Physiological Biodistribution of 18F-fluciclovine in The Head

Physiological Biodistribution of 18F-fluciclovine in The Head | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Physiological Biodistribution of 18 F-fluciclovine in The Head Yumi Abe, Ryogo Minamimoto, Naotoshi Fujita, Marina Higashi, Rintaro Ito, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7935567/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: Anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid (18F-fluciclovine; anti-3-[18F]FACBC) is an amino acid positron emission tomography (PET) tracer used for the evaluation of brain tumors in cases of suspected or diagnosed glioma. However, reports on the physiological biodistribution of 18F-fluciclovine in the head, are limited. This study retrospectively analyzed the physiological biodistribution of 18F-fluciclovine PET in the head. Methods: We analyzed 18F-fluciclovine PET/CT images of 20 patients who were suspected of malignant glioma. The maximum and mean standard uptake values (SUVmax and SUVmean) were measured in the 24 areas of the head tissues. Time-activity curves were generated, with the volume of index placed in the same manner as for the SUV measurements to obtain dynamic uptake over time. Differences in SUV between regions were assessed using one-way analysis of variance. Among 20 patients who received 18F-fluciclovine PET/CT, physiological biodistribution analyses were performed in 8 patients who also underwent 11C- methionine PET/CT. Comparisons of SUV between 18F-fluciclovine and 11C-methionine PET were performed using paired t-tests. Statistical significance was set at P < 0.05 for all analyses. Results: 18F-fluciclovine uptake in the cerebral cortex was uniformly low (mean SUVmean 0.3 ± 0.1), with slightly higher values in the basal ganglia, thalamus, midbrain, pons, medulla oblongata, cerebellum, and cerebellar vermis (0.4 ± 0.1). Among extracerebral regions, the highest uptake was in the parotid gland (3.4 ± 0.8), followed by the pharynx (2.5 ± 0.5), pituitary gland, nasal cavity (2.3 ± 0.4), muscle (2.2 ± 0.6), bone marrow (2.0 ± 0.5), and skin (1.9 ± 0.6). In 15 patients, brain uptake remained low and stable, while the pituitary gland and parotid glands peaked immediately after injection and declined rapidly. In 8 patients with 11C-methionine PET, methionine showed significantly higher uptake in all brain regions, whereas 18F-fluciclovine was higher in the venous sinus, cavernous sinus, muscle, and nasal cavity. Conclusion: Understanding these physiological biodistribution patterns of 18F-fluciclovine PET is essential for distinguishing between pathological uptake patterns and for providing useful baseline data. Furthermore, 18F-fluciclovine uptake in the brain was uniformly low in the cerebral cortex, with minimal nonspecific uptake, suggesting that it may contribute to defining tumor margins. 18F-fluciclovine physiological biodistribution standardized uptake value amino acid positron emission tomography Figures Figure 1 Figure 2 Figure 3 Figure 4 Full Text Additional Declarations Table 1 is available in the Supplementary Files section Supplementary Files Table.pdf OnlineResources.pdf Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7935567","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":534699491,"identity":"f9c51f33-109b-42eb-8499-b6f36820accc","order_by":0,"name":"Yumi 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1","display":"","copyAsset":false,"role":"figure","size":1135473,"visible":true,"origin":"","legend":"\u003cp\u003eManual VOIs in each area of the head Axial fused PET/CT images are shown. (a) Frontal lobe, parietal lobe, white matter and skin (arrow); (b) choroid plexus; (c) temporal lobe and occipital lobe; (d) basal ganglia, thalamus and pineal gland; (e) midbrain and venous sinus; (f) lacrimal gland and cerebellar vermis; (g) cavernous sinus, pituitary gland, pons and cerebellum; (h) medulla oblongata; and (i) nasal cavity, parotid gland, pharynx, bone marrow, and muscle. Three spherical VOIs (1.5 cm in diameter) were manually placed in the contralateral normal cerebral cortex of each region.\u003c/p\u003e","description":"","filename":"Fig.1.png","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/02574fb6f295e0c1d76236ad.png"},{"id":95240011,"identity":"3b00d14a-593b-45c3-b342-a26ae7a6ab1f","added_by":"auto","created_at":"2025-11-05 19:00:58","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6113990,"visible":true,"origin":"","legend":"\u003cp\u003eSUVs in intracerebral regions, a) SUVmax, b) SUVmean, c) SUVpeak FL: frontal lobe, PL: parietal lobe, TL: temporal lobe, OL: occipital lobe, WM: white matter, Th: thalamus, BG: basal ganglia, MB: midbrain, Pons: pons, MO: medulla oblongata, Cb: cerebellum, Vermis: cerebellar vermis. 18F-fluciclovine uptake in the cerebral cortex was low. Slightly higher uptakes were observed in the basal ganglia, thalamus, midbrain, pons, medulla, cerebellum, and cerebellar vermis than in the cerebral cortex. 18F-fluciclovine head uptake\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/d16a5306bc1685a99399753c.png"},{"id":95240012,"identity":"0c6d1b36-11ad-4af4-a3a5-472ce9370449","added_by":"auto","created_at":"2025-11-05 19:00:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":3737139,"visible":true,"origin":"","legend":"\u003cp\u003eSUVs in extracerebral regions, a) SUVmax, b) SUVmean Pit: pituitary gland, PiG: pineal gland, CP: choroid plexus, VS: venous sinus, CS: cavernous sinus, LG: lacrimal gland, PG: parotid gland, Ph: pharynx, NC: nasal cavity, Ms: muscle, BM: bone marrow, and Sk: skin. 18F-fluciclovine uptake was the highest in the parotid gland, followed by the pharynx, pituitary gland, nasal cavity, muscle, bone marrow, and skin.