“Halt! Who goes there?” The world of Hollywood is filled with movies in which an alert sentry confronts a sneaky intruder. No matter which era is depicted—the Middle Ages, the Wild West, World War II—the watchful guardians are spaced out at various points along a castle parapet, a fort’s watch towers, or a defensive line. When alerted by the approach of a potential enemy, the sentry musters a commanding voice and speaks the four famous words (or a close equivalent). We all know the script: If it looks like a threat, the intruder is brought in for further questioning.

For prostate cancer (PCa) patients on Active Surveillance (AS), there is a monitoring protocol to keep an eye on the tumor. “Sentries” in the form of PSA tests, digital rectal exams (DRE), MRI scans, and repeat biopsies are posted. Instead of geographic positions along a wall, however, they are spaced at intervals of time rather than geography. If the PSA comes back high, or a lump is felt during a DRE, or a suspicious area shows up on imaging, it’s like a halt-who-goes there signal that PCa activity may be intruding. Since this definitely could be a threat, the next step is further questioning in the form of a needle biopsy even if one was not yet scheduled. Patients understand and accept it when suspicious activity triggers a biopsy, because the don’t want to miss a treatment window.

Monitoring protocol and routine repeat biopsy

Most AS protocols are in alignment regarding the frequency of PSA tests and DREs. An annual multiparametric MRI (mpMRI) is increasingly a standard of care. However, there is a lack of agreement about when and how often to conduct a monitoring biopsy. Many doctors feel that even if PSA is stable, DRE is normal, and MRI is negative for suspicious change, a protocol biopsy should be done every year, or every two years after the first 1-year biopsy—even if the previous biopsy was negative for change.

Patients on AS are starting to question the necessity for protocol biopsies, in favor of suspicion triggered biopsies. They don’t like the idea of being over-biopsied, due to the potential side effects, especially pain, infection, bleeding, and sexual dysfunction. They don’t like having to be on an antibiotic for every biopsy. We believe these are legitimate concerns, because there is a save and noninvasive way to know if the protocol biopsy can be avoided. It’s the use of mpMRI to evaluate whether a protocol biopsy is really necessary.

An April, 2022 paper by multinational European team reported on an analysis of 1185 AS patients who had had 1488 MRI-informed biopsies among them.^[i] Upon reviewing all clinical records, including mpMRI scans, the authors determined that it was possible to predict (prior to a protocol biopsy) probably tumor upgrading based on a patient’s age, MRI results using PI-RADS scoring, PSA density, and the percentage of positive cores of the last systematic biopsy (12+ needles). They concluded that patients with negative MRI and PSA density <0.15 ng/ml could safely have a protocol-based biopsy omitted. However, a confirmatory biopsy “cannot simply be omitted in all patients diagnosed with upfront MRI” as other variables must be taken into account. The importance of incorporating mpMRI into AS monitoring can’t be overstated. In addition to helping avoid subjecting patients to over-biopsy, the tracking of PSA (and its variants) and mpMRI results over the period of surveillance is essential for treatment planning when the time comes to convert to active treatment. At the Sperling Prostate Center, we have a high degree of confidence in our mpMRI services for PCa patients on AS. In addition to our powerful magnet and experienced team, we also employ Artificial Intelligence tools to enhance the accuracy of our imaging results. We believe it’s always in the patient’s best interest to obtain the best possible imaging as an aid to biopsy decisions. And, if a biopsy proves necessary, our in-bore MRI-guided targeted biopsy is a leader in diagnostic accuracy. If you or a loved on is on AS, contact us for a consultation on how we can assist you.

NOTE: This content is solely for purposes of information and does not substitute for diagnostic or medical advice. Talk to your doctor if you are experiencing pelvic pain, or have any other health concerns or questions of a personal medical nature.

[i] Luiting HB, Remmers S, Boevé ER, Valdagni R et al.. A Multivariable Approach Using Magnetic Resonance Imaging to Avoid a Protocol-based Prostate Biopsy in Men on Active Surveillance for Prostate Cancer-Data from the International Multicenter Prospective PRIAS Study. Eur Urol Oncol. 2022 Apr 15:S2588-9311(22)00057-8.