Assessment of tumor response to antiangiogenic chemotherapy for hepatic breast cancer metastases: Imaging of the malignant neoangiogenesis with perfusion ct vs. contrast-enhanced ultrasound (CEUS)

Objectives: Malignant angiogenesis affects tumor growth, local expansion and metastasis. Antiangiogenic chemotherapies act to reduce tumoral cell growth acting as angiogenesis inhibitor for endothelial cells. Objective tumor response is a common endpoint to evaluate the efficacy of anticancer agents. World Health Organization (WHO) or Response Evaluation Criteria in Solid Tumors Group (RECIST) criteria are not appropriate for the evaluation of targeted therapy because tumoral hypoxia is independent from tumor volume. The purpose of this study was to evaluate whether CEUS could be used to evaluate tumor response to antiangiogenic therapy in Patients with hepatic breast cancer metastases.

Methods: 15 Patients with advanced breast cancers with hepatic localization were evaluated for morphological and functional parameters with CEUS and perfusion CT. Both CEUS and perfusion CT examinations were obtained at baseline and after 1 and 3 months on antiangiogenic therapy. The sum of the maximum diameters of individual hepatic target lesions and the tumoral vascular index (percentage of contrast uptake) were assessed with CEUS and perfusion CT.

Results: CEUS showed a reduction of tumor vascularization before a reduction in tumor size in all cases. CEUS accurately measured the size of the lesions and allowed the detection of microvascularization to confirm the absence of residual neovessels.

Conclusions: CEUS is an effective tool for evaluating the biological response to chemotherapy of metastatic breast cancer as it allows both an eccellent evaluation of the lesion size, in particular for small metastasis in steatosic livers and a good assessment of vascular patterns of the lesions.