Multiparametric MRI of the prostate is recommended before each prostate biopsy. It identifies suspicious areas which will then be the subject of targeted biopsies. However, MRI suffers from low specificity and moderate inter-reader reproducibility, including with the use of the PI-RADS version 2.1 score.

We are developing, within the framework of RHU PERFUSE, a computer-aided diagnosis system (CAD) for the detection of ISUP ≥2 cancers. This system has been trained on a database of patients who had prostate MRI and prostatectomy at the Hospices Civils de Lyon and performed well on a database of patients who had prostate MRI before biopsy at the Hopices civils de Lyon.

However, one of the weaknesses of artificial intelligence systems is their low robustness when tested on MRI images from different manufacturers or institutions.

The goal of the CHANGE study is to build a prospective multicenter cohort of patients who underwent prostate multiparametric MRI followed by systematic and targeted prostate biopsies. The cohort will be used for the final external validation of the CAD developed in PERFUSE.

Inclusion Criteria:

• Men over 18 years of age
• Patient with clinical suspicion of prostate cancer referred for a multiparametric MRI of the prostate before a first series of biopsies or before new biopsies after one or more series of negative biopsies
• PSA ≤ 30 ng / ml
• Clinical stage ≤ T2c
• Affiliation or beneficiary of a social security scheme

Exclusion Criteria:

• Men over 80 years of age
• PSA> 30 ng / ml
• Stage T3 or T4 on digital rectal examination
• Previous prostate biopsy performed within 12 months
• History of prostate cancer diagnosed by biopsy or endourethral resection.
• History of pelvic radiotherapy regardless of the cause.
• History of total or focal treatment for prostate cancer.
• History of hormone therapy
• MRI performed more than 3 months before biopsy
• Prostate MRI performed on a machine other than the center's machines accredited for the study.
• Presence of a hip prosthesis
• Contraindication to performing an MRI
• Contraindication to performing prostate biopsy
• Patient subject to a legal protection measure or deprived of liberty
• Subject participating or having participated in interventional medical research with an exclusion period still in progress
• Misunderstanding of the French language

After publication of the results of the trial, the CHANGE cohort will be made partially accessible to other investigators wishing to test a CAD system aimed at detecting/localizing prostate cancer on MR images while respecting patient information. Request for access to pseudonymized data will be reviewed by the Trial Steering Committee that will grant access or not. To gain access, requestors will be required to sign a data access agreement. Of note, investigators will have access only to the MR images and not to the histological findings. After analysis of the CHANGE MR images by their CAD system, the investigator will be requested to send the results to the Hospices Civils de Lyon. The comparison between the CAD findings and the targeted and systematic biopsy findings will be made by the Hospices Civils de Lyon that will then inform the investigator of the CAD diagnostic performance.