March 16, 2010 -- Breast cancer patients may one day be able to opt for a simple outpatient procedure to freeze their tumors as an alternative to surgery.
In a small but promising study, researchers were able to kill breast cancer cells by freezing them using a technique known as image-guided, multiprobe cryotherapy.
All 13 of the women who had the procedure were alive with no clinical evidence of cancer recurrence an average of 18 months, and up to five years, after having the procedure.
Their tumors ranged in size from very small to very large.
The study was presented at the Society of Interventional Radiology's 35th Annual Scientific Meeting in Tampa, Fla.
Peter J. Littrup, MD, who pioneered cryotherapy close to two decades ago, says the findings show that even large breast tumors can be successfully treated with the nonsurgical freezing technique.
Littrup directs imaging research and image-guided therapy at Detroit's Barbara Ann Karmanos Cancer.
How Cryotherapy Works
The cancer-killing freeze is achieved by delivering a very low temperature gas to the tumor using needle-like probes.
Littrup tells WebMD that a single-probe freezing approach has been used for several years to treat breast cancer, but it is widely considered to be unsuitable for tumors larger than 1.5 centimeters.
"We've been using multiple probes for many years to treat prostate cancer with a minimum of five probes," he says. "So it just made sense to me to try multiple probes for breast cancer."
He adds that recent technological advances resulting in smaller and easier-to-manage probes and better ways to guide them to the tumor have made nonsurgical cryotherapy an attractive option for breast cancer.
The 13 patients included in the study had a total of 25 tumors, ranging in size from 0.5 centimeters to 5.8 centimeters. The average tumor size was 1.7 centimeters.
Using local anesthesia with mild sedation, an average of three probes per tumor were guided to the tumor site using either ultrasound alone or ultrasound with computed tomography (CT) imaging. The probes produced "ice balls" ranging in size from 2 centimeters to 10 centimeters, depending on the size of the targeted tumor.
Patients reported minimal pain and a high satisfaction with the cosmetic results following the treatment.
Littrup says most patients had complete healing of the frozen area with very little or no scaring within six months.
He hopes to conduct larger studies in breast cancer patients using a cryotechnology procedure that uses magnetic resonance (MR) to guide the probes. Littrup developed and has patented this technology, and he says it is potentially useful in the treatment of many types of cancer.
Cure Rates Still Unknown
Radiologist Gale A. Sisney, MD, considers cryotherapy a very promising approach for the treatment of breast cancer that could prove to be as effective as surgical treatment.
Sisney is chief of breast imaging at the University of Wisconsin, Madison.
"We won't be able to say for some time how this compares with lumpectomy in terms of cure rates," she says.
American Cancer Society Deputy Chief Medical Officer Len Lichtenfeld, MD, says much larger studies are needed with longer follow-up to determine cryotherapy's role in the treatment of breast cancer.
"I would be cautious about any suggestion that this treatment is appropriate for a woman with cancer that is localized to the breast and possibly regional lymph nodes," he says. "Sometimes techniques like this one, which have a lot of appeal to patients, gain a following before the research is in. I would not make assumptions based on this small study."