A Smarter Way to Screen for Prostate Cancer, With Isaac Kim, M.D., Ph.D.

Isaac Kim, M.D., Ph.D., MBA, chair of urology at Yale School of Medicine, explains the role of prostate-specific antigen (PSA) testing in prostate cancer screening. PSA is a protein made by the prostate, important in fertility but not cancer-specific. Despite this, PSA testing remains the best available screening tool due to its simplicity, validation across multiple studies and decades of clinical experience.

Kim recommends men establish a baseline PSA at age 40, then tailor follow-up intervals based on results:

• PSA <1: next test at age 50
• PSA 1-2: retest in 5 years
• PSA >2: retest every 23 years

Men at higher risk — those with a family history or Black men, who face higher incidence and worse outcomes — should be especially proactive. While age 40 is generally reasonable, rare cases of prostate cancer in younger men highlight that there is no one-size-fits-all rule.

Because PSA levels can fluctuate significantly, Kim advises confirming abnormal results with a repeat test before further steps. If confirmed, the next diagnostic phase involves MRI and prostate biopsy. He recommends combining targeted and systematic biopsies because MRI interpretation quality varies widely among radiologists.

Kim also outlines the history of PSA screening guidelines. In 2012, the U.S. Preventive Services Task Force advised against routine screening over concerns about overtreatment and side effects (incontinence, sexual dysfunction). This led to rising mortality rates, prompting a revision to cautiously support screening. Today, the approach is more individualized, with some men undergoing active surveillance instead of immediate treatment, and newer options like focal therapy emerging.

He stresses that although some prostate cancers progress slowly, advanced disease — when spread to bones or lymph nodes — can be just as deadly as other cancers, with a five-year survival rate of metastatic prostate cancer around 40%. Given PSA’s effectiveness, no one should present with advanced disease simply because they weren’t screened. The modern approach balances early detection with treatment decisions based on cancer risk, making outdated the belief that screening inevitably leads to harmful overtreatment.