Laeseke of the University of Wisconsin Medical School indicate that physicians can use multiple probe systems to treat single large lesions and poorly localized tumors requiring a large zone of ablation. Retrospective analysis of 20 patients with 32 lesions found that physicians can use the systems to create large, customizable necrosis zones.

The Wisconsin team was able to ablate large tumors normally excluded from RFA. The largest tumor treated was 12.5 cm. Local control was achieved in 85% of patients, with a mean follow-up interval of 2.6 months. Ablation time per tumor was approximately 28 minutes.

Laeseke recommended that electrodes be closely placed and found greatest success with probes placed no more than 2 cm apart.

Both Solbiati and Laeseke label the multiple probe approach promising but caution that it is a first-generation system, which could benefit from more power and additional probes. Further study is recommended.