The biopsy characteristics of the cancers detected in 17 men with a positive screening MRI and a PSA <3 ng/mL included 2 Gleason 3+3 cancers, 13 Gleason 3+4 cancers, with a mean cancer core length (MCCL) of 7 mm, 1 Gleason 4+3 (3mm MCCL) and 1 Gleason 4+5 (9mm MCCL) (online supplemental table A4). This evidence concerns the gene KLK3 and cancer.