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

Completed

• Conditions: Metastasis; Death; Castration-resistant Prostate Cancer
• Interventions: Diagnostic Test: Free PSA ratio test in patients after definitive treatment for localized prostate cancer

• Registration Number: NCT03927287
• Lead Sponsor: Rabin Medical Center

Brief Summary

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.

Detailed 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.

Study Timeline

• Study Start: 2018-01-01
• Primary Completion: 2018-12-30
• Status Verified: 2019-04
• Study Completion: 2019-04-10
• Study First Submitted: 2019-04-19
• Study First Submitted QC: 2019-04-22
• Last Update Submitted: 2019-04-22
• Study First Posted: 2019-04-25
• Last Update Posted: 2019-04-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 822

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.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Biobank surgical cohort	Free PSA ratio test in patients after definitive treatment for localized prostate cancer	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.

Primary Outcome Measures

Name	Time	Method
Metastasis free survival	From date of diagnosis to date of Metastasis development, assessed up to 200 months	Rate of Metastasis correlated to the first post-treatment free PSA ratio

Secondary Outcome Measures

Name	Time	Method
Cancer specific survival	From date of diagnosis to date of cancer specific death, assessed up to 200 months	Rate of Cancer specific survival correlated to the first post-treatment free PSA ratio
Castrate resistant prostate cancer (CRPC) free survival	From date of Diagnosis to date of CRPC development, assessed up to 200 months	Rate of CRPC correlated to the first post-treatment free PSA ratio

Trial Locations

Locations (1)

Princess Margaret Cancer Center; 🇨🇦 Toronto, Ontario, Canada