The study included 21 patients whose tumors in the abdomen, liver, lung and bone could not be removed surgically. Cryoablation was used to treat 48 tumors, killing 47 of them (98%). From the time of diagnosis of metastatic disease, average patient survival time was more than four years and seven months. That is significant because women whose tumors are not successfully removed surgically―which occur in about 60% of cases, according to studies―typically survive from about seven months to two and a half years. On average, more than three years had transpired from the time of diagnosis to the first cryoablation treatment, meaning these women had already passed their expected survival time, and yet cryoablation was able to extend their survival even further. Some patients had multiple cryoablation treatments and of 41 procedures, there were three major complications (7%). The complications included two deaths that were attributed to the cancer, not to the procedure.
The study also determined the treatment was extremely cost-effective, costing an average of US$26,806 per life year saved, well below the current standard of US$100,000.
“This study adds to the evidence that cryoablation is an effective option for patients who cannot have surgery,” said study author Hyun J Bang, a radiologist resident at Wayne State University/Detroit Medical Center, USA. “This procedure is often overlooked, but based on the high survival rate, cost effectiveness, consistent local control and safety of the procedure; we should be taking a closer look at cryoablation as an option before these women enter the later stages of their disease.”
In cryoablation, a small needle is placed through the skin into the tumor, which is located using imaging guidance. High pressure argon flows to the tip of the cryoprobe where it expands in an internal chamber, causing a powerful cooling effect on the outside of the probe. This allows for rapid ice formation, which freezes and kills tumor cells.
