PT - JOURNAL ARTICLE AU - Zhaoqi Zhang AU - Xinming Zhao AU - Cuimin Ding AU - Jianfang Wang AU - Jingmian Zhang AU - Fan Wang TI - 99mTc-3PRGD2 imaging to monitor early response to EGFR- targeted therapy in lung adenocarcinoma Corresponding author: Xinming Zhao Department of Nuclear Medicine, The Fourth Hospital of Hebei Medical University, No.12 Jiangkang Road, Shijiazhuang 050011, China. E-mail: xinm_zhao@163.com DP - 2016 May 01 TA - Journal of Nuclear Medicine PG - 1420--1420 VI - 57 IP - supplement 2 4099 - http://jnm.snmjournals.org/content/57/supplement_2/1420.short 4100 - http://jnm.snmjournals.org/content/57/supplement_2/1420.full SO - J Nucl Med2016 May 01; 57 AB - 1420Objectives 99mTc-3PRGD2 is a new SPECT tracer targeting integrin αvβ3 receptor for tumor detection, angiogenesis imaging, and therapeutic efficiency evaluation. The aim of this prospective study was to assess the efficacy of 99mTc-3PRGD2 imaging in early evaluating treatment response of lung adenocarcinoma to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) therapy, so that unnecessary toxicity and costs of ineffective treatment can be avoided.Methods Seventeen lung adenocarcinoma patients with EGFR exons 18, 19, 20, or 21 mutations and planned for EGFR-TKI targeted therapy were included in this study. 99mTc-3PRGD2 SPECT/CT and planar scans were performed before (2 days) and after EGFR-TKI therapy (42.59±5.06 days). 17 patients were treated with EGFR-TKI (Icotinib 13 cases, Erlotinib 3 cases,Gefitinib 1 case). The tumor to non-tumor (T/NT) ratio on SPECT/CT and planar images were calculated. The Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 was used as standard for the evaluation of treatment response on CT images. Receiver operator characteristic (ROC) analysis was used to analyze the power to identify PR group using change in T/NT ratio on SPECT/CT and planar images.Results None of 17 patients were complete response (CR), 9 of 17 (52.94%) patients were partial response (PR), and 6 (35.29%) patients were stable disease (SD), while the other 2 (11.77%) patients were progressive disease (PD). All lung target lesions had significant 99mTc-3PRGD2 uptake at baseline. After treatment, the change in T/NT ratio on SPECT/CT and planar imaging in PR patients were 35.13% and 15.17%, SD patients were 4.34% and -3.31%, while PD patients were -76.09% and -18.71%, respectively. The change in T/NT ratio on SPECT/CT imaging in PR and PD, PR and SD, SD and PD groups had significant difference (t=7.574, 2.734 and 4.128, P<0.001, 0.017 and 0.005, respectively). On SPECT planar imaging, the difference of PR and PD group had significant difference (t= 4.533, P= 0.001), while in PR and SD, SD and PD group, there were no significant difference (t=2.261 and 1.110, P=0.059 and 0.310, respectively). From ROC analysis, the optimal cut-off point of change in T/NT ratio on SPECT/CT and planar imaging after EGFR-TKI therapy for identifying PR groups were 21.15% and 11.47% respectively.Conclusions This study primarily demonstrated that 99mTc-3PRGD2 SPECT/CT and planar imaging is a good tool for early evaluating the EGFR-targeted therapy response of lung adenocarcinoma patients. Fund:This study was supported by the Science and Technology Department of Hebei Province, China (no.15277776D).