New Microwave Technology Can Be Safely Applied To Cancerous Lung Tumors, Study Suggests

Similar to radiofrequency ablation, microwave ablation is a minimally invasive, image-guided technique that uses heat generated by microwave energy to destroy tumors. Rhode Island Hospital physicians became the first in the United States to use microwave ablation to treat cancer and are one of only ten facilities in the country that offer the treatment.

In the study, Damian Dupuy, M.D., director of tumor ablation at Rhode Island Hospital, and radiologists treated 50 patients with microwave ablation 66 times for 82 lung tissue masses. Each tumor was ablated under computed tomography (CT)-guidance for seven to ten minutes and patients were followed up at one, three and six months with CT and positron emission tomography (PET) imaging.

All 50 patients had technical completion of their ablation. Patients with the largest tumors – or 26 percent of the overall study population – were found to have residual disease at the ablation site. An additional 22 percent of patients had recurrent disease. Yet an analysis of cancer-specific mortality yielded a one-year survival of about 83 percent, two-year-survival of approximately 73 percent, and a three year survival of about 61 percent – regardless of tumor size or the presence of residual disease.

“Microwave ablation offers patients with inoperable lung cancer or those who cannot benefit from more traditional therapies with a much-needed minimally invasive treatment option,” said Dupuy, who’s also a professor of diagnostic imaging at The Warren Alpert Medical School of Brown University and a national expert on microwave ablation. “Our findings are very promising, but because this technology is still relatively new, it’s important that we continue to examine its safety and efficacy in providing patient care.”

During microwave ablation, radiologists use imaging guidance to place a thin microwave antenna directly into the tumor. A microwave generator emits an electromagnetic wave that agitates water molecules in the surrounding tumor tissue, producing friction and heat that eventually destroy the tumor.

Co-authors included David J. Grand, M.D., Thomas DiPetrillo. M.D., and William Mayo-Smith, M.D, all of Rhode Island Hospital and Alpert Medical School; Jason Machan, Ph.D., research statistician at Rhode Island Hospital; and Farrah J. Wolf, a medical student at Alpert Medical School. (Abstract VI51-10)