{"title":"Initial Findings on the Use of [<sup>225</sup>Ac]Ac-DOTATATE Therapy as a Theranostic Application in Patients with Neuroendocrine Tumors.","authors":"Emre Demirci, Nalan Alan Selçuk, Gamze Beydağı, Meltem Ocak, Türkay Toklu, Kaan Akçay, Levent Kabasakal","doi":"10.4274/mirt.galenos.2023.38258","DOIUrl":null,"url":null,"abstract":"<p><strong>Objectives: </strong>This study aimed to evaluate the stability, safety, and efficacy of alpha-targeted therapy with [<sup>225</sup>Ac]Ac-DOTATATE in patients with grade 1/2 metastatic neuroendocrine tumors (NETs).</p><p><strong>Methods: </strong>This retrospective cohort included patients (n=11) with metastatic NETs from different primary sites (bronchial, pancreatic, nonpancreatic gastroenteropancreatic NETs, paraganglioma, and unknown primary site) treated with [<sup>225</sup>Ac]Ac-DOTATATE with a mean activity of 8.2±0.6 MBq (range: 7.5-10.0 MBq) at our institution between November 2019 and March 2022. The <i>in vivo</i> and <i>in vitro</i> stability of [<sup>225</sup>Ac]Ac-DOTATATE was calculated. The safety profile was evaluated according to the CTCAE-v5.0. Treatment efficacy was evaluated according to [<sup>68</sup>Ga] Ga-DOTATATE positron emission tomography/computed tomography (PET/CT) images and the RECIST 1.1 criteria.</p><p><strong>Results: </strong>Patients had 73% (n=8) lymph node metastases, 91% (n=10) liver metastases, 36% (n=4) lung metastases, and 73% (n=8) bone metastases. All but one patient was refractory to treatment with [<sup>177</sup>Lu]Lu-DOTATATE. [<sup>225</sup>Ac]Ac-DOTATATE was stable for at least 5 h in vitro (in saline) and 3 h <i>in vivo</i> (urine and blood samples). Grade 2 renal toxicity and grade 2 hematotoxicity were observed in one patient. No grade 3-4 toxicities were reported. According to post-treatment [<sup>68</sup>Ga]Ga-DOTATATE PET/CT (n=9), 11% (n=1) had progressive disease, 44.4% (n=4) had stable disease, and 44.4% (n=4) had a partial response. The disease control rate was 89% (n=8). The median progression-free survival estimated according to Kaplan-Meier analysis was 12 months.</p><p><strong>Conclusion: </strong>The preliminary results of this study suggest that [<sup>225</sup>Ac]Ac-DOTATATE is stable, safe, and effective for treating advanced and [<sup>177</sup>Lu] Lu-DOTATATE-refractory NETs. However, prospective studies are needed to determine the impact of treatment on overall survival and to uncover potential side effects.</p>","PeriodicalId":44681,"journal":{"name":"Molecular Imaging and Radionuclide Therapy","volume":null,"pages":null},"PeriodicalIF":0.9000,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/fe/5c/MIRT-32-226.PMC10600558.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular Imaging and Radionuclide Therapy","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.4274/mirt.galenos.2023.38258","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING","Score":null,"Total":0}
引用次数: 0
Abstract
Objectives: This study aimed to evaluate the stability, safety, and efficacy of alpha-targeted therapy with [225Ac]Ac-DOTATATE in patients with grade 1/2 metastatic neuroendocrine tumors (NETs).
Methods: This retrospective cohort included patients (n=11) with metastatic NETs from different primary sites (bronchial, pancreatic, nonpancreatic gastroenteropancreatic NETs, paraganglioma, and unknown primary site) treated with [225Ac]Ac-DOTATATE with a mean activity of 8.2±0.6 MBq (range: 7.5-10.0 MBq) at our institution between November 2019 and March 2022. The in vivo and in vitro stability of [225Ac]Ac-DOTATATE was calculated. The safety profile was evaluated according to the CTCAE-v5.0. Treatment efficacy was evaluated according to [68Ga] Ga-DOTATATE positron emission tomography/computed tomography (PET/CT) images and the RECIST 1.1 criteria.
Results: Patients had 73% (n=8) lymph node metastases, 91% (n=10) liver metastases, 36% (n=4) lung metastases, and 73% (n=8) bone metastases. All but one patient was refractory to treatment with [177Lu]Lu-DOTATATE. [225Ac]Ac-DOTATATE was stable for at least 5 h in vitro (in saline) and 3 h in vivo (urine and blood samples). Grade 2 renal toxicity and grade 2 hematotoxicity were observed in one patient. No grade 3-4 toxicities were reported. According to post-treatment [68Ga]Ga-DOTATATE PET/CT (n=9), 11% (n=1) had progressive disease, 44.4% (n=4) had stable disease, and 44.4% (n=4) had a partial response. The disease control rate was 89% (n=8). The median progression-free survival estimated according to Kaplan-Meier analysis was 12 months.
Conclusion: The preliminary results of this study suggest that [225Ac]Ac-DOTATATE is stable, safe, and effective for treating advanced and [177Lu] Lu-DOTATATE-refractory NETs. However, prospective studies are needed to determine the impact of treatment on overall survival and to uncover potential side effects.
期刊介绍:
Molecular Imaging and Radionuclide Therapy (Mol Imaging Radionucl Ther, MIRT) is publishes original research articles, invited reviews, editorials, short communications, letters, consensus statements, guidelines and case reports with a literature review on the topic, in the field of molecular imaging, multimodality imaging, nuclear medicine, radionuclide therapy, radiopharmacy, medical physics, dosimetry and radiobiology.