What is the purpose of focal therapy?

“Focal therapy aims to eliminate cancerous cells while preserving the surrounding healthy tissue and by minimizing the side effects and functional disorders.”^[i] This 2025 quote from a paper in the journal Nature sums up focal therapy very nicely. I want to emphasize these three points:

1. Eliminate prostate cancer
2. Spare healthy tissue
3. Minimize risk of treatment side effects.

Focal therapy is accomplished by minimal to noninvasive ablation (destruction) of the tumor within the prostate gland. There is no surgery or radiation, so focal therapy is often called focal ablation. The Sperling Prostate Center provides expert MRI-guided focal ablation for localized prostate cancer.

Who is a candidate for focal therapy?

Focal therapy is appropriate for patients with low- to favorable intermediate-risk prostate cancer who have an index lesion (primary lesion) confined to a specific area. Thanks to multiparametric MRI (mpMRI), we are able to identify the location and size of such lesions.

Next, we define the risk level by taking biopsy samples targeted directly into the lesion. This gives us the most accurate diagnosis of the cancer that is growing there. We also take into account tangible clinical factors: patient age, PSA, current health status, appropriate genomic or molecular factors of the cancer cells, any co-existing medical conditions, etc.

Last but not least, we also take into account important personal considerations, that is, what matters in terms of the patient’s lifestyle, work, relationships, and any other preferences that influence his choice. By being thorough, we are assured that the patient is qualified as an excellent focal therapy candidate.

What role does mpMRI play in focal therapy?

mpMRI is a game-changer that plays five roles in focal therapy:

1. mpMRI helps determine focal therapy candidates. Thanks to its ability to define prostate anatomy and to distinguish cancer from healthy tissue, mpMRI rules focal therapy in or out as a treatment option.
2. mpMRI makes treatment planning possible. It reveals the location and extent of lesions.
3. mpMRI guides focal treatment. It allows the doctor to see in real time the placement of devices used to apply focal therapy; special software shows the effect of the treatment as it is happening, and assures that the targeted lesion plus a safety margin is encompassed by the treatment method.
4. mpMRI affirms treatment success. Immediately following the procedure, scanning the prostate confirms the zone of ablation and the absence of cancer activity.
5. mpMRI is used for follow-up monitoring, with repeat scans at intervals as prescribed by the doctor. This assures that any new disease in the untreated portion of the prostate is detected at the earliest possible time when re-treatment options can be planned if needed.

Is there an mpMRI scoring system for monitoring patients after focal ablation?

Yes, there is a three-tier scoring system called PI-FAB (Prostate Imaging after Focal Ablation). Although not yet widely used, it helps prioritize the need for follow-up. This table shows the tiers:

Can PSMA imaging also be used for follow-up monitoring?

PSMA imaging is a recent innovation in prostate cancer imaging. PSMA stands for Prostate Specific Membrane Antigen, a surface protein more abundant in tumors than healthy prostate cells. PSMA imaging involves use of a radioactive isotope attached to a molecule that prostate cells take in. The isotope “lights up” on imaging scans, revealing the location of even very small prostate locations in the body.

PSMA imaging can be thought of as the new “darling of prostate cancer imaging” for two situations:

• Staging to detect advanced or metastatic disease before primary (first) treatment, and
• Detection/localizing recurrence if PSA is rising following primary treatment.

Thus, PSMA scans are crucial for making treatment decisions in these cases. PSMA scans are usually performed on a CT scanner (PSMA-CT), though MRI can also be used for PSMA imaging.

Now, a team of Italian researchers has proposed the use of PSMA-CT to monitor focal therapy patients during follow-up. In a July 2025 paper they propose a scoring system called PSMA Focal Ablation Imaging (PSMA-FAB) that mirrors the above PI-FAB:

In addition, the team suggests a combined Focal-therapy Imaging Response Evaluation Score (FIRE-SCORE) embedding PI-FAB and PSMA-FAB scores to help patient’s management at follow up.^[ii]

Would PSMA improve focal treatment monitoring?

PSMA would not necessarily improve monitoring after focal therapy. At present, mpMRI is the imaging standard and preferred tool for routine follow-up after focal therapy. However, PSMA may offer an advantage in certain cases such as suspected recurrence, or if mpMRI is ambiguous.

Frequently Asked Questions

Q: What focal ablation methods does the Sperling Prostate Center offer?

A: The Sperling Prostate Center offers Focal Laser Ablation, Focal TULSA, and Exablate MRI-targeted Focused Ultrasound for focal treatment.

Q: What are the side effects of focal therapy?

A: Focal therapy has greatly reduced risks of urinary and sexual side effects compared to whole gland surgery or radiation. According to a review of various focal therapy methods, the rate of reported post-treatment incontinence ranges from 0-3% and erectile dysfunction from 3-50%. Rates vary based on practitioner experience, baseline function prior to treatment, size/location of the tumor, and the method used (cryo, HIFU, focal laser ablation, TULSA, etc.)

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.

References

[i] Lopci E, Lazzeri M, Fasulo V, Maffei D et al. Prostate specific membrane antigen focal ablation imaging (PSMA-FAB). Prostate Cancer Prostatic Dis. 2025 Jul 30.
[ii] Ibid.

About Dr. Dan Sperling

Dan Sperling, MD, DABR, is a board certified radiologist who is globally recognized as a leader in multiparametric MRI for the detection and diagnosis of a range of disease conditions. As Medical Director of the Sperling Prostate Center, Sperling Medical Group and Sperling Neurosurgery Associates, he and his team are on the leading edge of significant change in medical practice. He is the co-author of the new patient book Redefining Prostate Cancer, and is a contributing author on over 25 published studies. For more information, contact the Sperling Prostate Center.