A multi-site study to evaluate the potential use of the ChEC test of seminal fluid as an additional triage test in stratifying patients for further tests.

A biomarker is a molecular substance that is an indicator of a biological condition. Cambridge Oncometrix believe that a semen biomarker may be able to predict the presence of prostate cancer. This study will allow work to be carried out on semen samples donated by men who have been identified by their GPs as having a risk of prostate cancer. Normally, GPs refer men with symptoms or a raised PSA to hospital to have an MRI scan and a biopsy.

The PLiS research team at the hospital will contact potential patients, who have been referred by their GPs, before they have an MRI or a biopsy, ask them if they are willing to take part in the study, consent them and ask them to provide a semen sample. Semen samples will be produced by the potential participants at home into a seminal fluid collection container, they will also have to complete a study questionnaire. Both the sample and the questionnaire will be returned to the central laboratory in Cambridge using the stamped addressed envelope provided.

In addition to providing a semen sample and completing a questionnaire, each participant will have two blood tests to measure male hormones. Participants then exit the trial and their usual care carries on from this point. The PLiS study will register 400 men and of those it is hoped that 300 of them will be able to provide semen.

Inclusion Criteria:

1. - Men over 40 years old with suspected prostate cancer who have been referred to a secondary care
2. - Men able to produce a semen sample
3. - Men able to have a prostate mpMRI
4. - Men who have given their written informed consent

Exclusion Criteria:

1. - Previous history of prostate biopsy
2. - Contraindication to MRI
3. - Previous history of prostate surgery
4. - Treatment with 5-alpha-reductase inhibitors at time of registration or during the prior 6 months
5. - Evidence of urinary tract infection or history of acute prostatitis within the last month
6. - Androgen replacement therapy within the last 3 months
7. - Any other medical condition precluding standard diagnostic workup and collection of semen samples.

Men over the age of 40 who have been referred for secondary care due to suspicion of prostate cancer who are able to have an MRI scan and produce a semen sample.