TY - JOUR T1 - VPAC1 Receptors for Imaging Breast Cancer: A Feasibility Study JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1019 LP - 1025 DO - 10.2967/jnumed.112.114876 VL - 54 IS - 7 AU - Mathew L. Thakur AU - Kaijun Zhang AU - Adam Berger AU - Barbara Cavanaugh AU - Sung Kim AU - Chaitra Channappa AU - Andrea J. Frangos AU - Eric Wickstrom AU - Charles M. Intenzo Y1 - 2013/07/01 UR - http://jnm.snmjournals.org/content/54/7/1019.abstract N2 - VPAC1 encodes G-protein–coupled receptors expressed on all breast cancer (BC) cells at the onset of the disease, but not on benign lesions. Our extensive preclinical studies have shown that 64Cu-TP3805 has a high affinity for VPAC1, is stable in vivo, and has the ability to distinguish spontaneously grown malignant BC masses from benign lesions. Our long-term goal is to develop 64Cu-TP3805 as an agent to perform in vivo histology, to distinguish malignant lesions from benign masses noninvasively and thereby avoid patient morbidity and the excess economic costs of benign biopsies. Methods: 18F-FDG obtained commercially served as a control. 64Cu-TP3805 was prepared using a sterile kit containing 20 μg of TP3805. Radiochemical purity and sterility were examined. Nineteen consenting women with histologically proven BC were given 370 MBq of 18F-FDG. One hour later, 6 of these patients were imaged with PET/CT and 13 with positron emission mammography (PEM). Two to 7 d later, 6 PET/CT patients received 111 MBq (±10%) (n = 2), 127 MBq (±10%) (n = 2), or 148 MBq (±10%) (n = 2) of 64Cu-TP3805 and were imaged 2 and 4 h later. Thirteen PEM patients received 148 MBq (±10%) of 64Cu-TP3805 and were imaged 15 min, 1 h, 2 h, and 4 h later. Standardized uptake value (SUV) was calculated for PET/CT patients, and PUV/BGV (PEM uptake value/background value) was calculated for PEM patients. Tumor volume was also calculated. Results: The radiochemical purity of 64Cu-TP3805 was 97% ± 2%, and specific activity was 44.4 GBq (1.2 Ci)/μmol. In 19 patients, a total of 24 lesions were imaged (15 invasive ductal carcinoma, 1 high-grade mammary carcinoma, 3 lobular carcinoma, 1 invasive papilloma, and 4 sentinel lymph nodes). All lesions were unequivocally detected by 64Cu-TP3805 and by 18F-FDG. The average tumor volume as determined by PET/CT with 64Cu-TP3805 was 90.6% ± 16.1% of that with 18F-FDG PET/CT, and the average SUV was 92% ± 26.4% of that with 18F-FDG. For PEM, the tumor volume with 64Cu-TP3805 was 113% ± 37% of that with 18F-FDG and the PUV/BGV ratio was 97.7% ± 24.5% of that with 18F-FDG. Conclusion: 64Cu-TP3805 is worthy of further investigation in patients requiring biopsy of suggestive imaging findings, to further evaluate its ability to distinguish malignant lesions from benign masses noninvasively. ER -