Ryan D Niederkohr, Stephen P Hayden, James J Hamill, Judson P Jones, Joshua D Schaefferkoetter, Edison Chiu
{"title":"Reproducibility of FDG PET/CT image-based cancer staging and standardized uptake values with simulated reduction of injected FDG dose or acquisition time.","authors":"Ryan D Niederkohr, Stephen P Hayden, James J Hamill, Judson P Jones, Joshua D Schaefferkoetter, Edison Chiu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p><sup>18</sup>F-fluorodeoxyglucose (FDG) PET/CT is widely used for oncologic imaging. This study aimed to evaluate, using data simulation, if reduction of injected FDG dose or PET acquisition time could be technically feasible when utilizing a sensitive commercial PET/CT imaging system, without sacrificing image quality, image-based staging accuracy, or standardized uptake value (SUV) accuracy. De-identified, standard of care oncologic FDG PET/CT datasets from 83 adults with lymphoma, lung carcinoma or breast carcinoma were retrospectively analyzed. All images had been acquired using clinical standard dose and acquisition time on a single PET/CT system. The list mode datasets were retrospectively software reprocessed to achieve undersampling of counts, thus simulating the effect of shorter PET acquisition time or lower injected FDG dose. The simulated reduced-count images were reviewed and compared with full-count images to assess and compare qualitative (subjective image quality, stage stability) and semi-quantitative (image noise, SUVmax stability, signal-to-noise and contrast-to-noise ratios within index lesions driving cancer stage) parameters. While simulated reduced-count images had measurably greater noise, there appeared to be no significant loss of image-based staging accuracy nor SUVmax reproducibility down to simulated FDG dose of 0.05 mCi/kg at continuous bed motion rate of 1.1 mm/sec. This retrospective simulation study suggests that a modest reduction of either injected FDG dose or emission scan time might be feasible in this limited oncologic population scanned on a single PET/CT system. Verification of these results with prospectively acquired images using actual low injected FDG activity and/or short imaging time is recommended.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8569332/pdf/ajnmmi0011-0428.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39711881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Charles Marcus, Olayinka A Abiodun-Ojo, Ashesh B Jani, David M Schuster
{"title":"Clinical utility of <sup>18</sup>F-Fluciclovine PET/CT in recurrent prostate cancer with very low (≤0.3 ng/mL) prostate-specific antigen levels.","authors":"Charles Marcus, Olayinka A Abiodun-Ojo, Ashesh B Jani, David M Schuster","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to evaluate <sup>18</sup>F-fluciclovine PET/CT detection rates in the evaluation of biochemical recurrence in prostate cancer patients with very low (≤0.3 ng/mL) serum prostate-specific antigen (PSA) levels following definitive treatment. Prostate cancer patients with biochemical recurrence and very low serum PSA (≤0.3 ng/mL) who underwent clinical <sup>18</sup>F-fluciclovine PET/CT were included in this single-institution retrospective study. PET/CT clinical reports at the time of interpretation were reviewed and categorized as positive or negative. In patients who had further evaluation with imaging and/or biopsy, the results were recorded to determine the true detection rate. Of the 64 eligible patients with very low serum PSA (median serum PSA of 0.17 ng/mL), 57.8% (37/64) scans were categorized as positive. Stratified by PSA levels, positivity rates were 43.8% (7/16), 60.0% (15/25) and 65.2% (15/23) for PSA<0.1 ng/mL, 0.1-<0.2 ng/mL and 0.2-≤0.3 ng/mL, respectively. The most common location of disease was the prostate bed (73%), followed by pelvic lymph nodes (22%) and distant disease (14%). In the small subset of patients who had further evaluation after a positive study (n=7), all had confirmed disease with a positive predictive value of 100%. In conclusion, among prostate cancer patients with biochemical recurrence, <sup>18</sup>F-fluciclovine PET/CT is useful in patients with very low serum PSA of ≤0.3 ng/mL, with a 57.8% positivity rate, higher than previously reported. Though standard of truth could only be ascertained in 19% (7/37) of patients with a positive study, the positive predictive value was 100%.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8569337/pdf/ajnmmi0011-0406.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39711879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abass Alavi, Thomas J Werner, William Raynor, Poul Flemming Høilund-Carlsen, Mona-Elisabeth Revheim
