Measuring response in metastatic castration-resistant prostate cancer using PSMA PET/CT: comparison of RECIST 1.1, aPCWG3, aPERCIST, PPP, and RECIP 1.0 criteria.

Abstract

PURPOSE:

To compare the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, the adapted Prostate Cancer Working Group Criteria 3 (aPCWG3), the adapted Positron Emission Tomography Response Criteria in Solid Tumors (aPERCIST), the PSMA PET Progression (PPP), and the Response Evaluation Criteria In PSMA-Imaging (RECIP) 1.0 for response evaluation using prostate-specific membrane antigen (PSMA)-PET/CT in men with metastatic castration-resistant prostate cancer (mCRPC) treated with 177Lu-PSMA radioligand therapy.

METHODS:

A total of 124 patients were included in this multicenter retrospective study. All patients received 177Lu-PSMA and underwent PSMA-PET/CT scans at baseline (bPET) and at 12 weeks (iPET). Imaging responses according to RECIST 1.1, aPCWG3, aPERCIST, PPP, and RECIP 1.0 were interpreted by consensus among three blinded readers. Changes in total tumor burden were obtained using the semi-automatic qPSMA software. The response according to each criterion was classified to progressive disease (PD) vs no-PD. Primary outcome measure was the prognostic value (by Cox regression analysis) for overall survival (OS). Secondary outcome measure was the inter-reader reliability (by Cohen's κ coefficient).

RESULTS:

A total of 43 (35%) of patients had non-measurable disease according to RECIST 1.1. Sixteen (13%), 66 (52%), 72 (58%), 69 (56%), and 39 (32%) of 124 patients had PD according to RECIST 1.1, aPCWG3, aPERCIST, PPP, and RECIP, respectively. PD vs no-PD had significantly higher risk of death according to aPCWG3 (HR = 2.37; 95%CI, 1.62-3.48; p < 0.001), aPERCIST (HR = 2.48; 95%CI, 1.68-3.66; p < 0.001), PPP (HR = 2.72; 95%CI, 1.85-4.01; p < 0.001), RECIP 1.0 (HR = 4.33; 95%CI, 2.80-6.70; p < 0.001), but not according to RECIST 1.1 (HR = 1.29; 95%CI, 0.73-2.27; p = 0.38). The κ index of RECIST 1.1, aPCWG3, aPERCIST 1.0, PPP, and RECIP 1.0 for identifying PD vs no-PD were 0.50 (95%CI, 0.32-0.76), 0.72 (95%CI, 0.63-0.82), 0.68 (95%CI, 0.63-0.73), 0.73 (95%CI, 0.63-0.83), and 0.83 (95%CI, 0.77-0.88), respectively.

CONCLUSION:

PSMA-PET-specific criteria for early response evaluation in men with mCRPC treated with 177Lu-PSMA achieved higher prognostic values and inter-reader reliabilities in comparison to conventional CT assessment or to criteria adapted to PSMA-PET from other imaging modalities. RECIP 1.0 identified the fewest patients with PD and achieved the highest risk of death for PD vs. no-PD, suggesting that other classification methods tend to overcall progression. Prospective validation of our findings on an independent patient cohort is warranted.

• Authors: Andrei Gafita, Isabel Rauscher, Wolfgang P Fendler, Vishnu Murthy, Wang Hui, Wesley R Armstrong, Ken Herrmann, Wolfgang A Weber, Jeremie Calais, Matthias Eiber, Manuel Weber, Matthias R Benz
• Journal: European journal of nuclear medicine and molecular imaging (Eur J Nucl Med Mol Imaging) Vol. 49 Issue 12 Pg. 4271-4281 (Oct 2022) ISSN: 1619-7089 [Electronic] Germany
• PMID: 35767071 (Publication Type: Journal Article, Multicenter Study)
• Copyright: © 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

Chemical References

• Dipeptides
• Heterocyclic Compounds, 1-Ring
• Lutetium
• Prostate-Specific Antigen

Topics

• Dipeptides (adverse effects)
• Heterocyclic Compounds, 1-Ring (adverse effects)
• Humans
• Lutetium
• Male
• Positron Emission Tomography Computed Tomography
• Positron-Emission Tomography
• Prostate-Specific Antigen
• Prostatic Neoplasms, Castration-Resistant (diagnostic imaging, radiotherapy)
• Reproducibility of Results
• Response Evaluation Criteria in Solid Tumors
• Retrospective Studies
• Tomography, X-Ray Computed
• Treatment Outcome