{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T18:13:20Z","timestamp":1788459200232,"version":"build-2803163510"},"reference-count":21,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T00:00:00Z","timestamp":1788393600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015375","name":"Affiliated Hospital of Southwest Medical University","doi-asserted-by":"publisher","award":["2021ZKQN054"],"award-info":[{"award-number":["2021ZKQN054"]}],"id":[{"id":"10.13039\/501100015375","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015375","name":"Affiliated Hospital of Southwest Medical University","doi-asserted-by":"publisher","award":["2022QN055"],"award-info":[{"award-number":["2022QN055"]}],"id":[{"id":"10.13039\/501100015375","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n Background<\/jats:title>\n \n Thyroglobulin (Tg) is a standard biomarker for monitoring differentiated thyroid carcinoma (DTC) after radioiodine therapy, yet its reliability is compromised by false-positive and false-negative results. This study aimed to evaluate the diagnostic performance of\n 68<\/jats:sup>\n Ga-FAPI-04 PET\/CT, an emerging imaging modality, for detecting recurrence and metastasis in DTC patients, regardless of their Tg status.\n <\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n This retrospective study included patients with suspected or confirmed metastatic DTC who underwent\n 68<\/jats:sup>\n Ga-FAPI-04 PET\/CT between October 2022 and May 2025. All participants underwent\n 68<\/jats:sup>\n Ga-FAPI-04 PET\/CT and Tg testing, with histopathology or clinical follow-up as the reference standard. The sensitivity, specificity, and accuracy of both methods were compared. Quantitative analysis was performed using the target-to-background ratio (TBR).\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Among 99 patients in a TSH-suppressed state,\n 68<\/jats:sup>\n Ga-FAPI-04 PET\/CT demonstrated superior diagnostic accuracy (95.96%) compared to Tg testing (91.92%). In 48 TSH-stimulated patients, PET\/CT maintained perfect accuracy (100%), outperforming Tg (97.92%). Notably, PET\/CT successfully identified metastatic lesions in eight Tg-negative patients, primarily lymph node metastases. Using the mediastinum as a background for TBR calculation further enhanced the diagnostic efficacy for lymph node metastases, with the optimal threshold being 1.428, and achieving an accuracy and true positive rate of 0.98.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n 68<\/jats:sup>\n Ga\u2011FAPI\u201104 PET\/CT exhibits high accuracy for diagnosing recurrence and metastasis in DTC, and importantly can identify lesions in Tg\u2011negative patients.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0355343","type":"journal-article","created":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T17:21:01Z","timestamp":1788456061000},"page":"e0355343","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["68Ga-FAPI-04 PET\/CT has high diagnostic efficacy in Tg-positive and Tg-negative differentiated thyroid cancer"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4183-4063","authenticated-orcid":true,"given":"Lixian","family":"Mou","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ting","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoling","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0052-7817","authenticated-orcid":true,"given":"Wei","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,9,3]]},"reference":[{"issue":"4","key":"pone.0355343.ref001","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1016\/S2213-8587(22)00035-3","article-title":"The 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