Dataset Information

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted ¹⁸F-DCFPyL PET/CT.

ABSTRACT:

Objective

Complete surgical resection of metastatic sites has been shown to prolong survival in select patients with oligometastatic RCC. This treatment strategy is dependent upon the accurate characterization of a patient's extent of disease. The objective of this study was to explore the utility of PSMA-targeted ¹⁸F-DCFPyL PET/CT in patients with presumed oligometastatic clear cell RCC.

Methods

This is a subset analysis of a prospective study in which patients with RCC were imaged with ¹⁸F-DCFPyL PET/CT (ClinicalTrials.gov identifier NCT02687139). In the present analysis, patients with oligometastatic clear cell RCC, defined as ≤ 3 metastatic lesions on conventional imaging, were evaluated. ¹⁸F-DCFPyL PET/CT scans were reviewed for sites of disease and compared to conventional imaging.

Results

The final cohort included 14 patients with oligometastatic clear cell RCC. Conventional imaging revealed 21 metastatic lesions and 3 primary tumors. ¹⁸F-DCFPyL PET/CT detected 29 sites of metastatic disease and 3 primary tumors. Of the 21 metastatic lesions detected on conventional imaging, 17 (81.0%) had radiotracer uptake. Additionally, all 3 primary tumors had radiotracer uptake. In 4 (28.6%) patients a total of 12 more lesions were identified on ¹⁸F-DCFPyL PET/CT than conventional imaging. Notably, 3 (21.4%) patients were no longer considered oligometastatic. The detection rates of conventional imaging and ¹⁸F-DCFPyL PET/CT for identifying sites of disease were 66.7% and 88.9%, respectively.

Conclusions

PSMA-targeted PET/CT appears to aid in the identification of patients with oligometastatic clear cell RCC. If borne out in future studies, this suggests that PSMA-targeted imaging has the potential to help select candidates for metastasis-directed therapy.

SUBMITTER: Meyer AR

PROVIDER: S-EPMC9774684 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Publications

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted <sup>18</sup>F-DCFPyL PET/CT.

Meyer Alexa R AR Carducci Michael A MA Denmeade Samuel R SR Markowski Mark C MC Pomper Martin G MG Pierorazio Philip M PM Allaf Mohamad E ME Rowe Steven P SP Gorin Michael A MA

Annals of nuclear medicine 20190530 8

<h4>Objective</h4>Complete surgical resection of metastatic sites has been shown to prolong survival in select patients with oligometastatic RCC. This treatment strategy is dependent upon the accurate characterization of a patient's extent of disease. The objective of this study was to explore the utility of PSMA-targeted <sup>18</sup>F-DCFPyL PET/CT in patients with presumed oligometastatic clear cell RCC.<h4>Methods</h4>This is a subset analysis of a prospective study in which patients with RC ...[more]

PMID: 31147927

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Project description:Recently, the standardized reporting and data system for prostate-specific membrane antigen (PSMA)-targeted PET imaging studies, termed PSMA-RADS version 1.0, was introduced. We aimed to determine the interobserver agreement for applying PSMA-RADS to imaging interpretation of 18F-DCFPyL (2-(3-{1-carboxy-5-[(6-18F-fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid) PET examinations in a prospective setting mimicking the typical clinical workflow at a prostate cancer referral center. Methods: Four readers (2 experienced readers (ERs, >3 y of PSMA-targeted PET interpretation experience) and 2 inexperienced readers (IRs, <1 y of experience)), who had all read the initial publication on PSMA-RADS 1.0, assessed 50 18F-DCFPyL PET/CT studies independently. Per scan, a maximum of 5 target lesions was selected by the observers, and a PSMA-RADS score for every target lesion was recorded. No specific preexisting conditions were placed on the selection of the target lesions, although PSMA-RADS 1.0 suggests that readers focus on the most avid or largest lesions. An overall scan impression based on PSMA-RADS was indicated, and interobserver agreement rates on a target lesion-based, on an organ-based, and on an overall PSMA-RADS score-based level were computed. Results: The number of target lesions identified by each observer was as follows: ER 1, 123; ER 2, 134; IR 1, 123; and IR 2, 120. Among those selected target lesions, 125 were chosen by at least 2 individual observers (all 4 readers selected the same target lesion in 58 of 125 [46.4%] instances, 3 readers in 40 of 125 [32%], and 2 observers in 27 of 125 [21.6%]). The interobserver agreement for PSMA-RADS scoring among identical target lesions was good (intraclass correlation coefficient [ICC] for 4, 3, and 2 identical target lesions, ≥0.60, respectively). For lymph nodes, an excellent interobserver agreement was derived (ICC, 0.79). The interobserver agreement for an overall scan impression based on PSMA-RADS was also excellent (ICC, 0.84), with a significant difference for ER (ICC, 0.97) vs. IR (ICC, 0.74) (P = 0.005). Conclusion: PSMA-RADS demonstrated a high concordance rate in this study, even among readers with different levels of experience. This finding suggests that PSMA-RADS can be effectively used for communication with clinicians and can be implemented in the collection of data for large prospective trials.