{"title":"Critical review of PET imaging for detection and characterization of the atherosclerotic plaques with emphasis on limitations of FDG-PET compared to NaF-PET in this setting.","authors":"Abass Alavi, Thomas J Werner, William Raynor, Poul Flemming Høilund-Carlsen, Mona-Elisabeth Revheim","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Applications of various positron emission tomography (PET) tracers for assessing atherosclerosis have been evolving over the years. <sup>18</sup>F-fluorodeoxyglucose (FDG)-PET was introduced in 2001 as a probe for this purpose. During the past decade, numerous papers have described a major role for sodium <sup>18</sup>F-fluoride (NaF) as another tracer for assessing this vascular disease. We have reviewed the existing data about the merits of both techniques for assessing atherosclerosis. We have to emphasize that our team has been actively involved in conducting research with both tracers over many years. In this review, we have relied upon the data from the CAMONA study which has become a gold standard for defining the role of PET imaging in atherosclerosis. This study was one of the largest of any in recent years and has allowed comprehensive comparison between these two tracers in detecting and quantifying atherosclerosis. Based on what we have learned from this major undertaking, we believe the role of FDG-PET will be limited in assessing atherosclerosis in clinical work-up. This is relevant to both major and coronary arteries. In contrast to NaF-PET, the role of FDG-PET in assessing coronary artery atherosclerosis is almost non-existent. Based on the existing data in this domain, NaF-PET is an ideal imaging modality for both research and clinical assessment of atherosclerosis. The aim of this review is to describe the pros and cons of both approaches based on the existing data in the literature.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8569336/pdf/ajnmmi0011-0337.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39711874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura Saule, Maija Radzina, Mara Liepa, Lilita Roznere, Marika Kalnina, Andrejs Lioznovs, Edgars Mamis, Madara Mikelsone, Juergen Biederer, Egils Vjaters
{"title":"Diagnostic scope of <sup>18</sup>F-PSMA-1007 PET/CT: comparison with multiparametric MRI and bone scintigraphy for the assessment of early prostate cancer recurrence.","authors":"Laura Saule, Maija Radzina, Mara Liepa, Lilita Roznere, Marika Kalnina, Andrejs Lioznovs, Edgars Mamis, Madara Mikelsone, Juergen Biederer, Egils Vjaters","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The aim of this study was to compare the diagnostic tools-<sup>18</sup>F-PSMA-1007 positron emission tomography (PET/CT), magnetic resonance imaging (MRI) and bone scintigraphy for the evaluation of local recurrence, regional lymph nodes and bone metastases of recurrent prostate cancer (PCa). 28 PCa patients after radical prostatectomy and/or radiation therapy and with biochemical relapse were enrolled in this study. The evaluation of local recurrence and regional lymph node metastases was based on results of PET/CT and MRI. Local recurrent disease in 28 patients was detected by PET/CT in 36% (10/28) and by MRI in 32% (9/28) with sensitivity, specificity, accuracy of 90.9%, 100%, 96.4% and 81.8%, 100%, 92.9%, respectively (kappa 0.92, P<0.001). Nodal involvement was confirmed by PET/CT and MRI in 46% (13/28) and 25% (7/28) with sensitivity, specificity and accuracy for PET/CT 92.3%, 93.3%, 92.9% and for MRI-53.8%, 100%, 78.6%, respectively (kappa 0.57, P<0.001). The evaluation of skeletal metastases was based on PET/CT and bone scintigraphy. Bone metastases were seen on PET/CT and bone scintigraphy in 21% (6/28) and 20% (5/25) with sensitivity, specificity and accuracy of 100%; 91.7%; 92.9% and 50.0%; 85.7%; 80.0%, respectively (kappa 0.41, P<0.01). In conclusion, our comparative study demonstrates advantages of <sup>18</sup>F-PSMA-1007 PET/CT compared to MRI and scintigraphy for the evaluation of recurrent prostate cancer. Both methods, <sup>18</sup>F-PSMA-1007 PET/CT and MRI, detect local recurrence with high accuracy and excellent agreement, which may be attributed to the low urinary background clearance of <sup>18</sup>F-PSMA-1007.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8569331/pdf/ajnmmi0011-0395.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39711878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amin Haghighat Jahromi, Matthew Zabel, Ryosuke Okamura, Carl K Hoh, Razelle Kurzrock
