Nils F. Trautwein, Sven Mattern, Martina Hinterleitner, Gerald Reischl, Ralf Schirrmacher, Volker Steger, Silvio Nadalin, Konstantin Nikolaou, Johannes Schwenck, Stephan Singer, Christian la Fougère
{"title":"[18F]SITATE生长抑素受体PET示踪剂的组织离体验证","authors":"Nils F. Trautwein, Sven Mattern, Martina Hinterleitner, Gerald Reischl, Ralf Schirrmacher, Volker Steger, Silvio Nadalin, Konstantin Nikolaou, Johannes Schwenck, Stephan Singer, Christian la Fougère","doi":"10.2967/jnumed.125.269619","DOIUrl":null,"url":null,"abstract":"<p>Radiolabeled somatostatin analogs (SSAs), such as [<sup>68</sup>Ga]Ga-DOTA SSAs, have transformed imaging and therapeutic strategies. However, their use is constrained by the high cost of generators and their short half-life. In contrast, [<sup>18</sup>F]SITATE presents a promising alternative, offering the advantage of a longer half-life than <sup>68</sup>Ga, along with the cost-effectiveness of cyclotron-based production. This study evaluated the first histologic ex vivo validation of [<sup>18</sup>F]SITATE. <strong>Methods:</strong> This study retrospectively included 47 patients (57% male; mean age, 66.9 ± 14.9 y) with histologically confirmed well-differentiated neuroendocrine neoplasms who underwent [<sup>18</sup>F]SITATE PET followed by surgery within 4 mo. Lesion uptake was quantified using SUV<sub>mean</sub>, SUV<sub>peak</sub>, SUV<sub>max</sub>, and tumor-to-liver ratio (TLR). Histologic somatostatin receptor (SSTR) type 2 expression was determined using histological scores (H-scores), with thresholds defining SSTR scores 1–3. The accuracy of PET imaging for preoperative metastatic detection was evaluated against surgical histology. <strong>Results:</strong> PET imaging demonstrated a significant correlation between [<sup>18</sup>F]SITATE uptake (SUV<sub>mean</sub> and TLR) and SSTR type 2 H-scores (<em>r</em> = 0.618 and 0.622, respectively; <em>P</em> < 0.0001). SSTR score 3 correlated with increased SUV<sub>mean</sub> and TLR (<em>P</em> < 0.0001). Among 35 patients with primary resection and lymphadenectomy, PET achieved a sensitivity of 73.9% and specificity of 100%. <strong>Conclusion:</strong> [<sup>18</sup>F]SITATE PET imaging strongly correlates with histologic SSTR expression, demonstrating utility in staging and guiding therapeutic decisions in neuroendocrine neoplasms. This <sup>18</sup>F-labeled tracer shows specificity comparable to historical [<sup>68</sup>Ga]Ga-DOTA SSA data, whereas an increase in sensitivity for the detection of locoregional metastases appears possible. Further head-to-head comparisons of [<sup>18</sup>F]SITATE with traditional [<sup>68</sup>Ga]Ga-DOTA SSA and histologic validation are warranted to optimize its diagnostic accuracy and clinical impact.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"35 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Histologic Ex Vivo Validation of the [18F]SITATE Somatostatin Receptor PET Tracer\",\"authors\":\"Nils F. Trautwein, Sven Mattern, Martina Hinterleitner, Gerald Reischl, Ralf Schirrmacher, Volker Steger, Silvio Nadalin, Konstantin Nikolaou, Johannes Schwenck, Stephan Singer, Christian la Fougère\",\"doi\":\"10.2967/jnumed.125.269619\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Radiolabeled somatostatin analogs (SSAs), such as [<sup>68</sup>Ga]Ga-DOTA SSAs, have transformed imaging and therapeutic strategies. However, their use is constrained by the high cost of generators and their short half-life. In contrast, [<sup>18</sup>F]SITATE presents a promising alternative, offering the advantage of a longer half-life than <sup>68</sup>Ga, along with the cost-effectiveness of cyclotron-based production. This study evaluated the first histologic ex vivo validation of [<sup>18</sup>F]SITATE. <strong>Methods:</strong> This study retrospectively included 47 patients (57% male; mean age, 66.9 ± 14.9 y) with histologically confirmed well-differentiated neuroendocrine neoplasms who underwent [<sup>18</sup>F]SITATE PET followed by surgery within 4 mo. Lesion