RT Journal Article
SR Electronic
T1 Immuno-PET imaging and radioimmunotherapy of <sup>64</sup>Cu/<sup>177</sup>Lu labeled anti-EGFR antibody in esophageal squamous cell carcinoma
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1216
OP 1216
VO 56
IS supplement 3
A1 Song, In Ho
A1 Lee, Tae Sup
A1 Park, Jong Ho
A1 Kim, Kwang Il
A1 Lee, Yong Jin
A1 Kang, Joo Hyun
A1 Choi, Chang woon
A1 Lim, Sang Moo
YR 2015
UL http://jnm.snmjournals.org/content/56/supplement_3/1216.abstract
AB 1216 Objectives Epidermal growth factor receptor(EGFR) is a valid target for targeted therapy in several tumors.Due to high frequency of EGFR expression in esophageal squamous cell carcinoma(ESCC), it is expected to treat ESCC patient with targeted therapy with anti-EGFR antibody such as cetuximab.We evaluated for feasibility of immuno-PET and radioimmunotherapy(RIT) in ESCC model using 64Cu/177Lu-cetuximab (CET).Methods CET was conjugated with SCN-Bn-PCTA. Serum stability and immunoreactivity of 64Cu/177Lu-CET were tested.In vivo EGFR status was evaluated with Immuno-PET using 64Cu-CET in ESCC,TE-4 and TE-8 xenografts.Biodistribution of 64Cu/177Lu-CET was performed.SPECT/CT imaging and digital whole body autoradiography(DWBA) were performed in TE-8 model.Therapeutic efficacy of 177Lu-CET was evaluated and compared with cold antibody and saline in TE-8 model.Therapeutic response with FDG-PET and IHC staining was evaluated in RIT of 177Lu-CET.Results 64Cu/177Lu-CET was prepared with high radiolabeling yield and showed high stability and good immunoreactivity. Biodistribution, immuno-PET, SPECT/CT and DWBA showed specific uptake in ESCC tumor depending on EGFR expression level. Tumor peak uptake of 64Cu-/177Lu-CET was at 48 h and 120 h, respectively. 177Lu-RIT group showed good tumor growth inhibition and marked reduction of FDG SUV compared to that of other groups (p&lt;0.05). TUNEL and Ki-67 staining(%) increased and decreased, respectively, in RIT group (p&lt;0.01) compared to other groups.Conclusions 64Cu-CET immuno-PET represented EGFR expression in ESCC tumor and 177Lu-CET showed good radioimmunotherapeutic efficacy. Diagnostic and therapeutic radionuclide convergence radiopharmaceutical,64Cu/177Lu-PCTA-CET may be useful for a diagnostic tool in patient selection and a potent RIT agent in EGFR positive ESCC tumor.