Abstract Introduction: The diagnostic performance of the first European PEM (PET mammography) is based on individualized dosage of FDG evaluated in 108 females with 166 suspected breast lesions. Methods: PEM imaging of the breast was performed in 108 consecutive females with 166 suspicious breast lesions or known breast cancer (BC) 90 min after i.v. application of 3.5 MBq/kg F-18-FDG per kg body weight. The maximum PEM uptake value (PUV) was derived from a ROI around the target lesion and was correlated with a corresponding non-target ROI in the contra lateral healthy breast to determine the target/non-target ratio (PUV-ratio). Images were analyzed by 2 experienced readers independently as compared to histopathology in all cases. The between group analyses for all malignant, benign and corresponding non-target lesions were calculated by paired Student t-Test. The mean target/non-target ratio in patients with BC compared to healthy patients was calculated by independent Student t-Test. Significance level was considered at p value <0.05. Receiver operating characteristic (ROC) analyses were employed to determine associations with PUV and PUV-ratio. Results: A total of 27 out of 166 (16.2%) lesions were malignant. Mean of PUV was estimated to be 3.9±2.5 in malignant lesions and 1.2±0.4 for the contra-lateral healthy breast (p<0.001). The mean PUV-ratio in patients with BC of 3.4±1.5 was significantly higher as compared to benign lesions 1.2±0.3 (p<0.001). The area under the ROC curve was 0.997 (0.000-1.000) for PUV and 0.986 (0.965-1.000) for PUV-ratio. PEM was true-positive in 27 cases of cancers and false positive in 3 cases (papilloma, mastopathia bds.) considering a PUVmax > 1,9, resulting in sensitivity of 100%, specificity of 97%, positive predictive value of 90%, and a negative predictive value of 100%. Conclusion: The different European approach in PEM using personalized FDG-dosage enables the comparability of FDG-metabolism in patients, resulting in a high diagnostic accuracy of PEM tests. Literature: 1. Hentschel M. et al. Can body volume be determined by PET? Eur J Nucl Med Mol Imaging 32:564–568 (2005) 2. Berg W., et al. Comparative Effectiveness of PEM and MRI for Presurgical Planning of the Ipsilateral Breast in Women with Breast Cancer. Radiology 1:258 (2011) 3. Narayanan D, Madsen KS, Kalinyak JE, Berg WA. Am J Roentgenol. 196:971-81(2011) 4. Kalinyak, JE et al, PET guided breast biopsy. Breast J. 17:143-151(2011) 5. Caldarella C. et al., Diagnostic Performance of Dedicated Positron Emission Mammography Using Fluorine-18- Fluorodeoxyglucose in Women With Suspicious Breast Lesions: A Meta-analysis. Clinical Breast Cancer: in Press. Citation Format: Frank HH Müller, Hentschel Michael, Anton G Müller, Jamshid Farahati. PEM tests will have a high accuracy detecting breast cancer, if an individualized dosage of F-18-FDG is used [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-01-11.