A new noninvasive approach in breast cancer therapy using magnetic resonance imaging-guided focused ultrasound surgery

An ideal vision of modern medicine includes tumor surgery with the human bo dy remaining completely intact. A noninvasive therapy could avoid infection s and scar formation;, it would require less anesthesia, reduce recovery ti me, and possibly also reduce costs. This study investigated whether human b reast cancer can be effectively treated with a novel combination of image g uidance and energy delivery, noninvasive magnetic resonance imaging (MRI)-g uided focused ultrasound (FUS). We have developed a FUS therapy unit guided by MRI for the treatment of human breast tumors in a clinical 1.5 T MR sca nner. With interactive target segmentation on MRI, defined volumes could be noninvasively treated in a single session with on-line NIR temperature con trol. The ultrasound waves were focused through the intact skin and resulte d in the localized thermal tissue ablation at a maximum temperature of 70 d egreesC. The therapy principle was first demonstrated in sheep breast in vi vo and was then applied in a patient with core biopsy-proven invasive breas t cancer 5 days before breast-conserving surgery. MRI proved suitable to de lineate the breast cancer, served as stereotactic treatment planning platfo rm, and delineated the FUS-related tissue changes such as interruption of t umor blood flow. Furthermore, MRI localized the hot spot in the tumor and m easured temperature elevation during the treatment. This allowed us to moni tor the efficacy and safety of FUS therapy. Immunohistochemistry of the res ected specimen demonstrated that FUS homogeneously induced lethal and suble thal tumor damage with consecutive up-regulation of p53 and loss of prolife rative activity. This effect was realized without anesthesia and damage to the surrounding healthy tissue or systemic effects. Overall, our results sh ow that noninvasive MRI-guided therapy of breast cancer is feasible and eff ective. Thus, MRI-guided FUS may represent a new strategy for the neoadjuva nt, adjuvant, or palliative treatment in selected breast cancer patients an d in patients with other soft-tissue tumors.