{"title":"Variant allele fraction of genomic alterations in circulating tumor DNA (%ctDNA) correlates with SUV<sub>max</sub> in PET scan.","authors":"Amin Haghighat Jahromi, Matthew Zabel, Ryosuke Okamura, Carl K Hoh, Razelle Kurzrock","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The relationship between higher variant allele fraction (VAF) of genomic alterations in circulating tumor DNA (%ctDNA), an indicator of poor outcome, and maximum standardized uptake value (SUV<sub>max</sub>), the most commonly used semi-quantitative parameter in <sup>18</sup>F-FDG PET/CT, has not been studied. Overall, 433 cancer patients had blood-based next generation sequencing. Maximum and sum of %ctDNA alterations (%ctDNA<sub>max</sub> and %ctDNA<sub>sum</sub>, respectively) represent the maximum and sum of VAF, reported as a percentage. The subset of 46 eligible patients had treatment-naïve metastatic disease and PET/CT imaging, with median 13 days prior to ctDNA testing. We found a linear correlation between the maximum VAF (%ctDNA<sub>max</sub>) (as well as the sum of the VAFs (%ctDNA<sub>sum</sub>)) and SUV<sub>max</sub> of the most <sup>18</sup>F-FDG-avid lesion (r=0.43, P=0.003; r=0.43, P=0.002; respectively). Our data suggest that SUV<sub>max</sub> may be a non-invasive and readily available surrogate indicator for %ctDNA, a prognostic factor for patient survival. Since higher %ctDNA has been previously correlated with worse outcome, the relationship between SUV<sub>max</sub>, %ctDNA and survival warrants further study.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414395/pdf/ajnmmi0011-0307.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Small target repeatability of <sup>68</sup>Ga and <sup>18</sup>F: effects of target concentration and imaging time on SUV measurements in clinically relevant phantoms.","authors":"Michael S Silosky, Luke W Patten, Bennett B Chin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Quantification of tumor uptake using PET imaging is important for the evaluation of therapy response. For <sup>18</sup>F FDG PET scans, a change in uptake of 25% is commonly considered significant. For scans using novel radiopharmaceuticals, the threshold of significance is unclear. Factors including imaging time, tumor size, activity concentration, and radiopharmaceutical may affect the repeatablity of uptake metrics. This work evaluates the effect of these parameters on the repeatablity of maximum SUV (SUV<sub>max</sub>) and mean SUV (SUV<sub>mean</sub>) in phantoms using <sup>18</sup>F and <sup>68</sup>Ga. An Esser PET phantom (Data Spectrum, Durham NC) was scanned on a Biograph Horizon PET/CT scanner (Siemens Medical Solutions, Malvern PA) using <sup>18</sup>F and <sup>68</sup>Ga. Data were acquired for 5 minutes with reconstructions between 0.5-5 minutes. The background activity mimicked clinical scans with target-to-background (T/B) ratios from 1.7-19.8. The SUV<sub>max</sub> and SUV<sub>mean</sub> were measured for 5 slices. The mean, standard deviation, and coefficient of variation (COV) were calculated. The effects of radionuclide, imaging time, activity concentration, and target size on COV were evaluated using multivariate gamma regressions. COV for <sup>68</sup>Ga was 40% higher and 54% higher on average than for <sup>18</sup>F for SUV<sub>max</sub> and SUV<sub>mean</sub>, respectively. Decreased lesion size, imaging time, and activity concentration were significantly associated with increased COV for both metrics (P < 0.001). COV was substantially reduced at high T/B for <sup>68</sup>Ga. At the highest T/B the COV for SUV<sub>max</sub> and SUV<sub>mean</sub> was within the typical range seen for <sup>18</sup>F. COV is relatively high for small targets (8 mm) but is dramatically reduced with high radiotracer uptake.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414403/pdf/ajnmmi0011-0280.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zijian Zhou, Preetesh Jain, Yang Lu, Homer Macapinlac, Michael L Wang, Jong Bum Son, Mark D Pagel, Guofan Xu, Jingfei Ma
