TAMPA, FL—In the first reported study, researchers in Detroit have found that image-guided, multiprobe cryo therapy may be able to successfully freeze breast cancer in women who do not undergo surgery. They presented data that show this approach appears to be highly effective with minimal discomfort for the patient.

Researchers conducted 13 cryotherapy sessions in which they treated 25 breast cancer foci in 13 patients. What makes this series unique is that it used multiple 2.4-mm cryoprobes. Using only local anesthesia with mild sedation, ultrasound guidance alone was used in six of the patients; seven patients required both computed tomography (CT) and ultrasound to better define ice margins. The researchers used saline injections to protect the skin and/or chest wall. Breast magnetic resonance (MR) imaging and/or clinical follow-up were available for up to 65 months after cryotherapy. The researchers found no significant complications. All the patients reported minimal discomfort and satisfaction with the cosmetic results. The investigators found that biopsies at the margins of the cryotherapy sites immediately after the procedure and at the cryotherapy sites in follow-up were all negative. No local recurrences have been noted at 18-month average follow-up.

“Minimally invasive cryotherapy opens the door for a potential new treatment for breast cancer and needs to be further tested. When used for local control and/or potential cure of breast cancer, it provided safe and effective breast conservation with minimal discomfort for a group of women who refused invasive surgery or had a local recurrence and needed additional management,” said study investigator Peter Littrup, MD, who is an interventional radiologist at Karmanos Cancer Institute, Detroit, Michigan. “This is the first reported study of successfully freezing breast cancer without having to undergo surgery afterward to prove that it was completely treated.”

With this cryotherapy treatment, researchers used several needle-like cryo - probes that were evenly spaced and then inserted through the skin to deliver extremely cold gas directly to the tumor to freeze it. This technique has been used for many years by surgeons in the operating room. However, in the past few years the needles have become small enough to be used by interventional radiologists through a small nick in the skin, without the need for an operation.
The “ice ball” that is created around the needle grows in size and destroys the frozen tumor cells. The major benefits of cryotherapy are its superb visualization of the ice treatment zone during the procedure. It also provides a low pain profile in an outpatient setting and has been shown to have excellent healing with minimal scarring, according to Littrup, who is also a professor of radiology, urology, and radiation oncology at Wayne State University.

He said this approach is very attractive because of the dramatic improvements in imaging that have occurred over the past 2 years. Breast imaging has markedly advanced through accurate improvements in breast MR imaging. This has paved the way for excellent treatment planning, because of clear determination of tumor size and extent within the breast. It also allows the clinician to see zones of destruction thoroughly covering the tumor after cryotherapy.

Littrup said this current study confirmed sufficiently deadly temperatures when using two or more cryo probes. Prior breast cryotherapy studies had “inexplicably” used only a single cryo probe and suggested that tumors larger than 1.5 cm could not be adequately treated.

“This is incongruent with more than 10 years of treating an entire prostate, which is approximately 5 cm, with more than six probes in order to generate well-defined sufficiently deadly temperatures throughout the whole gland. We simply translated this concept to breast cancer to assure deadly temperatures well beyond all apparent tumor margins in order to generate successful use of cryotherapy in women,” said Littrup.

He said more studies are now needed with larger numbers of breast cancer patients at multiple centers. Littrup said cryotechnology is now offering the promise of being more MR-compatible. This may allow for more accurate targeting of more difficult-to-see breast tumors. “With recent developments of powerful new cryotechnology, multiple directions for breast cryotherapy can be pursued, including translating the current, somewhat challenging procedure done with ultrasound and/or CT guidance to a more consistent and reproducible MRguided approach,” said Littrup.

He noted this may turn out to be a cost-effective approach for some women presenting with breast cancer. Littrup said oncologists can now counsel their patients that this new approach may become much more widely available in the not too distant future.

“In the future, I think there could be a broad utilization,” said Littrup in an interview with the Journal of Multidisciplinary Cancer Care. “Patients who have very few other options may be candidates.”