Dataset Information

Positron Emission Tomography/Computed Tomography with Gallium-68-labeled Prostate-specific Membrane Antigen Detects Relapse After Vascular-targeted Photodynamic Therapy in a Prostate Cancer Model.

ABSTRACT:

Background

Evaluating the efficacy of focal therapy for prostate cancer is limited by current approaches and may be improved with biological imaging techniques.

Objective

We assessed whether positron emission tomography/computed tomography with gallium-68-labeled prostate-specific membrane antigen (⁶⁸Ga-PSMA PET/CT) can be used to predict relapse after vascular-targeted photodynamic therapy (VTP).

Design, setting, and participants

A total of 1×10⁶ LNCaP cells were grafted subcutaneously in the flanks of 6-8-wk-old SCID mice. Of 24 mice with measurable tumors 6 wk after tumor implantation, 20 were treated with VTP (150mW/cm²) to ablate the tumors. Blood prostate-specific antigen (PSA) levels were assessed, and ⁶⁸Ga-PSMA PET/CT images were performed 1 d before VTP and 1 and 4 wk after.

Outcome measurements and statistical analysis

Local tumor relapse was evaluated by histology, and tumors were analyzed by prostate-specific membrane antigen (PSMA) and PSA immunohistochemistry. T tests and Kruskal-Wallis tests were used to determine significance.

Results and limitations

Four weeks after VTP, 11 (65%) mice had complete responses and six (35%) had tumor relapses confirmed by histology (hematoxylin and eosin, and PSMA immunohistochemistry). All mice with local relapse had positive ⁶⁸Ga-PSMA PET/CT findings 4 wk after VTP; all complete responders did not. One week after VTP, the relapse detection sensitivity of ⁶⁸Ga-PSMA PET/CT was 75%, whereas the sensitivity of PSA was only 33%. Compared with controls, relapsed tumors had a three-fold reduction in the number of cells with strong PSA staining by immunohistochemistry (1.5% vs 4.5%; p=0.01).

Conclusions

In a preclinical prostate cancer model, we show that ⁶⁸Ga-PSMA PET/CT can identify and predict relapse earlier than blood PSA level. These findings support further testing in clinical trials.

Patient summary

Positron emission tomography/computed tomography with gallium-68-labeled prostate-specific membrane antigen may be used to follow and evaluate treatment outcomes in men who receive focal therapy for prostate cancer.

SUBMITTER: Alvim R

PROVIDER: S-EPMC7032651 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Publications

Positron Emission Tomography/Computed Tomography with Gallium-68-labeled Prostate-specific Membrane Antigen Detects Relapse After Vascular-targeted Photodynamic Therapy in a Prostate Cancer Model.

Alvim Ricardo R Nagar Karan K Das Sudeep S Lebdai Souhil S Wong Nathan N Somma Alexander A Hughes Christopher C Thomas Jasmine J Monette Sébastien S Scherz Avigdor A Kim Kwanghee K Grimm Jan J Coleman Jonathan A JA

European urology focus 20190618 2

<h4>Background</h4>Evaluating the efficacy of focal therapy for prostate cancer is limited by current approaches and may be improved with biological imaging techniques.<h4>Objective</h4>We assessed whether positron emission tomography/computed tomography with gallium-68-labeled prostate-specific membrane antigen (<sup>68</sup>Ga-PSMA PET/CT) can be used to predict relapse after vascular-targeted photodynamic therapy (VTP).<h4>Design, setting, and participants</h4>A total of 1×10<sup>6</sup> LNCa ...[more]

PMID: 31227464

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Dataset Information

Positron Emission Tomography/Computed Tomography with Gallium-68-labeled Prostate-specific Membrane Antigen Detects Relapse After Vascular-targeted Photodynamic Therapy in a Prostate Cancer Model.

Background

Objective

Design, setting, and participants

Outcome measurements and statistical analysis

Results and limitations

Conclusions

Patient summary

Publications

Positron Emission Tomography/Computed Tomography with Gallium-68-labeled Prostate-specific Membrane Antigen Detects Relapse After Vascular-targeted Photodynamic Therapy in a Prostate Cancer Model.

Similar Datasets

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