{"title":"Computer-aided detection of mantle cell lymphoma on <sup>18</sup>F-FDG PET/CT using a deep learning convolutional neural network.","authors":"Zijian Zhou, Preetesh Jain, Yang Lu, Homer Macapinlac, Michael L Wang, Jong Bum Son, Mark D Pagel, Guofan Xu, Jingfei Ma","doi":"","DOIUrl":"","url":null,"abstract":"<p><p><sup>18</sup>F-FDG PET/CT can provide quantitative characterization with prognostic value for mantle cell lymphoma (MCL). However, detection of MCL is performed manually, which is labor intensive and not a part of the routine clinical practice. This study investigates a deep learning convolutional neural network (DLCNN) for computer-aided detection of MCL on <sup>18</sup>F-FDG PET/CT. We retrospectively analyzed 142 baseline <sup>18</sup>F-FDG PET/CT scans of biopsy-confirmed MCL acquired between May 2007 and October 2018. Of the 142 scans, 110 were from our institution and 32 were from outside institutions. An Xception-based U-Net was constructed to classify each pixel of the PET/CT images as MCL or not. The network was first trained and tested on the within-institution scans by applying five-fold cross-validation. Sensitivity and false positives (FPs) per patient were calculated for network evaluation. The network was then tested on the outside-institution scans, which were excluded from network training. For the 110 within-institution patients (85 male; median age, 58 [range: 39-84] years), the network achieved an overall median sensitivity of 88% (interquartile range [IQR]: 25%) with 15 (IQR: 12) FPs/patient. Sensitivity was dependent on lesion size and SUV<sub>max</sub> but not on lesion location. For the 32 outside-institution patients (24 male; median age, 59 [range: 40-67] years), the network achieved a median sensitivity of 84% (IQR: 24%) with 14 (IQR: 10) FPs/patient. No significant performance difference was found between the within and outside institution scans. Therefore, DLCNN can potentially help with MCL detection on <sup>18</sup>F-FDG PET/CT with high sensitivity and limited FPs.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414404/pdf/ajnmmi0011-0260.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New wine in old bottles: <sup>68</sup>Ga-PSMA-11 PET/CT reveals COVID-19 in patients with prostate cancer.","authors":"Hanyi Fang, Muhsin H Younis, Weibo Cai, Xiaoli Lan, Dawei Jiang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The COVID-19 pandemic continues to influence every aspect of human life across the globe. It was reported that vascular angiogenesis of COVID-19 was elevated in patients with equally severe influenza virus infection. In this issue of AJNMMI, Farolfi et al. reported that there was lung uptake not related to prostate cancer in almost all COVID-19 patients who performed <sup>68</sup>Ga-PSMA-11 PET/CT scans and most of the lung uptake lesions were matched with typical CT patterns of COVID-19. With the advantages of having various tracers for whole-body imaging, PET provides opportunities to study the mechanism of COVID-19 from different aspects and obtain patterns of extrapulmonary lesions in COVID-19, which helps explore more effective treatments for the patients. This case series opened the door to many future studies. Furthermore, such a multi-national/multi-institutional collaboration in the pandemic truly encouraged us that science is indeed without borders.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414401/pdf/ajnmmi0011-0332.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39410004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David Gelston, Samantha C Brosler, Jennifer Vazquez, Olivia Sorci, A Huntington Griffith, Shampa Chatterjee, Anna Buchner, Poul F Høilund-Carlsen, Abass Alavi, Chamith S Rajapakse
