Thursday, March 10, 2011
March 10, 2011 — High-intensity focused ultrasound (HIFU) has moved from salvage treatment for prostate cancer to being considered for front-line use, although both the US Food and Drug Administration and the European Association of Urology classify HIFU as experimental.
The first case series to report outcomes in men after failed whole-gland HIFU and salvage radical prostatectomy suggests that there is reason for caution.
The pathology results were "alarming," and morbidity was higher after salvage prostatectomy than after primary surgery, researchers report in the March issue of the Journal of Urology.
The findings come from 15 patients treated with HIFU by Nathan Lawrentschuk, MD, from the Department of Surgical Oncology at Princess Margaret Hospital in Toronto, Ontario, and colleagues in Melbourne and Sydney, Australia.
In this case series, pathologically extensive periprostatic fibrosis with persistent prostate cancer (pT3) was seen in 9 of 14 patients, and focally positive margins (pT3a) were seen in 3 of 11 patients. The authors note that early follow-up data suggest acceptable disease control after the salvage prostatectomies.
In an accompanying editorial comment, Declan G. Murphy, MD, from the Department of Urological Oncology at the Peter MacCallum Cancer Centre in Melbourne, Australia, writes: "Whether it is that standard prostate biopsy cannot be relied on to predict final pathological outcome, or that HIFU 'makes cancer angry,' patients should be fully counseled about what we know and, importantly, what we do not know about HIFU treatment for localized prostate cancer today."
"Our own initial experience with HIFU treatment for primary and recurrent prostate cancer unfortunately led us to conclude that the technology is not yet suitable for mainstream clinical practice, and led us to suspend our program," Dr. Murphy added.
Dr. Lawrentschuk told Medscape Medical News that the case series shows that radical prostatectomy as salvage is feasible after the failure of primary HIFU, but that the rate of extraprostatic extension is a concern.
Dr. Lawrentschuk said that "HIFU is experimental and should only be done in studies where patients are told of the risks of failure and the poor results of salvage. They need very careful monitoring, follow-up biopsies, etc. I do not advise patients to have HIFU. There may be a problem with HIFU selecting out more aggressive cells, but this warrants further study."
I think HIFU is inadequate in its current form.
"Experimental treatments are fraught with danger. I was surprised at the aggressive nature of the disease and the recurrences in this supposedly low-risk group," Dr. Lawrentschuk said. "I think HIFU is inadequate in its current form, perhaps because of poor patient selection for HIFU and a lack of standardized ways of detecting post-HIFU recurrences in a timely fashion."
Howard Sandler, MD, chair of radiation oncology at Cedars-Sinai Medical Center's Samuel Oschin Comprehensive Cancer Institute in Los Angeles, California, reviewed the study for Medscape Medical News.
"I wouldn't conclude that the high number with extracapsular extension is a result of HIFU. It is more likely that patients who fail HIFU had worse cancers in any case from the start. Additionally, there may have been a bit of a delay after some suspicion of recurrence before salvage surgery was done, given the presurgery PSA [prostate-specific antigen] of 3.8, with the nadir PSA of 1.0. Thus, patients waited on average for their PSA to rise from 1.0 to 3.8 before something was done. During this interval, extracapsular extension may have occurred," Dr. Sandler said.
He noted that HIFU is being tested for whole-gland ablation, although that approach might be waning. However, that there is growing enthusiasm for HIFU (and other modalities) for focal therapy. "I think that HIFU is a poor choice for both approaches," he said.source: www.medscape.com