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/cfa78e833f4c7759b9f7ab07.png"},{"id":95312497,"identity":"55a63d5b-e0a1-4536-9031-92d07eaef3da","added_by":"auto","created_at":"2025-11-06 15:49:32","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":2914589,"visible":true,"origin":"","legend":"\u003cp\u003eTime-activity curves, a) intracerebral, b) extracerebral regions FL: frontal lobe, PL: parietal lobe, TL: temporal lobe, OL: occipital lobe, WM: white matter, Th: thalamus, BG: basal ganglia, MB: midbrain, Pons: pons, MO: medulla oblongata, Cb: cerebellum, Vermis: cerebellar vermis, Pit: pituitary gland, PiG: pineal gland, CP: choroid plexus, VS: venous sinus, CS: cavernous sinus, LG: lacrimal gland, PG: parotid gland, Ph: pharynx, NC: nasal cavity, Ms: muscle, BM: bone marrow, and Sk: skin. 18F-fluciclovine uptake remained low across all brain regions, with no significant changes in SUV over time. In the extracerebral regions, the pituitary and parotid gland showed peak uptake immediately after injection, followed by a marked decline over 18F-fluciclovine head uptake time. Gradual decreases were observed in the choroid plexus, venous sinus, cavernous sinus, lacrimal gland, pharynx, nasal cavity, and bone marrow.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/84bbf58792f56954af3c1084.png"},{"id":96251717,"identity":"7e09d06a-8b0f-455c-9bab-3b0153e7e901","added_by":"auto","created_at":"2025-11-19 07:39:58","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5426351,"visible":true,"origin":"","legend":"","description":"","filename":"fluciclovinemanuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1_covered_5052f612-cd33-481f-bb26-93b1250b2ed8.pdf"},{"id":95240013,"identity":"61e35ea3-94e9-43e4-acfe-0e2d160f4446","added_by":"auto","created_at":"2025-11-05 19:00:58","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":186291,"visible":true,"origin":"","legend":"","description":"","filename":"Table.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/4c69d6583db667750ab19ef6.pdf"},{"id":95240015,"identity":"cec994b8-ba27-4b8c-97ce-bc2747a0a37d","added_by":"auto","created_at":"2025-11-05 19:00:58","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":586047,"visible":true,"origin":"","legend":"","description":"","filename":"OnlineResources.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7935567/v1/b463076dd5f8b6b2da3a825b.pdf"}],"financialInterests":"\u003cp\u003eTable 1 is available in the Supplementary Files section\u003c/p\u003e","formattedTitle":"\u003cp\u003ePhysiological Biodistribution of \u003csup\u003e18\u003c/sup\u003eF-fluciclovine in The Head\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"18F-fluciclovine, physiological biodistribution, standardized uptake value, amino acid positron emission tomography","lastPublishedDoi":"10.21203/rs.3.rs-7935567/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7935567/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective:\u003c/strong\u003e\u0026nbsp;Anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid (18F-fluciclovine; anti-3-[18F]FACBC) is an amino acid positron emission tomography (PET) tracer used for the evaluation of brain tumors in cases of suspected or diagnosed glioma. However, reports on the physiological biodistribution of 18F-fluciclovine in the head, are limited. This study retrospectively analyzed the physiological biodistribution of 18F-fluciclovine PET in the head. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe analyzed 18F-fluciclovine PET/CT images of 20 patients who were suspected of malignant glioma. The maximum and mean standard uptake values (SUVmax and SUVmean) were measured in the 24 areas of the head tissues. Time-activity curves were generated, with the volume of index placed in the same manner as for the SUV measurements to obtain dynamic uptake over time. Differences in SUV between regions were assessed using one-way analysis of variance. Among 20 patients who received 18F-fluciclovine PET/CT, physiological biodistribution analyses were performed in 8 patients who also underwent 11C- methionine PET/CT. Comparisons of SUV between 18F-fluciclovine and 11C-methionine PET were performed using paired t-tests. Statistical significance was set at P \u0026lt; 0.05 for all analyses. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u0026nbsp;\u003c/strong\u003e 18F-fluciclovine uptake in the cerebral cortex was uniformly low (mean SUVmean 0.3 ± 0.1), with slightly higher values in the basal ganglia, thalamus, midbrain, pons, medulla oblongata, cerebellum, and cerebellar vermis (0.4 ± 0.1). Among extracerebral regions, the highest uptake was in the parotid gland (3.4 ± 0.8), followed by the pharynx (2.5 ± 0.5), pituitary gland, nasal cavity (2.3 ± 0.4), muscle (2.2 ± 0.6), bone marrow (2.0 ± 0.5), and skin (1.9 ± 0.6). In 15 patients, brain uptake remained low and stable, while the pituitary gland and parotid glands peaked immediately after injection and declined rapidly. In 8 patients with 11C-methionine PET, methionine showed significantly higher uptake in all brain regions, whereas 18F-fluciclovine was higher in the venous sinus, cavernous sinus, muscle, and nasal cavity. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e Understanding these physiological biodistribution patterns of 18F-fluciclovine PET is essential for distinguishing between pathological uptake patterns and for providing useful baseline data. Furthermore, 18F-fluciclovine uptake in the brain was uniformly low in the cerebral cortex, with minimal nonspecific uptake, suggesting that it may contribute to defining tumor margins.\u003c/p\u003e","manuscriptTitle":"Physiological Biodistribution of 18F-fluciclovine in The Head","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-05 19:00:53","doi":"10.21203/rs.3.rs-7935567/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7604ba36-a7f1-4d8b-a059-96b2aac91691","owner":[],"postedDate":"November 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-19T00:20:17+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-05 19:00:53","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7935567","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7935567","identity":"rs-7935567","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}