Background Breast cancer screening imaging techniques with mammography or MRI have a suboptimal sensitivity. Vascular endothelial growth factor (VEGF)-A, is overexpressed in most malignant breast tumors. Zirconium-89 (89Zr) labeled bevacizumab provides a noninvasive tool to visualize tumor VEGF-A in patients. Therefore we performed a feasibility study to determine whether this 89Zr-bevacizumab PET technique allows detection of breast cancer lesions. Methods Newly diagnosed breast cancer patients, scheduled to undergo mastectomy or lumpectomy, underwent a PET/CT scan of the upper thoracic region (including breasts and axillae) 4 days after 37 MBq/ 5mg 89Zr-bevacizumab tracer administration. 89Zr-bevacizumab uptake in breast tumor, normal glandular tissue and axillary lymph nodes (ALN), was quantified as the maximum standard uptake value (SUVmax). PET images were visually compared with standard breast imaging techniques. When sufficient tissue was available, VEGF-A levels were assessed with Enzyme-Linked Immuno Sorbent Assay (ELISA). Data are presented as mean ± standard deviation and range. Statistical analysis was performed using the paired t-Test test (SPSS, version 18.0). A double sided p-value Results Twenty-five of 26 breast tumors (size: 25.1 mm ± 19.8, range 4-80) in 23 patients were visualised. 89Zr-bevacizumab uptake was higher in breast tumors than normal breast tissue (SUVmax in breast tumors 1.8 ± 1.2, range 0.5-5.6 versus 0.59 ± 0.37, range 0.27-1.69 in ipsilateral and 0.51 ± 0.26, range 0.20-1.12 in contralateral normal breast tissue; p Conclusions 89Zr-bevacizumab uptake was shown in 96.1% of primary breast tumors. Future breast cancer studies will include fluorescent labeled bevacizumab. (ClinicalTrials.gov identifier: NCT00991978). Disclosure All authors have declared no conflicts of interest.
