This study seeks to analyse MRI images and biological samples from 60 men diagnosed as having intermediate risk prostate cancer at baseline and one year afterwards to compare the molecular, genetic and transcriptomic differences between cancers that progress and cancers which do not.

RECONCILE is a single centre, prospective, longitudinal observational cohort study. 60 consenting men with intermediate risk, gleason 3+4, prostate cancer under active surveillance will be recruited to the study. They will undergo blinded, concurrent molecular and radiological analysis of their cancer at baseline and at one year. Tests at baseline and one year will include mpMRI, targeted prostate biopsy and further tissue sampling (semen, urine and blood). There will be PSA monitoring at 3 monthly intervals throughout the study as per standard of care active surveillance. Tissue will be analysed for biological and molecular markers significantly associated with radiological progression events.

After consenting to taking part in the study a patient will come in for an MRI scan as standard of care. This scan will be used at a subsequent visit to inform a guided trans-perineal biopsy. At this biopsy visit patients will provide research blood samples, a urine sample and have a confirmatory biopsy. After the standard of care diagnostic tissue samples are taken, three research tissue samples will be taken.

If the patient has been identified through the ReIMAGINE study and consents to take part in RECONCILE then these baseline visits are not needed, the data from ReIMAGINE will be used as the baseline visit data.

The patient will come in as scheduled for their regular PSA visits in line with their active surveillance protocol. If a PSA test shows signs of potential progression the patient will have a standard of care diagnostic MRI, if this confirms progression then the imaging and biopsy visits scheduled for one year will be triggered early.

In the absence of any identified progression the patient will return after 12 months and have both the imaging and biopsy visits repeated (again providing blood and urine). After this visit the patient will be considered as having finished the study.

Patients who consent to take part in the study who have previously taken part in the PLiS semen donation study will be asked to provide a semen sample before the one year biopsy visit for comparison with the baseline sample that was provided for the PLiS study.

Inclusion Criteria:

• Male aged 18 years or above.
• Diagnosed with prostate cancer within 4 months of entry.
• Likert or PIRADS score greater than or equal to 4.
• PSA less than or equal to 15 ng.ml-1 in the last 6 months.
• mpMRI concordant with histology.
• Overall Gleason score 7 (3+4).
• Maximum cancer core length less than or equal to 10mm.
• Patients on active surveillance

Exclusion Criteria:

• Any contraindication to MRI scans (e.g. metal implants, unmanageable claustrophobia)
• Presence of a pacemaker
• Presence of a hip replacement
• Any hormonal treatment or inhibitors of 5 alpha-reductase in the previous 6 months
• Any previous TURP or other prostate surgery.
• Previous treatment for prostate cancer.
• Patients who have previously had sepsis due to a prostate biopsy
• Patients receiving concomitant treatment for their cancer
• Inability to provide full informed consent (e.g. due to dementia)

Participants must be men with prostate cancer

Men over the age of 18 with prostate cancer (Gleason 3+4) who are on active surveillance.

No individual participant data will be shared. Patients will be identified by a pseudo-anonymised patient number