Prostate Cancer Screening With Abbreviated MRI Protocol

Overview

Prostate cancer is one of the most common malignancies in the male population with incidence and mortality rates comparable to breast cancer in women, but in contrast, a population screening program that would fulfill all the recommended criteria is not yet available. According to international recommendations, the preventive PSA sampling used in clinical practice is not suitable because of the concurrent detection of clinically insignificant carcinomas in a major proportion of tests. These clinically non-significant cancers make up a significant and increasing proportion with age. Detection of non-significant cancers burdens the health care system and patients with the care that has no positive impact on their health. Current preventive serum prostate-specific antigen (PSA) testing does not distinguish benign hyperplasia and nonsignificant carcinoma from clinically significant cancer. It is therefore not suitable for full-scale screening. According to current guidelines, magnetic resonance imaging (MRI) is indicated only in patients with an increased risk of cancer for detection or staging after biopsy and is not used for screening. According to recent studies, MRI has detected an increased proportion of significant cancers in the general population compared to screening based on PSA, while fewer clinically insignificant cancers have been detected. In screening, a shorter examination protocol without contrast medium (biparametric MRI) is used with a lower cost per examination, allowing to increase both the number of patients examined and patient comfort. The main objective of the project is to assess the contribution of imaging in the screening of clinically significant prostate cancer and to validate the published results in the Czech population, and extend the screening model by the second round of examinations and additional laboratory markers. The secondary aim is to design a subsequent study with a larger number of participants allowing statistical evaluation, similar to the successful breast cancer screening.

A prospective cross-sectional (with a longitudinal component, 2nd screening round) study evaluating the possibility of using the biparametric MRI protocol technique for screening clinically significant prostate cancer in men from the general population. Tests performed: * Serum PSA * PHI calculation (Prostate Health Index) to be performed only if the PSA values are in the range of 2-10 ng/l * MRI of the prostate (abbreviated biparametric protocol) * Digital rectal examination (DRE) as part of a clinical visit at a urologist in patients with a positive PSA test * Biopsy - if indicated MRI specifications: * Protocol with anatomical T2 sequence and diffusion-weighted images (DWI), according to the standards * Typical complete examination time does not exceed 20 minutes, planned acquisition time less than 15 minutes. * No contrast agent or spasmolytics is injected. Blinding: * Every test evaluator (radiologist/urologist) does not know the results of other tests. · MRI reports entered in the registry obligatorily before the biopsy. * The patient is not informed which test was positive and resulted in an indication for biopsy. * The pathologist does not know the results of MRI or laboratory tests. The sequence of tests: The MRI is assessed with the PI-RADS 2.1 system, each finding is reported on a scale of 1-5. To minimize the detection of non-significant cancers and to reduce the number of biopsies according to the results of the IP1-Prostagram study, a PI-RADS value of 4-5 was chosen as a positive test representation. Consensual double reading by 2 experienced uroradiologists (at least 400 MRI of the prostate read by the beginning of the study). Men with a positive MRI test are planned for a targeted MRI/US fusion and systematic prostate biopsy. Men with a positive blood marker (either PSA, PSAD, or PHI) are planned for a systematic 12 core biopsy. Positive test results are PSA ≥ 3, integrated marker PSAD ≥ 0.15, and PHI ≥ 35. Study participants are invited to repeat the screening tests after 2 years by letter. If they do not respond to a written offer, also by e-mail and SMS. Definition of clinically significant cancer: • ISUP Grade Group ≥ 2.