Prostate Cancer Biobank

Overview

Carcinoma of the prostate is the second most commonly diagnosed cancer and occurs predominantly in older men - almost two-thirds of those affected are over 65 years of age. In a significant proportion of patients, the disease is harmless and progresses only very slowly. As a result, there is a risk of overdiagnosis and overtreatment. The main diagnostic tool for prostate cancer is the prostate-specific antigen (PSA) test, but its specificity is minimal. It is important to look for other biological characteristics (biomarkers) that provide pointers to the need for a diagnosis and treatment. Even after treatment and in advanced stages of disease, decisions are often difficult, because it is not necessarily clear which patient needs a specific treatment. In this study, a multicenter biobank of patient sera, plasma and tissue is being established together with information of relevance to the disease, in order to provide a basis for the testing of biomarkers. The aim is to identify markers that offer diagnostic and treatment-selective pointers and thus make a decisive contribution to the optimum care of patients.

Background \& Rationale: Prostate Cancer (PCa) occurs mainly in older men, nearly two thirds are diagnosed in men aged 65 or older. However, in a substantial subset of patients, the disease will be slow-growing and harmless. This highlights one of the major issues with PCa screening and diagnosis: the risks of over-detection and overtreatment, i.e. to diagnose and invasively treat indolent cancers that may lead to reduced quality of life without increasing overall survival. The main diagnostic tool for PCa is the systematic screening for PSA (prostate-specific antigen), despite the low specificity of PSA and the unclear cut-off value, resulting in a large proportion of unnecessary biopsies with potential side effects. Additionally, as screening addresses a healthy population and screened men may suffer from disadvantages, such as unnecessary biopsies, screening in PCa remains controversial. Besides the dilemmas in PCa screening, there are several additional important clinical questions that deserve further investigation and better risk-adapted patient stratification as follows: 1) active treatment versus deferred therapy in the heterogeneous group of patients with localized PCa; 2) treatment intensification for locally-advanced, high-risk prostate cancers with significant risk of PCa-related deaths; 3) optimal approach for patients with high risk of local recurrence post-radical prostatectomy; 4) treatment of patients with rising PSA (biochemical relapse) after curative treatment (either radical prostatectomy or RT); 5) a better understanding of oligometastatic disease and; and 6) treatment of patients with castration-resistant prostate cancer (CRPC). PCa is characterized by a wide spectrum of molecular and phenotypic characteristics. PCa patients are currently grouped in different risk categories, illustrating particular features of a heterogeneous disease. On one side, many patients present benign disease, such as benign prostate enlargement caused by prostate hyperplasia and, on the other side, progressively malignant PCa, ranging from localized, locally-advanced, metastatic and castrate-resistant disease. For the purpose of this study, we established 5 groups and their corresponding subgroups, as follows: A) Opportunistic screening and benign prostate syndrome (BPS) with prostate biopsy; B) Localized and locally advanced prostate cancers treated with curative intent; C) Biochemical relapse after RP; D) Metastatic advanced PCa without curative treatment but hormone sensitive disease, treated with ADT (medical or surgical); E) Metastatic castration resistant prostate cancer (mCRPC). Currently a comprehensive biobank in the field of urogenital disease, driven by a multidisciplinary panel (composed by specialists from the following fields: urology, medical oncology, radio-oncology and pathology), does not exist in Switzerland. Such biobank (together with the corresponding clinical data) would enable researchers and clinicians alike to discover and validate diagnostic, prognostic and predictive PCa biomarkers, which are currently highly needed. Importantly, the biobank shall consist of specific sample sets related to the different stages of PCa development (including screened healthy men and newly diagnosed patients). Ultimately, this comprehensive project will allow addressing some of the urgent questions in different stages of PCa. Objective: To create a novel and comprehensive plasma and serum biobank of about 55000 samples (derived from about 1540 patients) accompanied by the corresponding clinical data. This will enable us to explore and validate different diagnostic, prognostic and predictive biomarkers regarding prostate disease.