Imaging findings after cryoablation of breast cancer

Cryoablation has emerged as an alternative treatment for early-stage, low-risk breast cancer, particularly in patients who are not suitable candidates for surgery.

The aim of this article is to describe mammography, ultrasound, and contrast-enhanced mammography findings after successful percutaneous cryoablation (PCA) and describe signs of residual tumour or recurrence. In addition, we use our experience to propose a follow-up protocol for breast cancer patients treated with cryoablation.

We retrospectively reviewed all cases of biopsy-proven early-diagnosed breast cancer in non-surgical patients in our institution between May 2019 and December 2024. We included those cases that were treated with PCA alone, with no known distant metastases and which had at least one available follow-up image study. The following radiological studies were carried out every six months: mammography and ultrasound until November 2023 and contrast-enhanced mammography thereafter. Benign and suspicious imaging findings were assessed.

From May 2019 to December 2024, 85 malignant breast tumours were treated with PCA in our institution. Of these, 63 cases met the inclusion criteria. Mammographic studies after PCA revealed findings consistent with fat necrosis which persisted or reduced in size during follow-up. Contrast administration helped exclude malignancy, especially in cases in which the findings did not change over time in conventional imaging or in those which were high in density or had spiculated margins. The appearance of a dense mass or mass-like enhancement at the periphery of the treated area suggested malignancy.

Contrast-enhanced mammography is preferred for follow-up after PCA. Post-ablation findings-both on functional and conventional imaging techniques-are variable and it is important for radiologists to be familiar with them. We recommend performing a functional imaging study every six months for at least two years, followed by annual evaluations.