Percutaneous Cryoablation for the Treatment of Breast Cancer

Overview

The goal of this clinical trial is to study cryoablation as a treatment for selected adults with localized breast cancer. Cryoablation uses very low temperatures to destroy the tumor through thin needles placed through the skin under ultrasound guidance. The main questions this study aims to answer are: * Can cryoablation completely destroy the treated breast tumor? * Is the procedure safe and well tolerated? * Can ultrasound and contrast-enhanced mammography be used to monitor the treated area after cryoablation? The study will include participants with breast cancer who cannot undergo surgery or choose not to have surgery, as well as selected postmenopausal participants with small, low-risk breast cancers. Participants will undergo ultrasound-guided cryoablation instead of surgical removal of the breast tumor. They will then have clinical examinations and imaging follow-up, including ultrasound and contrast-enhanced mammography, to assess the treated area over time. A biopsy will be performed if follow-up findings are suspicious or unclear. Other cancer treatments, such as radiation therapy or hormone therapy, will be given when indicated according to standard clinical practice.

CRYSTAL is a prospective, single-center, single-arm interventional study evaluating ultrasound-guided percutaneous cryoablation for the treatment of selected patients with localized breast cancer. The study includes two clinical cohorts. Cohort A includes patients with localized breast cancer who are not suitable candidates for surgery because of age, comorbidities, or other clinical factors, as well as patients who decline surgery after appropriate multidisciplinary evaluation and counseling. Cohort B includes selected postmenopausal patients with small, unifocal, biologically low-risk breast cancers considered suitable for a minimally invasive treatment strategy. All participants will have histologically confirmed breast cancer before treatment, with assessment of relevant prognostic and predictive tumor markers. Eligibility and treatment strategy will be discussed within the multidisciplinary breast unit. Cryoablation will be performed percutaneously under ultrasound guidance. The procedure will aim to obtain complete coverage of the tumor by the ice ball with an appropriate safety margin while protecting the skin, chest wall, and other adjacent structures. Participants will undergo clinical and imaging surveillance after treatment. Ultrasound and contrast-enhanced mammography (CEM) will be the principal imaging techniques used to assess the ablation area and detect possible residual or recurrent disease. Breast magnetic resonance imaging may be used when CEM is contraindicated, not feasible, or inconclusive. Tissue sampling will be performed when clinical or imaging findings are suspicious or inconclusive. The primary objective is to evaluate complete local tumor ablation approximately 6 months after cryoablation. Secondary objectives include technical success, procedure-related adverse events, residual disease, need for repeat cryoablation or subsequent surgery, procedural characteristics, quality of life, and local recurrence during follow-up. Adjuvant systemic treatment and/or radiation therapy will be administered when clinically indicated according to multidisciplinary assessment and standard clinical practice. Participants will be followed for up to 24 months after cryoablation.