Over the past decade or so, the use of focal cryotherapy for localized prostate cancer has increased by more than 1,000-fold. Stephen Jones and John Ward have now published a report on the outcomes and complications associated with this procedure based on data from the COLD registry-a prostate cryotherapy internet database. The analysis involved 5,853 patients, 1,160 of whom had received focal treatment.

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The conclusions of this report are encouraging. Focal and whole-gland cryotherapies were associated with almost identical recurrence-free rates 2 years after treatment (75–76%) with a slightly more favorable adverse event profile for focal therapy. Modest improvements in rates of urinary incontinence and retention were observed, as well as a moderate increase in the number of patients able to maintain sexual function (58% compared to 32% in the whole-gland cohort). Although rare in both groups, occurrence of rectourethral fistula was also significantly reduced in patients receiving focal therapy (0.08% versus 0.4% incidence).

Although organ-sparing surgery is becoming the standard surgical treatment option for the majority of solid tumors, its role in the management of prostate cancer is limited by anatomical challenges and tumor multifocality. Despite the promising findings reported by Jones and Ward, focal therapy is unlikely to become standard treatment for patients undergoing cryoablation.

“Focal therapy applies to a very specific population with a limited-size tumor in a confined space. Most patients have tumors that do not fit this description, so it is likely they will require whole gland therapy. Furthermore, it is not completely established whether focal therapy has sustainable cancer control and this has to be considered too,” says Jones. “The aim is to identify when focal therapy can give outcomes that approach those of whole gland therapy while minimizing the associated side effects.”

A current difficulty is selecting parameters to monitor the success of these therapies. For example, serum PSA kinetics will likely differ following focal and total-gland treatment. “We have no good data yet on PSA dynamics following focal therapy. The challenge is identifying how the residual prostate tissue produces PSA,” Jones adds.

Patients currently receiving focal therapy tend to be slightly younger and with lower stage tumors than patients undergoing whole-gland cryoablation. High-risk patients are less likely to be considered for focal therapy. “Because we have not proven sustainable cancer control, high-risk patients—who are likely to have worse outcomes—will probably continue to be treated with whole-gland therapy for the foreseeable future,” explains Jones.