March 4, 2010 - Using cryoablation to freeze a cancer kills it in its place, and also appears to generate an immune response that helps stop the cancer's spread, leading to improved survival rates over surgery, according to a new study in mice published in Annals of Surgical Oncology.
Researchers at the University of Michigan Comprehensive Cancer Center looked at two different cryoablation techniques, which both involve applying a cold probe to a tumor to freeze it. The study was done in mice with breast cancer. One method involves freezing the tumor rapidly, in about 30 seconds; the other freezes the tumor slowly, taking a few minutes. Results from the cryoablation were compared to results from mice whose tumors were removed with surgery.
Both cryoablation techniques successfully killed the breast tumor. The mice treated with the rapid freeze had fewer tumors that spread to the lungs and improved survival compared to mice treated with surgery alone or mice treated with the slower freezing technique. The study showed that the benefit from the rapid freezing is likely due to changes in the immune system that help to kill the tumor. Freezing with the slower technique appeared to make the immune system not as able to kill the tumor.
The study appears online in Annals of Surgical Oncology. Based on these results from mice, researchers are now conducting a clinical trial using cryoablation in patients with breast cancer. In this trial, researchers use the rapid freezing technique.
Source: Annals of Surgical Oncology, DOI 10.1245/s10434-009-0846-1.
For more information: www.annsurgoncol.org