Dataset Information

Pilot Study: PARP1 Imaging in Advanced Prostate Cancer.

ABSTRACT:

Purpose

PARP inhibitor (PARPi) therapy is approved for patients with metastatic castration-resistant prostate cancer (mCRPC) and homologous recombination repair (HRR) genomic aberrations. However, only a fraction of patients with BRCA1/2 mutations respond to PARPi therapy. In this pilot study, we assess PARP-1 expression in prostate cancer patients with and without HRR genomic alternations using a novel PARP-based imaging agent.

Procedures

Nine advanced prostate cancer patients were studied with PET/CT and [¹⁸F]FluorThanatrace (FTT), an analogue of the PARPi rucaparib. Images were analyzed using maximum standardized uptake values (SUV_max). PARP expression was assessed by immunohistochemistry (IHC) when feasible (n = 4).

Results

We found great variability in FTT uptake (SUV_max range: 2.3-15.4). Patients with HRR mutations had a significantly higher SUV_max (p = 0.0379) than patients with non-HRR mutations although there was an overlap in FTT uptake between groups. Three patients without HRR and one with HRR mutations had similarly high PARP1 IHC expression.

Conclusions

FTT-PET/CT may serve as an alternate biomarker for PARP1 expression and a potential method for PARPi treatment selection.

SUBMITTER: Dehdashti F

PROVIDER: S-EPMC9681698 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Publications

Pilot Study: PARP1 Imaging in Advanced Prostate Cancer.

Dehdashti Farrokh F Reimers Melissa A MA Shoghi Kooresh I KI Chen Delphine L DL Luo Jingqin J Rogers Buck B Pachynski Russell K RK Sreekumar Sreeja S Weimholt Cody C Zhou Dong D

Molecular imaging and biology 20220614 6

<h4>Purpose</h4>PARP inhibitor (PARPi) therapy is approved for patients with metastatic castration-resistant prostate cancer (mCRPC) and homologous recombination repair (HRR) genomic aberrations. However, only a fraction of patients with BRCA1/2 mutations respond to PARPi therapy. In this pilot study, we assess PARP-1 expression in prostate cancer patients with and without HRR genomic alternations using a novel PARP-based imaging agent.<h4>Procedures</h4>Nine advanced prostate cancer patients we ...[more]

PMID: 35701722

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Dataset Information

Pilot Study: PARP1 Imaging in Advanced Prostate Cancer.

Purpose

Procedures

Results

Conclusions

Publications

Pilot Study: PARP1 Imaging in Advanced Prostate Cancer.

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