{"title":"Utility of FDG PET/CT in assessing bowel inflammation.","authors":"David Gelston, Samantha C Brosler, Jennifer Vazquez, Olivia Sorci, A Huntington Griffith, Shampa Chatterjee, Anna Buchner, Poul F Høilund-Carlsen, Abass Alavi, Chamith S Rajapakse","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To develop a methodology for the quantification of gastrointestinal (GI) inflammation as indicated by 2-deoxy-2-(<sup>18</sup>F)fluoro-D-glucose (FDG) uptake on positron-emissions tomography/computed tomography (PET/CT) imaging. This is intended to investigate the feasibility of using standard uptake value (SUV) levels to assess levels of GI inflammation in humans.</p><p><strong>Methods: </strong>131 participants were injected with a weight-controlled dose of FDG 180 minutes prior to PET/CT scanning. Operator-guided software was used to segment the GI tract and perform (SUV) calculations. Regions of interest (ROIs) were created using CT images and stacked to create three dimensional volumes of interest (VOIs). These VOIs defined 6 sections of the GI tract: esophagus, stomach, descending colon, ascending and transverse colon, bowel below the ilium and small bowel above the ilium.</p><p><strong>Results: </strong>This study found a significant correlation between age and average FDG uptake (avg-SUV) of the GI tract (P=.0003) with the esophagus showing the highest significance. Correlations were found between avg-SUV of the sigmoid segment and the group average (P<.0001), and between the descending colon VOI and the group (P<.0001). Intra-operator reproducibility over 3 trials showed a coefficient of variation (CV) of .63%. Inter-operator CV over 5 randomly selected patients was 5.6% over the entire GI tract.</p><p><strong>Conclusion: </strong>This study shows that FDG-PET/CT imaging is a promising technique for quantifying bowel inflammation, despite the fact that age related inflammation may not be of clinical utility. The fact that we were able to detect these subtle changes indicates this as an avenue for potential future investigation.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414397/pdf/ajnmmi0011-0271.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"HPLC-free and cassette-based nucleophilic production of [<sup>18</sup>F]FDOPA for clinical use.","authors":"Huailei Jiang, Manoj K Jain, Hancheng Cai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Radiotracer 3,4-dihydroxy-6-[<sup>18</sup>F]fluoro-L-phenylalanine (L-6-[<sup>18</sup>F]fluorodopa or [<sup>18</sup>F]FDOPA) is widely used for PET imaging of dopamine metabolism in several diseases including Parkinson's Disease, brain tumor, neuroendocrine tumors, and focal hyperinsulinism of infancy. In 2019, [<sup>18</sup>F]FDOPA was approved by US FDA for detection of dopaminergic nerve terminals in the striatum of adult patients with suspected Parkinsonian Syndromes. A convenient and reliable method is desired for fully automated production of [<sup>18</sup>F]FDOPA under cGMP compliance to meet the increasing clinical need. In this study, we reported a cassette-based automated production of [<sup>18</sup>F]FDOPA using a GE Fastlab 2 module and the quality control (QC) under fully cGMP compliant environment. Briefly, automated radiosynthesis of [<sup>18</sup>F]FDOPA was processed via nucleophilic radio-fluorination using FDOPA Fastlab cassette and solid phase extraction (SPE) purification. The QC tests of [<sup>18</sup>F]FDOPA, including appearance, pH, half-life, radiochemical purity and identity, enantiomeric purity, chemical impurities, molecular activity, radioactive concentration, filter integrity, endotoxin, and sterility, were conducted at the end of synthesis (EOS) and 8 h after EOS during the validation runs. Three consecutive productions of [<sup>18</sup>F]FDOPA were reliably achieved with desired radiochemical yield and high radiochemical/enantiomeric purities and molar activity. The uncorrected radiochemical yields of [<sup>18</sup>F]FDOPA were 9.3-9.8% with a total synthesis time of ~140 min. Both radiochemical and enantiomeric purities of [<sup>18</sup>F]FDOPA were >99.9% and the molar activities were 2.1-3.9 Ci/μmole at EOS. The full QC results at EOS and 8 h after EOS showed that the produced [<sup>18</sup>F]FDOPA met all release criteria for clinical use within 8 hours of expiration time. Three consecutive validation runs and QC results demonstrated the efficacy of cassette-based production of [<sup>18</sup>F]FDOPA for routine clinical use.</p>","PeriodicalId":7572,"journal":{"name":"American journal of nuclear medicine and molecular imaging","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8414396/pdf/ajnmmi0011-0290.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}