PSA After Rezum Procedure: Post-Treatment Changes to Expect

Prostate-specific antigen (PSA) levels are a key marker of prostate health, and many patients wonder what to expect after undergoing the Rezum procedure. This minimally invasive water vapor therapy reduces prostate tissue and improves urinary symptoms, but it also affects PSA levels differently than other treatments. Understanding these changes helps set expectations and guide follow-up care.

Prostate Changes Following Water Vapour Therapy

The Rezum procedure triggers structural and physiological changes in the prostate as treated tissue undergoes necrosis and is gradually resorbed. Sterile water vapor disperses through targeted prostate regions, causing cellular disruption and apoptosis. Over the following weeks, the body’s inflammatory response breaks down and clears the ablated tissue, reducing prostate volume. Clinical studies show that prostate size decreases by about 28% within six months, with the most significant shrinkage in the first three months (McVary et al., 2018, Journal of Urology).

As the prostate contracts, pressure on the urethra diminishes, relieving lower urinary tract symptoms (LUTS) like weak stream, urgency, and nocturia. Unlike mechanical interventions such as stents or resection, Rezum relies on the body’s natural ability to clear necrotic tissue and remodel the prostate. The degree of improvement varies based on initial prostate size and the extent of tissue ablation, but most patients experience a meaningful reduction in International Prostate Symptom Score (IPSS) within months.

The destruction of hyperplastic tissue reduces epithelial cells that contribute to PSA production, leading to a decline in serum PSA levels over time. However, the initial phase of tissue breakdown and inflammation may temporarily elevate PSA before a downward trend begins. This transient increase is common with thermal ablation techniques and typically resolves as inflammation subsides.

PSA Patterns After The Procedure

PSA levels follow a distinct trajectory after the Rezum procedure. In the first few weeks, PSA often rises temporarily due to inflammation and cellular breakdown from thermal energy. Some patients experience increases of up to 50% from baseline before stabilization. This fluctuation usually peaks within a month and gradually declines as necrotic tissue clears (McVary et al., 2018, Journal of Urology).

As inflammation resolves, PSA levels drop, reflecting reduced prostate tissue. By three months, most patients see a decline of 25% to 40%, depending on initial gland size and the extent of tissue destruction. This trend continues over the following months, with many reaching a new baseline by six to twelve months post-procedure. The magnitude of this decrease generally aligns with prostate shrinkage (Elterman et al., 2021, Canadian Urological Association Journal).

Unlike radical prostatectomy or radiation therapy, which drastically lower PSA, Rezum preserves part of the prostate, so PSA does not drop to near-zero levels. Instead, it stabilizes at a lower level than before treatment. Sustained PSA reduction typically lasts for years, though periodic monitoring is necessary to detect any unexpected rises that may indicate residual gland hypertrophy or other changes.

Variables That Affect PSA Levels

PSA levels fluctuate due to various physiological and clinical factors. One major influence is baseline prostate volume, as larger glands naturally produce more PSA. While Rezum reduces gland size, the extent of PSA decline depends on how much tissue is ablated. This explains why two patients with similar pre-procedure PSA levels may experience different post-treatment trajectories.

Age also plays a role, as PSA levels tend to rise with age due to increased epithelial cell turnover and subclinical prostatic changes. Older patients may see a slower PSA decline than younger individuals, partly due to chronic inflammation or low-grade hyperplasia that persists post-treatment. Hormonal factors, particularly testosterone levels, also impact PSA. Men on testosterone replacement therapy (TRT) may see slight PSA elevations, while those with declining testosterone may experience a more pronounced drop.

Pre-existing prostate conditions further affect PSA trends. Chronic prostatitis or prior interventions can cause intermittent PSA spikes unrelated to BPH, complicating post-Rezum monitoring. Additionally, past biopsies or other treatments may leave residual scarring or altered vascularization, influencing PSA stability. Medications like 5-alpha reductase inhibitors (e.g., finasteride, dutasteride) lower PSA by about 50%, meaning patients on these drugs before Rezum may have artificially suppressed pre-treatment levels. Discontinuing or continuing these medications post-procedure can significantly alter PSA trends.

Laboratory Testing Considerations

Accurate PSA monitoring after Rezum requires consistency in testing protocols. Blood samples should be drawn under the same conditions each time, ideally at the same time of day, avoiding recent activities that could temporarily elevate PSA. Ejaculation, vigorous exercise, or a digital rectal exam (DRE) within 48 hours before testing can cause fluctuations, so following pre-test guidelines is essential for reliable comparisons.

Different labs may use slightly varied PSA testing methodologies, leading to discrepancies. Patients should ideally have their PSA tested at the same laboratory to minimize variability. Clinicians may also assess PSA velocity—the rate of change over time—rather than relying solely on absolute values, as this provides a clearer picture of post-treatment trends.