PSMA-heterogeneity in metastatic castration-resistant prostate cancer: Circulating tumor cells, metastatic tumor burden, and response to targeted radioligand therapy
- PMID: 37147881
- DOI: 10.1002/pros.24549
PSMA-heterogeneity in metastatic castration-resistant prostate cancer: Circulating tumor cells, metastatic tumor burden, and response to targeted radioligand therapy
Abstract
Background: We explored the interrelation between prostate-specific membrane antigen (PSMA) expression on circulating tumor cells (CTCs) and that of solid metastatic lesions as determined by whole-body PSMA-targeted positron emission tomography (PET) to refine the prediction of response to subsequent PSMA-targeted radioligand therapy (RLT).
Methods: A prospective study was performed in 20 patients with advanced mCRPC. Of these, 16 underwent subsequent RLT with [177 Lu]Lu-PSMA-617 at a dose of 7.4 GBq every 6-8 weeks. PSMA expression on CTCs using the CellSearch system was compared to clinical and serological results, and to marker expression in targeted imaging and available histological sections of prostatectomy specimens (19% of RLT patients). Clinical outcome was obtained after two cycles of RLT.
Results: Marked heterogeneity of PSMA expression was observed already at first diagnosis in available histological specimens. Targeted whole-body imaging also showed heterogeneous inter- and intra-patient PSMA expression between metastases. Heterogeneity of CTC PSMA expression was partially paralleled by heterogeneity of whole-body tumor burden PSMA expression. Twenty percent of CTC samples showed no PSMA expression, despite unequivocal PSMA expression of solid metastases at PET. A high fraction of PSMA-negative CTCs emerged as the sole predictor of poor RLT response (odds ratio [OR]: 0.9379 [95% confidence interval, CI, 0.8558-0.9902]; p = 0.0160), and was prognostic for both shorter progression-free survival (OR: 1.236 [95% CI, 1.035-2.587]; p = 0.0043) and overall survival (OR: 1.056 [95% CI, 1.008-1.141]; p = 0.0182).
Conclusion: This proof-of-principle study suggests that liquid biopsy for CTC PSMA expression is complementary to PET for individual PSMA phenotyping of mCRPC.
Keywords: CellSearch; PSMA-617; circulating tumor cells; prostate-specific membrane antigen (PSMA); radioligand therapy.
© 2023 The Authors. The Prostate published by Wiley Periodicals LLC.
References
REFERENCES
-
- Siegel RL, Miller KD, Fuchs HE, Jemal A. Cancer statistics, 2022. CA Cancer J Clin. 2022;72:7-33.
-
- James ND, Spears MR, Clarke NW, et al. Survival with newly diagnosed metastatic prostate cancer in the “docetaxel era”: data from 917 patients in the control arm of the STAMPEDE trial (MRC PR08, CRUK/06/019). Eur Urol. 2015;67:1028-1038.
-
- Benešová M, Schäfer M, Bauder-Wüst U, et al. Preclinical evaluation of a tailor-made DOTA-conjugated PSMA inhibitor with optimized linker moiety for imaging and endoradiotherapy of prostate cancer. J Nucl Med. 2015;56:914-920.
-
- Schmuck S, Nordlohne S, von Klot CA, et al. Comparison of standard and delayed imaging to improve the detection rate of [(68)Ga]PSMA I&T PET/CT in patients with biochemical recurrence or prostate-specific antigen persistence after primary therapy for prostate cancer. Eur J Nucl Med Mol Imaging. 2017;44:960-968.
-
- Derlin T, Schmuck S, Juhl C, et al. PSA-stratified detection rates for [68Ga]THP-PSMA, a novel probe for rapid kit-based 68Ga-labeling and PET imaging, in patients with biochemical recurrence after primary therapy for prostate cancer. Eur J Nucl Med Mol Imaging. 2018;45:913-922.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Miscellaneous