Cryoablation can produce long-term, significant pain relief for patients who have cancer that has metastasized to bone, according to a presentation at the annual meeting of the Radiological Society of North America.

"Cancer patients are living longer and we need to be able to manage their pain over a long period of time," says Matthew Callstrom, MD, PhD, a radiologist at Mayo Clinic, who presented the talk.

Each year in the United States approximately 100,000 people have cancer that metastasizes to bone.

In the current study, cryoablation was used to treat 34 patients who had metastatic bone lesions. All patients had failed with conventional pain management treatments or refused such treatments. Eighty percent experienced a clinically significant reduction in pain after their procedure. Furthermore, the treatment appears to have lasting effects: At 24 weeks after the procedure, patients still reported significantly lower levels of pain.

"Two key parts of this study are that the reduction in pain lasts and their quality of life improves after receiving the treatment," Callstrom said.

These results are important for two reasons: First, cryoablation worked after other treatments failed to provide adequate pain relief; second, cryoablation provided long-term pain relief. Radiation therapy, which is considered the gold standard in pain management for patients with focal pain associated with metastatic cancer, provides only short-term relief for many patients, according to Callstrom.

Callstrom recently received a $900,000 grant from the National Cancer Institute to lead a nationwide prospective, randomized study to compare cryoablation and radiation therapy as treatment for pain associated with metastatic cancer.

Patients in the current study had primary cancers that included colorectal, renal cell, bronchogenic, squamous cell, adrenal cortical, ovarian and thyroid carcinomas, paragangliomas, melanoma and desmoid tumors.