uptake was quantified using SUV<sub>mean</sub>, SUV<sub>peak</sub>, SUV<sub>max</sub>, and tumor-to-liver ratio (TLR). Histologic somatostatin receptor (SSTR) type 2 expression was determined using histological scores (H-scores), with thresholds defining SSTR scores 1–3. The accuracy of PET imaging for preoperative metastatic detection was evaluated against surgical histology. <strong>Results:</strong> PET imaging demonstrated a significant correlation between [<sup>18</sup>F]SITATE uptake (SUV<sub>mean</sub> and TLR) and SSTR type 2 H-scores (<em>r</em> = 0.618 and 0.622, respectively; <em>P</em> < 0.0001). SSTR score 3 correlated with increased SUV<sub>mean</sub> and TLR (<em>P</em> < 0.0001). Among 35 patients with primary resection and lymphadenectomy, PET achieved a sensitivity of 73.9% and specificity of 100%. <strong>Conclusion:</strong> [<sup>18</sup>F]SITATE PET imaging strongly correlates with histologic SSTR expression, demonstrating utility in staging and guiding therapeutic decisions in neuroendocrine neoplasms. This <sup>18</sup>F-labeled tracer shows specificity comparable to historical [<sup>68</sup>Ga]Ga-DOTA SSA data, whereas an increase in sensitivity for the detection of locoregional metastases appears possible. Further head-to-head comparisons of [<sup>18</sup>F]SITATE with traditional [<sup>68</sup>Ga]Ga-DOTA SSA and histologic validation are warranted to optimize its diagnostic accuracy and clinical impact.</p>\",\"PeriodicalId\":22820,\"journal\":{\"name\":\"The Journal of Nuclear Medicine\",\"volume\":\"35 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2025-05-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Journal of Nuclear Medicine\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.2967/jnumed.125.269619\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Nuclear Medicine","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2967/jnumed.125.269619","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Histologic Ex Vivo Validation of the [18F]SITATE Somatostatin Receptor PET Tracer
Radiolabeled somatostatin analogs (SSAs), such as [68Ga]Ga-DOTA SSAs, have transformed imaging and therapeutic strategies. However, their use is constrained by the high cost of generators and their short half-life. In contrast, [18F]SITATE presents a promising alternative, offering the advantage of a longer half-life than 68Ga, along with the cost-effectiveness of cyclotron-based production. This study evaluated the first histologic ex vivo validation of [18F]SITATE. Methods: This study retrospectively included 47 patients (57% male; mean age, 66.9 ± 14.9 y) with histologically confirmed well-differentiated neuroendocrine neoplasms who underwent [18F]SITATE PET followed by surgery within 4 mo. Lesion uptake was quantified using SUVmean, SUVpeak, SUVmax, and tumor-to-liver ratio (TLR). Histologic somatostatin receptor (SSTR) type 2 expression was determined using histological scores (H-scores), with thresholds defining SSTR scores 1–3. The accuracy of PET imaging for preoperative metastatic detection was evaluated against surgical histology. Results: PET imaging demonstrated a significant correlation between [18F]SITATE uptake (SUVmean and TLR) and SSTR type 2 H-scores (r = 0.618 and 0.622, respectively; P < 0.0001). SSTR score 3 correlated with increased SUVmean and TLR (P < 0.0001). Among 35 patients with primary resection and lymphadenectomy, PET achieved a sensitivity of 73.9% and specificity of 100%. Conclusion: [18F]SITATE PET imaging strongly correlates with histologic SSTR expression, demonstrating utility in staging and guiding therapeutic decisions in neuroendocrine neoplasms. This 18F-labeled tracer shows specificity comparable to historical [68Ga]Ga-DOTA SSA data, whereas an increase in sensitivity for the detection of locoregional metastases appears possible. Further head-to-head comparisons of [18F]SITATE with traditional [68Ga]Ga-DOTA SSA and histologic validation are warranted to optimize its diagnostic accuracy and clinical impact.