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Immune Profiling After HDR in Local Relapsed Prostate Cancer

Prostate Cancer Immune Profiling Before, During and After HDR-brachytherapy in Local Relapsed Prostate Cancer (PRIMUS-study)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04247217
Acronym
PRIMUS
Enrollment
10
Registered
2020-01-29
Start date
2020-02-19
Completion date
2021-12-23
Last updated
2022-05-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

PD-L1, Prostate Cancer

Brief summary

Immunotherapy is currently revolutionizing the field in oncology. However, prostate cancer until now fails to respond to classical IO, like PD-1 and CTLA-4 inhibitors. Radiotherapy (RT) delivered to the primary tumor impacts both tumor cells and surrounding stromal cells. Radiation damage to cancer cells exposes tumor-specific antigens leading to increased visibility to the immune system by improved priming and activation of cytotoxic T cells. RT-induced modulation of the tumor microenvironment may also facilitate the recruitment and infiltration of immune cells by increasing the expression or T-cell attracting chemokines and by increasing T-cell docking molecules on the endothelial cells like VCAM-1. The main-hypothesis is that HDR-brachytherapy will turn an immunologically cold (no T-cell infiltrations) prostate cancer into an immunologically hot (CD4 and CD8-cell infiltrations) tumor, creating leverage points for different forms of IO.

Detailed description

Prospective analysis of biopsies from 10 patients with local recurrence in the prostate selected for salvage HDR brachytherapy in MAASTRO Clinic, Maastricht. HDR treatment is standard in Maastro Clinic for local relapses of prostate cancer after previously irradiation (internal or external). Biopsies will be taken at 4 different time points (before and after the 1st fraction; before the 2nd and 3rd fraction of the salvage treatment). Several immunotyping (expression of PD-(L)-1, CXCL12, IL-23 receptor, etc.) and HLA class I expression will be performed on the biopsies. In addition, HLA genotypes will be determined on DNA isolated from pheripheral blood. The plasma and the biopsies will be stored for eventually additional research.

Interventions

RADIATIONHDR salvage brachytherapy

In patients receiving HDR salvage brachytherapy for locally relapsed prostate cancer serial biopsies will be performed at 4 different time points.

Sponsors

Maastricht Radiation Oncology
Lead SponsorOTHER

Study design

Observational model
CASE_ONLY
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum

Inclusion criteria

* Local relapse of prostate cancer, who is candidate for a salvage HDR treatment: * Biochemical relapse (PSA increase) * Local relapse on imaging: PSMA scan, mp-MRI * Pathology proven relapse * Willing and able to comply with the study prescriptions. * 18 years or older * Before patient registration, written informed consent must be given according to ICH/GCP, and national/local regulations.

Exclusion criteria

* Not eligible for proposed (HDR brachytherapy) treatment: * Life expectancy \< 10 years * Distant Metastasis * Recently TURP with big urethral defect * Not able to stop anticoagulants * Flow \< 10 ml/sec • No compliance to study procedure

Design outcomes

Primary

MeasureTime frameDescription
Expression of PD-(L)-1 receptorup to 28 daysExpression of PD-(L)-1 receptor induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points.

Secondary

MeasureTime frameDescription
Expression patterns of CXCL12up to 28 daysExpression of CXCL12 receptor induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Expression patterns of IL-23up to 28 daysExpression of IL-23 receptor induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Expression patterns of MDSCup to 28 daysExpression of MDSC receptor induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Changes in HLA class I-A expression on tumor cellsup to 28 daysChanges in HLA class I-A expression on tumor cells induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Changes in HLA class I-B expression on tumor cellsup to 28 daysChanges in HLA class I-B expression on tumor cells induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Changes in HLA class I-C expression on tumor cellsup to 28 daysChanges in HLA class I-C expression on tumor cells induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points
Changes in T cell infiltration profilesup to 28 daysChanges in T cell infiltration profiles induced by HDR-brachytherapy in prostate tumor biopsies of local relapses of prostate cancer of 10 patients at 4 different time points

Countries

Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026