It’s possible that he didn’t have regular PSA years. Current USPSTF guidelines recommend against PSA screening after age 70 (https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/prostate-cancer-screening). So, it would be interesting to know if his doctors strictly followed current USPSTF guidelines. Did he even have a PSA screening test last year (or even the past decade) as part of his annual health exams?