Performance of68Ga-PSMA-11 PET/CT for Diagnosing Tumor Thrombus and Predicting Response to Pembrolizumab and Axitinib in Patients with Renal Cell Carcinoma: A Pilot, Retrospective Study.
{"title":"Performance of<sup>68</sup>Ga-PSMA-11 PET/CT for Diagnosing Tumor Thrombus and Predicting Response to Pembrolizumab and Axitinib in Patients with Renal Cell Carcinoma: A Pilot, Retrospective Study.","authors":"Bo-Han Lin, Cheng-Long Zeng, Xiao-Hui Wu, Rui-Cheng Gao, Qian-Ren-Shun Qiu, Ye-Hui Chen, Xue-Yi Xue, Qing-Shui Zheng, Shao-Hao Chen, Yong Wei, Ning Xu","doi":"10.1245/s10434-026-20772-4","DOIUrl":null,"url":null,"abstract":"<p><strong>Objectives: </strong>To investigate the performance of <sup>68</sup>Ga-PSMA-11 PET/CT for diagnosing tumor thrombus (TT) and predicting response to pembrolizumab and axitinib in renal cell carcinoma (RCC) with TT.</p><p><strong>Methods: </strong>We reviewed RCC patients who underwent contrast-enhanced CT, mpMRI, and <sup>68</sup>Ga-PSMA-11 PET/CT. Diagnostic performance for detecting TT was analyzed, with TT confirmed by experienced pathologists. We further analyzed clear cell RCC (ccRCC) patients with TT who received pembrolizumab and axitinib and evaluated imaging features for predicting therapeutic efficacy by using receiver operating characteristic analysis. Internal validation was performed using bootstrap resampling (1000 iterations). Model calibration was assessed with the Hosmer-Lemeshow test.</p><p><strong>Results: </strong>A total of 166 RCC patients were initially included, of whom 56 had TT. <sup>68</sup>Ga-PSMA-11 PET/CT showed higher overall diagnostic performance for TT than contrast-enhanced CT and mpMRI, with incremental detection primarily observed for Mayo level 0-I TT. The sensitivity and specificity of PET/CT in diagnosing TT were 0.96 (95% CI 0.88-0.99) and 0.97 (95% CI 0.92-0.99), respectively. Then, 35 ccRCC patients with TT underwent an average of 5 cycles of pembrolizumab and axitinib, followed by surgery. Following neoadjuvant therapy, 21 patients exhibited a partial response, while 14 showed nonresponse. TT SUVmax demonstrated significant predictive value for response to neoadjuvant therapy, with an AUC of 0.80 (95% CI 0.63-0.92; bootstrap-corrected, 0.79). The Hosmer-Lemeshow test indicated adequate calibration (P > 0.05).</p><p><strong>Conclusions: </strong><sup>68</sup>Ga-PSMA-11 PET/CT may provide incremental value for detecting low-level TT and shows potential for predicting response to pembrolizumab plus axitinib in RCC. However, the clinical significance of detecting early TT remains uncertain.</p>","PeriodicalId":8229,"journal":{"name":"Annals of Surgical Oncology","volume":" ","pages":""},"PeriodicalIF":3.8000,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Surgical Oncology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1245/s10434-026-20772-4","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Objectives: To investigate the performance of 68Ga-PSMA-11 PET/CT for diagnosing tumor thrombus (TT) and predicting response to pembrolizumab and axitinib in renal cell carcinoma (RCC) with TT.
Methods: We reviewed RCC patients who underwent contrast-enhanced CT, mpMRI, and 68Ga-PSMA-11 PET/CT. Diagnostic performance for detecting TT was analyzed, with TT confirmed by experienced pathologists. We further analyzed clear cell RCC (ccRCC) patients with TT who received pembrolizumab and axitinib and evaluated imaging features for predicting therapeutic efficacy by using receiver operating characteristic analysis. Internal validation was performed using bootstrap resampling (1000 iterations). Model calibration was assessed with the Hosmer-Lemeshow test.
Results: A total of 166 RCC patients were initially included, of whom 56 had TT. 68Ga-PSMA-11 PET/CT showed higher overall diagnostic performance for TT than contrast-enhanced CT and mpMRI, with incremental detection primarily observed for Mayo level 0-I TT. The sensitivity and specificity of PET/CT in diagnosing TT were 0.96 (95% CI 0.88-0.99) and 0.97 (95% CI 0.92-0.99), respectively. Then, 35 ccRCC patients with TT underwent an average of 5 cycles of pembrolizumab and axitinib, followed by surgery. Following neoadjuvant therapy, 21 patients exhibited a partial response, while 14 showed nonresponse. TT SUVmax demonstrated significant predictive value for response to neoadjuvant therapy, with an AUC of 0.80 (95% CI 0.63-0.92; bootstrap-corrected, 0.79). The Hosmer-Lemeshow test indicated adequate calibration (P > 0.05).
Conclusions: 68Ga-PSMA-11 PET/CT may provide incremental value for detecting low-level TT and shows potential for predicting response to pembrolizumab plus axitinib in RCC. However, the clinical significance of detecting early TT remains uncertain.
期刊介绍:
The Annals of Surgical Oncology is the official journal of The Society of Surgical Oncology and is published for the Society by Springer. The Annals publishes original and educational manuscripts about oncology for surgeons from all specialities in academic and community settings.