aPROMISE: A Novel Automated PROMISE Platform to Standardize Evaluation of Tumor Burden in ¹⁸F-DCFPyL Images of Veterans with Prostate Cancer

Abstract

Rationale: Standardized staging and quantitative reporting is necessary to demonstrate the association of 18 F-DCFPyL PET/CT (PSMA) imaging with clinical outcome. This work introduces an automated platform to implement and extend the Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) criteria -aPROMISE. The objective is to validate the performance of aPROMISE in staging and quantifying disease burden in patients with prostate cancer who undergo PSMA Imaging.Methods: This was a retrospective analysis of 109 Veterans with intermediate and high-risk prostate cancer, who underwent PSMA imaging. To validate the performance of aPROMISE, two independent nuclear-medicine physicians conducted aPROMISEassisted reads, resulting in standardized reports that quantify individual lesions and stage the patients. Patients were staged as having local only disease (miN0M0); regional lymph node only (miN1M0), metastatic disease only (miN0M1), and with both regional and distant metastatic disease (miN1M1). The staging obtained from aPROMISE-assisted reads was compared with the staging by conventional imaging. Cohen's pairwise kappa agreement was used to evaluate the inter-reader variability. Correlation coefficient and ICC was used to evaluate the inter-reader variability of the quantitative assessment (miPSMA-index) in each stage. Kendall Tau and t-test was used to evaluate the association of miPSMA-index with PSA and Gleason Score.Results: All PSMA images of 109 veterans met the DICOM conformity and the requirements for the aPROMISE analysis. Both independent aPROMISE-assisted analyses demonstrated significant upstaging in patients with localized (23%; N=20/87) and regional tumor burden (25%; N=2/8). However, a significant number of patients with bone metastases identified on conventional imaging (NaF PET/CT) were downstaged (29%; N=4/14). The comparison of the two independent aPROMISE-assisted reads demonstrated a high kappa agreement -0.82 (miN0M0), 0.90 (miN1M0), and 0.77 (miN0M1). The Spearman correlation of quantitative miPSMA-index was 0.93, 0.96 and 0.97, respectively. As a continuous variable, miPSMA index in the prostate (miT) was associated with risk groups defined by the PSA and Gleason.. Conclusion:Here we demonstrate consistency of the aPROMISE platform between readers and observed substantial upstaging in PSMA imaging compared to the conventional imaging. aPROMISE may contribute to the broader standardization of PSMA imaging assessment and to its clinical utility in management of prostate cancer patients.

The 28th Annual Prostate Cancer Foundation Scientific Retreat report

“…aPROMISE was validated in a prospectively planned analysis of the OSPREY study 68 . Further validation of aPROMISE was demonstrated in a PCF‐VA study in veterans diagnosed with localized high‐risk prostate cancer imaged with PSMA PET/CT 69 …”

The other immuno-PET: Metabolic tracers in evaluation of immune responses to immune checkpoint inhibitor therapy for solid tumors

“…Automated quantitative image analysis overcomes the impracticality of manual measurement of all sites of interest and may allow extraction of predictive information relating to systemic immune responses. The advantages and promising clinical performance of the automated platforms developed for specific tracers ( 92 , 93 ) may inspire investigations of such analysis approaches for immune-metabolic tracers.…”

Targeting PSMA Revolutionizes the Role of Nuclear Medicine in Diagnosis and Treatment of Prostate Cancer

“…Recently, a deep learning algorithm (aPROMISE) has been developed for the automated analysis of PSMA PET images to provide a consistent and standardized evaluation. However, the results of the aPROMISE technology require further validation before it can be translated into clinical practice [ 73 ].…”