RESUMO
Human copper transporter 1 (hCtr1) is the main transporter of copper which has been involved as an essential cofactor in biological processes and mechanisms of action for cisplatin and its analogues. Although expression of hCtr1 is present in all tissues that require copper, several studies have showed that levels of expression are highly variable between normal and neoplastic tissues. We evaluated the potential diagnostic of the 64CuCl2-PET/CT in patients with wild type non-small cell lung cancer (NSCLC). Eleven patients were included. Baseline 18F-FDG-PET/CT and 64CuCl2-PET/CT performed before to initiate treatment with platinum-based chemotherapy. 18F-FDG-PET/CT detected a total of 68 lesions in different corporal sites: lung (24), regional lymph node (30), distant non-bone metastases (17) and bone metastases (14). Of total, 73% demonstrated high focal uptake of 64CuCl2-PET/CT: 36% in primary tumor and 27% in lymph-nodes metastases. The detection-rates (DRs) was lower with 64CuCl2 PET/CT compared to 18F-FDG-PET/CT, however, these was not statistically significant (P = 0.108). A complete match was found in 2 patients. All patients were treated with platinum-based chemotherapy. According to RECIST 1.1 and PERCIST 1.0 criteria, most patients with highest uptake 64CuCl2-PET/CT presented partial response (mean 3 cycles) corroborated with 18F-FDG PET/CT. On the other hand, patients with very low uptake or faint uptake have progressive disease (3/16 patients). To our knowledge, this is the first study with 64CuCl2-PET/CT in-human in patients with NSCLC chemo-naïve. Our results may represent that 64CuCl2-PET/CT had a good ability for detect lesions. In addition, the 64CuCl2 uptake is based on the expression of Ctr1 transporters seeking to differentiate between those patients who may benefit from platinum-based therapy. More studies are necessary for confirm these findings.