Although primary and secondary liver cancer is one of the most common forms of cancer around the world, most forms of therapy are at best only partly successful. An international group of interventional radiologists took a close look at some of the emerging minimally invasive techniques and discussed the advantages and drawbacks for treating these tumors.
The presentation earned the RSNA's summa cum laude award for scientific exhibits.
At the University of Texas Health Science Center in San Antonio, interventional radiologists are studying the use of radiofrequency ablation. Led by Dr. Gerald Dodd III, FACR, the team treats tumors with shielded needle electrodes that send a current into the malignant tissue. The friction of the current heats the tissue to over 50 degrees Celsius, killing it. Each ablation covers about 3 cm.
The generator for the technique costs up to $30,000, and the disposable needle electrodes each cost between $500 and $1000.
Patients can have up to four tumors, but none can be larger than 5 cm. Contraindications include sepsis, severe debilitation, or uncorrectable coagulopathies.
At Middlesex hospital in London, England, Dr. William R. Lees prefers laser ablation with a single bare 400-micron laser fiber. Light at optical or near infrared wavelengths will scatter within tissue and convert into heat. The laser can kill cancerous tissue up to 2 cm in diameter. The laser's fiber tip chars and vaporizes when trying to cover a larger area.
Dr. Lees found that by firing multiple bare fibers at 2-cm spacing, the team can treat larger tumors, but patients experience significant pain and vigorous pain control is needed after the procedure. NSAIDS can help control the intense inflammation that results.
Other techniques examined by the team include cryosurgery, ethanol ablation, and chemoembolization. The exhibit's authors believe that a combination of these techniques soon will replace most operations to remove liver tumor and open up a new field of expertise for interventional radiology.
