Hi, My Father Is 66 Years Old And Recently Had

Hi, my father is 66 years old and recently had a blood clot on the lung. He was treated for this & also referred to a urologist for tests. He has had a DRE & bloods & MRI. He has been for results today and been booked for a biopsy in 4 weeks time as there is a 'small suspicious area' shown on the scan. What could this be?