Cryoablation For Breast Cancer: Efficacy and Techniques

Yolanda Bryce, MD, discusses the use of cryoablation for patients with breast cancer, a topic she presented on at the 2024 Symposium of Clinical Interventional Oncology.

Dr Bryce discusses the efficacy data that exists for this procedure, as well as some key points of her technique.

Transcript:

Hi, I'm Yolanda Bryce, I'm here at CIO, so fortunate to be here. I am an assistant attending at Memorial Sloan Kettering Cancer Center where I have developed a breast cryoablation program.

For my talk on breast ablation, I will be covering both cryoablation of fibroadenoma as well as breast cancer. I deal a little bit with fibroadenoma, not too much, because that has been something that is very established. And because I work at a cancer center, I don't do too many fibroadenoma, although I do sometimes.

I will concentrate, however, on the practice of breast cryoablation for cancer specifically.  And with that there is some landmark trials that have happened and some ongoing trials that are very important that have really shown the growth in this field and the promise of this field. For one the ACOSOG Z1072 trial. This was a landmark trial, our first trial that really showed the benefit of of cryoablation and breast cancer. It was 87 breast cancers that were cryoablated, went on to surgery, and that trial showed that if the patient had a small tumor —1 cm or less, it was a study that was performed with a single probe— that showed that 100% of that tumor died. And then there were other studies, much smaller, that showed, like for example, the Littrup trial that showed even if cancers were almost 6 cm, if you use multiple probes, the efficacy was still there.

That made me think about doing this procedure in the setting that I serve and where it's patients with smaller tumors, but a lot of patients that have larger tumors because it's in a poor surgical candidacy population largely. And so it got me thinking of how I can serve this population. I do use multiple probes to be able to cover the extent of the lesion. And that has given me a lot of success.

In my talk, I show my data where I have done 60 patients that is going to be published soon. And when I did these patients, a lot of these patients had larger tumors, they had multicentric, multifocal disease. And its patients included in this cohort that even when, if they had been surgical candidates, they would have been offered a mastectomy, even if I did this procedure in this population that I serve, the recurrence rate was about 10%, which is really good if you consider the other modalities that are offered to these patients that are not surgical candidates, which includes endocrine therapy and radiation where the local control is not as good. Knowing my data, knowing the other data around, knowing that there are the final results for the ICE3 trial has just come up that has shown in patients that have smaller tumors, 1.5 cm or less with low-risk biology, the recurrence rate is also very low in that population. I think 96.3% were disease free at 5 years, which is amazing.

And so with all this wealth of data, I talk about in my presentation my technique, which is, as needed, a multi-probe approach. I have a mantra that I live by, and that is every centimeter of tumor deserves a probe. So with that in mind, if tumors are 1.5 or greater, I use 2 probes, I dissect the lesion so that I'm covering the extent, and that's how I do my procedure.

A lot of these tumors, especially when they're larger or they're close to the skin, hydrodissection is key and it's something that I really preach and it's something that you really have to master to be able to be good at this technique because that ice ball will injure the skin. There's not many complications that can happen from this procedure. The biggest one is injury of the skin. For that, you really have to do great hydrodissection. If you're dealing with larger tumors or they're encroaching on the skin, hydrodissection is key.

Also, using a very close monitoring and using the active thaw mechanism on your device to be able to gain control before you start freezing again. Your goal is always to reach 10-minute freeze, then 5 to 8 minutes of passive thaw and another 10-minute freeze. And so that's your goal in trying to treat these patients, but sometimes you just cannot get to that 10-minute freeze because of the proximity to the skin. You just do the best you can, maintaining the safety of the patient.

For follow-up, after the procedure, I do a 1 month follow-up clinic visit, just to check on the patient, see how they're doing, make sure that they're happy with how their breast is looking, any complications, any questions. Usually it's just more of a question period. And then afterwards at 3 months, that's when I do my initial imaging. I find the ablative zone is much more developed at that time. I do mammogram and ultrasound at the minimum. I do some kind of contrast study and MRI or a contrast-enhanced mammogram and then at that point I decide if I want to follow them again in 6 months and then annually.

I do follow these patients indefinitely; they are my patients, I follow them, if another cancer comes up I can re-treat them or refer them. I do do referrals for all my patients to radiation oncology and medical oncology, some patients don't want that referral but I still offer it. Because in my mind, I'm thinking about this like a lumpectomy and with lumpectomies it has already been shown that with these adjuvant therapies the patients do much better with a lower recurrence rate so that's how I think about it although the data is not there yet but I'm sure soon it will be.