Prognostic Role of Free Psa Ratio at Biochemical Recurrence After Radical Treatments for Prostate Cancer (FPSAR)

Clalit Health Services

Status: Completed

Conditions: Death; Metastasis; Castration-resistant Prostate Cancer

Treatments: Diagnostic Test: Free PSA ratio test in patients after definitive treatment for localized prostate cancer

Study type: Observational

Funder types: Other

Identifiers

NCT03927287

17-5498

Details and patient eligibility

About

Measurement of Free PSA ratio in patients after definitive radical treatment for prostate cancer, and assessment of whether post-treatment free PSA ratio can function as a biomarker for advanced disease in prostate cancer patients.

Full description

Prostatic specific antigen (PSA) circulates mostly in complex with protease inhibitors, but 10-30% circulates as inactive free-PSA (FPSA). In patients with prostate cancer (PCa), pretreatment FPSA is lower and used to risk-stratify patients for biopsy. However, posttreatment FPSA ratio (FPSAR) is rarely quantified, with an unexplored clinical value.

Methods The institutional database was queried to identify patients following radical prostatectomy (RP cohort) or radiotherapy (RT cohort) between 2000 and 2017. For validation, the investigators identified an independent prospective cohort with biochemical recurrence (BCR) after RP, using biobank samples (biobank cohort). All patients had at least one posttreatment FPSAR test. Kaplan-Meier (KM) method was used to compare the metastasis-free (MFS), castration-resistant PCa (CRPC)-free, and cancer-specific-survival (CSS) rates. Multivariable Cox models determined the association between posttreatment FPSAR, metastases, and CRPC.

Enrollment: 822 patients

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

For the two retrospective cohorts:

1. All patients that older than 18 treated for localized adenocarcinoma of the prostate between 2000 and 2017 with either radical prostatectomy or radiotherapy
2. All treated patients had a rising post-treatment PSA, with at least one post-treatment free PSA blood test.

For the biobank validation cohort:

1. All patients treated with radical prostatectomy for localized prostate cancer between 2000 and 2017 who had biobank samples taken when developing biochemical recurrence.

Exclusion criteria

1. Patients that were younger than 18,
2. Patients with prostate cancer other than adenocarcinoma, such as small cell and neuroendocrine cancer
3. Patients with prostate adenocarcinoma that did not develop biochemical recurrence.
4. In the retrospective cohorts - patients that did not have at least one post-treatment free PSA blood test.

Trial design

822 participants in 3 patient groups

Radical prostatectomy (RP cohort)

Description:

Our institutional prostate cancer database was queried for all patients between 2000-2017 who had a biochemical recurrence (BCR) after radical prostatectomy (RP) (Total PSA\>=0.2 ng/ml) and had at least one post-BCR free PSA ratio (FPSAR) blood test (RP cohort). FPSAR ascertainments were performed incidentally or reflexively (e.g. PSA in the range of 4-10 ng/ml, as per Institutional policy). If multiple FPSAR tests were performed, only the first FPSAR test was analyzed. otal PSA and Free PSA data was performed with the Abbott Architect analytical platform, according to the instructions of the manufacturer.

Radiotherapy cohort

Description:

Our institutional database was queried or all patients between 2000-2017 who had a rising PSA after radiotherapy (RT) for intermediate- and high-risk prostate cancer, and at least one post-treatment free PSA ratio (FPSAR) blood test (RT cohort). As in the RP cohort, FPSAR was performed either incidentally or reflexively, and the first FPSAR test was used for the analyses. Total PSA and Free PSA data was performed with the Abbott Architect analytical platform, according to the instructions of the manufacturer.

Biobank surgical cohort

Description:

To validate our findings in the two retrospective cohorts (RP and RT), we analyzed a third cohort of prospectively collected biobank specimens of patients who underwent RP and developed biochemical recurrence(Biobank cohort). The retrieved samples were batched and tested for FPSAR levels to determine the results in lower PSA ranges and also to account for intrinsic analyte measurements variability in the retrospective cohorts. For his cohort we used the Roche Elecsys analytical platform, according to the instructions of the manufacturer.

Treatment:

Diagnostic Test: Free PSA ratio test in patients after definitive treatment for localized prostate cancer