Prostate Cancer Focal Ablation Can Be a Reasonable Option
Patient selection and physician-patient commitment to careful follow-up surveillance are key to successful focal therapy.
|The following article is part of conference coverage from the 2018 Large Urology Group Practice Association meeting in Chicago, November 1-3. Renal and Urology News' staff will be reporting on presentations dealing with various practice management and clinical topics aimed at community-based urologists. Check back for the latest news from LUGPA 2018.|
CHICAGO—Current imaging and biopsy capabilities make it possible for urologists to identify men for whom focal therapy for prostate cancer (PCa) is a reasonable option, Herbert Lepor, MD, of the New York University School of Medicine, told attendees at the 2018 annual meeting of the Large Urology Group Practice Association.
Although many important aspects of this approach are not known, focal therapy is a minimally invasive procedure done on an outpatient basis and is associated with minimal treatment-related complications and expedited recovery.
“I'm very confident there's no impact on continence and minimal impact on potency,” Dr Lepor said. “I'm uncertain, of course, whether clinically significant recurrences or new tumors will develop during the patient's life expectancy. I'm confident we don't burn bridges for future curative intervention.”
Dr Lepor acknowledged some of the unknowns related to focal ablation, such as the optimal energy that should be used to ablate tissue, the extent of ablation necessary to achieve oncologic control, and the optimal way to assess oncologic control (such as the timing of PSA testing, magnetic resonance imaging [MRI], and biopsies). Moreover, no intermediate- or long-term outcome data are available.
Careful patient selection is paramount. For a patient to be a good candidate for focal therapy, he should meet certain criteria, which include high-quality pre-treatment multiparametric MRI scans showing unilateral lesions; risk stratification into a Gleason grade group less than 4; no Gleason pattern 4 found on systematic biopsy in the contralateral part the prostate; and no gross extracapsular extension. Other factors that may influence the decision to undergo focal therapy include life expectancy, site, extent, and aggressiveness of the cancer, and outcome priority of the patient.
“A radical prostatectomy can be a very reasonable option, but if someone's going to be devastated by potential complications of sexual dysfunction, then [it] may not be such an excellent option,” he said.
Patients need to be fully informed about the risks and benefits of focal therapy as well as the unknowns. “In counseling patients, it's so critical to give valid outcomes expectations,” Dr Lepor stated.
In addition, patients have to be willing to undergo post-ablation imaging and biopsy. “If you offer this [focal ablation], there must be a commitment on your part and the patient's part for careful follow-up,” he said.
Dr Lepor discussed the findings of a study in which he and his colleagues enrolled 59 men who met criteria for focal ablation but who underwent radical prostatectomy (RP). They examined the RP specimen for the presence of Gleason pattern 4 disease outside of the focal ablation area. Prostate specimens from 15 of the 59 patients (25.4%) had at least 1 Gleason pattern 4 lesion outside of the focal ablation area. Of a total of 20 Gleason pattern 4 lesions, 7 (35%) were ipsilateral and 13 (65%) were contralateral to the MRI-detected lesion. If hemiablation had been performed, some Gleason pattern 4 disease would have been left behind in 18.6% of cases. In virtually all cases, however, that lesion would have been less than 1 mm in diameter, Dr Lepor and colleagues reported in Urology (2018;112:121-125).
He noted that about half of men placed on active surveillance for Gleason grade group 1 disease are found to have Gleason pattern 4 disease after RP. Thus, the patients he selects for focal therapy actually have lower-risk disease remaining after ablation than patients placed on AS, he pointed out.
Of the 200-300 cases of focal ablations for PCa performed at his institution, he related, he has yet to see a patient experience any level of incontinence, even immediately after catheter removal. Erectile function can be affected, however. The greater the extent of the ablation, especially in cases in which a lesion is encroaching on the prostate capsule, the more likely it is that patients will experience transient erectile dysfunction.
At his institution, surgeons usually remove patients' catheters 2 to 4 days after the procedure, depending on the extent of ablation. Patients get PSA tests at 3 months and then every 6 months thereafter. “At the moment, our protocol is every patient at 6 months gets an MRI and a targeted biopsy of the ablation zone.”
If patients have a negative MRI at 6 months and a stable lowering of PSA, the likelihood of finding significant disease in the ablation zone is very low, he said. Consequently, his institution is reassessing its existing follow-up protocol.