Fluorodeoxyglucose positron emission tomography/computed tomography findings after percutaneous cryoablation of early breast cancer

BACKGROUND: To document (18)F-Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) findings after percutaneous cryoablation for early breast cancer. METHODS: Data of 193 consecutive patients who had undergone cryoablation for invasive ductal carcinoma or ductal carcinoma in situ ≤ 15 mm without a history of ipsilateral breast cancer, synchronous ipsilateral lesion, and with estrogen receptor positive/human epidermal growth factor 2 negative were enrolled. The imaging characteristics of the treated areas were evaluated and classified on CT images as one of two types: fatty mass or non-fatty mass type. The maximum standardized uptake value (SUVmax) of the initial post-cryoablation PET/CT, the CT type of the treated area and selected clinical factors (age, menopausal status, lesion area, breast density, timing of PET/CT) were retrospectively evaluated. RESULTS: The median interval between cryoablation and the initial post-cryoablation PET/CT was 12 months. The median SUVmax of the treated area was 1.36. The CT findings of the treated area were classified as fatty mass type (n = 137, 71.0%) or non-fatty mass type (n = 56, 29.0%). The treated areas of patients with lower breast density, of older age, post-menopausal status, and lower radiation dose were significantly more likely to be of fatty mass type (P < 0.001). Non-fatty mass type averaged a significantly higher SUVmax than did fatty mass type. CONCLUSIONS: Post-cryoablation PET/CT findings are of fatty or non-fatty mass type. A non-fatty appearance, which can show higher SUVmax, does not necessarily denote recurrence.