I really wouldn’t start worrying about that! Types of prostate cancer that don’t raise PSA are EXTREMELY rare. The common or garden variety of prostate cancer, adenocarcinoma, does raise PSA. The main reason for doing a biopsy is to check not only that you have cancer, but to identify what specific type of cancer cells are present. If the biopsy found only adenocarcinoma, it’s not going to spread without increasing PSA.
Best wishes,
Chris