Hi Callanish.
I'm sorry that you've had to join us but welcome to the forum, mate.
The PI-RAD 4 means that it seems likely the lesion is cancerous, however, only a biopsy will confirm or negate that. We have had cases where PI-RAD 4 and 5's have turned out to be inflammation or benign lesions.
Do you know whether your prostate is enlarged, because that itself can elevate your PSA, as can other non cancerous prostate conditions.
Best of luck with your biopsy results. Please keep us updated.👍