Cryoablation

Angelika Demmerschmidt spoke with Prof. Dr. med. Andreas H. Mahnken, Director of the Department of Diagnostic and Interventional Radiology at the University Hospital of Marburg.

Could you first explain the technique of cryoablation and its application in primary breast cancer?

Prof. Mahnken: Cryoablation is a minimally invasive therapy where tumors are destroyed using cold. Cells cannot survive at temperatures below approximately -20°C for a prolonged period. When tissues are repeatedly frozen and thawed, a cascade of processes is triggered, involving not only the effects of cold but also other factors, such as the movement of fluid in and out of the cell. These processes lead to tissue death. This approach can be used not only for breast cancer but also for bone cancer or other forms of cancer. Cold is delivered through very thin needles directly into the tumor, making the method applicable to any part of the body. Thus, cryotherapy is not limited to breast cancer treatment; it is also used, for example, for treating metastases in organs.

For breast cancer treatment with cryotherapy under imaging guidance (breast MRI), one or more needles, about 1.5 mm in diameter, are inserted into the tumor. Then, cycles of freezing and thawing are performed over approximately 25-30 minutes. Unlike thermal methods, the ice ball formed during freezing can be visualized very well in three dimensions using radiological imaging. This ensures that all areas of the tumor are treated, and adjustments can be made if necessary. The treatment is performed under local anesthesia.

For which patients with breast cancer, at what stage, and at what tumor size can cryotherapy be used as a therapeutic option?

Prof. Mahnken: Indications for curative, i.e., therapeutic, cryotherapy in primary breast cancer should be strictly limited. Patients should have only one tumor node, ideally <1.5 cm, with a maximum size of up to 2 cm. Larger tumors significantly reduce the effectiveness of the treatment. There should be no lymph node metastases or large components of DCIS (ductal carcinoma in situ, an early form of breast cancer confined to the milk ducts that has not yet invaded surrounding tissues).

Each case should be individually evaluated within the framework of a multidisciplinary oncology board, as cryoablation is currently an individualized approach, not included in standard guidelines.

In which cases should cryoablation not be performed, and surgery be chosen instead?

Prof. Mahnken: If the goal is complete cure, cryotherapy should not be used for tumors larger than 1.5-2 cm. Additionally, as mentioned, large components of DCIS may hinder healing. Other contraindications include tumor infiltration of the skin and tumors located directly behind the nipple.

What advantages does cryoablation offer to breast cancer patients compared to surgery, assuming proper indication selection?

Prof. Mahnken: Overall, cryotherapy is less traumatic than surgery. Cosmetic outcomes are also very favorable, as the procedure usually does not require incisions, and the needles are inserted directly through the skin.

Can complications arise during cryoablation, and how common are they?

Prof. Mahnken: The main potential complications are similar to those of vacuum-assisted biopsy: bleeding, infection, and skin damage. However, these are generally rare.

What is the current status of comparing cryoablation with surgery? Are there any data suggesting that cryoablation might be equally effective, especially regarding recurrences?

Prof. Mahnken: The first prospective study was published only in 2016, where invasive ductal carcinomas <2 cm were first treated with cryotherapy and then surgically removed within 28 days. Cryotherapy was found to be fully effective in 92% of cases. Notably, all tumors <1 cm were completely eradicated by cryotherapy.

However, a more recent study from 2023, where cryotherapy was also followed by surgery, showed worse results due to larger tumor sizes. This highlights the need for careful patient selection. While cryotherapy cannot yet be considered a first-line treatment, if the data for small tumors is confirmed, there may be changes in therapy. Currently, two multicenter studies are of particular interest — the ICE3 study (NCT02200705) and the FROST study (NCT01992250). The interim 3-year report from ICE3, published in 2021, showed a recurrence rate of 2.06%, comparable to the results of breast-conserving surgery. No data is yet available from the FROST study.

Sourse: Mamazone