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Project description:Quantitative evaluation of radiolabeled prostate-specific membrane antigen (PSMA) PET scans may be used to monitor treatment response in patients with prostate cancer (PCa). To interpret longitudinal differences in PSMA uptake, the intrinsic variability of tracer uptake in PCa lesions needs to be defined. The aim of this study was to investigate the repeatability of quantitative PET/CT measurements using 18F-DCFPyL ([2-(3-(1-carboxy-5-[(6-18F-fluoro-pyridine-3-carbonyl)-amino]-pentyl)-ureido)-pentanedioic acid], a second-generation 18F-PSMA-ligand) in patients with PCa. Methods: Twelve patients with metastatic PCa were prospectively included, of whom 2 were excluded from final analyses. Patients received 2 whole-body 18F-DCFPyL PET/CT scans (median dose, 317 MBq; uptake time, 120 min) within a median of 4 d (range, 1-11 d). After semiautomatic (isocontour-based) tumor delineation, the following lesion-based metrics were derived: mean, peak, and maximum tumor-to-blood ratio; SUVmean, SUVpeak, and SUVmax normalized to body weight; tumor volume; and total lesion uptake (TLU). Additionally, patient-based total tumor volume (TTV) (sum of PSMA-positive tumor volumes) and total tumor burden (TTB) (sum of all lesion TLUs) were derived. Repeatability was analyzed using repeatability coefficients (RC) and intraclass correlation coefficients. Additionally, the effect of point-spread function (PSF) image reconstruction on the repeatability of uptake metrics was evaluated. Results: In total, 36 18F-DCFPyL PET-positive lesions were analyzed (≤5 lesions per patient). The RCs for mean, peak, and maximum tumor-to-blood ratio were 31.8%, 31.7%, and 37.3%, respectively. For SUVmean, SUVpeak, and SUVmax, the RCs were 24.4%, 25.3%, and 31.0%, respectively. All intraclass correlation coefficients were at least 0.97. Tumor volume delineations were quite repeatable, with an RC of 28.1% for individual lesion volumes and 17.0% for TTV. TTB had an RC of 23.2% and 33.4% when based on SUVmean and mean tumor-to-blood ratio, respectively. Small lesions (<4.2 cm3) had worse repeatability for volume measurements. The repeatability of SUVpeak, TLU, and all patient-level metrics was not affected by PSF reconstruction. Conclusion: 18F-DCFPyL uptake measurements are quite repeatable and can be used for clinical validation in future treatment response assessment studies. Patient-based TTV may be preferred for multicenter studies because its repeatability was both high and robust to different image reconstructions.

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Dataset Information

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted ¹⁸F-DCFPyL PET/CT.

Objective

Methods

Results

Conclusions

Publications

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted <sup>18</sup>F-DCFPyL PET/CT.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted 18F-DCFPyL PET/CT.

Objective

Methods

Results

Conclusions

Publications

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted <sup>18</sup>F-DCFPyL PET/CT.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Improved identification of patients with oligometastatic clear cell renal cell carcinoma with PSMA-targeted ¹⁸F-DCFPyL PET/CT.