PSMA-RADS 2.0: clinical validation and technical considerations for prostate-specific membrane antigen positron emission tomography/computed tomography image interpretation.

BACKGROUND

The updated diagnostic framework prostate-specific membrane antigen Reporting and Data System 2.0 (PSMA-RADS 2.0) has been introduced as a standardized scoring system for PSMA positron emission tomography/computed tomography (PET/CT) structured reporting to enhance the accuracy and clinical utility of prostate cancer (PCa) lesion interpretation. This study aims to evaluate the reliability and identify potential limitations of PSMA-RADS 2.0 in clinical applications.

METHODS

We conducted a comparative analysis between PSMA-RADS versions 1.0 and 2.0, followed by prospective evaluation of 109 lesions using PSMA-RADS 2.0 criteria. Inter- and intra-reader consistencies were analyzed statistically to evaluate the reliability and practicality of the scoring system. In the context of two independent readings, the inter-reader consistency between experienced readers (ERs) and inexperienced readers (IRs) was evaluated using the intra-class correlation coefficient (ICC).

RESULTS

Compared to version 1.0, PSMA-RADS 2.0 simplified primary PSMA-RADS-1 classification for Category I lesions and introduced PSMA-RADS-5T for post-treatment assessment. Inter-reader correlation coefficients values demonstrated excellent consistency (ERs: 0.964-0.969; IRs: 0.929-0.932). Intra-reader correlation coefficients ranged from 0.920 to 0.985 across all readers. However, challenges persisted in lymph node interpretation (ICC: 0.797-0.823) and post-treatment classification.

CONCLUSIONS

PSMA-RADS 2.0 provides a reliable framework for PSMA PET/CT interpretation, even for IRs. Further refinement is needed for post-treatment categorization and lymph node differentiation. The proposed PSMA-RADS-5T sub-classification complete remission/partial remission/stability disease/progression disease (CR/PR/SD/PD) may enhance clinical utility for treatment monitoring.