Ablatherm vs Sonablate (Page 2 of 8)

Article Published by The Prostate Journal

We have received several inquiries regarding an article published online for The Prostate and felt it was important to provide a clarification as well as some observations on the described study. This study was performed at Indiana University using the Sonablate® 500. In fact, Liang Cheng co-authored this study as well as the Phase I/II study described here.

Here is a summary of the article.

NEW YORK (Reuters Health), May 10, 2010 - A range of changes, from necrosis to subtle cellular damage, is common in prostate biopsies taken 180 days after high-intensity focused ultrasound (HIFU) treatment.

This conclusion is based on needle biopsy samples from 25 prostate cancer patients treated with HIFU -- the largest study so far to focus on detailed histological findings from prostate biopsies after HIFU therapy, its authors say.

The main finding, reported online April 16 in The Prostate, was that a variety of changes are possible, including coagulation necrosis, stromal fibrosis, edema, and atypical fibroblast proliferation, said Dr. Liang Cheng of the Indiana University School of Medicine and colleagues.

Necrosis was typically accompanied by acute, chronic, or granulomatous inflammation. Interestingly, in the nearly half of patients (44%) who had residual adenocarcinoma, most biopsy specimens did not show treatment effects.

Pathologists should be aware of the typical pathology findings after HIFU, Dr. Cheng told Reuters Health in a phone interview. They should also be aware that the patient may well still have cancer, although it's currently too difficult to judge the likelihood of that, he explained, since there are "many, many variables" involved.

The finding that many biopsy samples failed to show substantial morphological changes in residual adenocarcinoma indicates that there is substantial room for improvement in HIFU technique, which is still relatively early in its development, Dr. Cheng said.

Dr. Cheng and his co-authors note that Gleason grade should be routinely reported in post-HIFU needle biopsies when prostatic adenocarcinoma is still present. Dr. Cheng emphasized that this assessment is important to determining the strategy for follow-up treatment.

The 25 patients, ranging from 44 to 72 years of age (average 64), received HIFU therapy between 2002 and 2006 at a single center.

Eighteen patients (72%) had coagulation necrosis. All patients had mild or moderate inflammation.

While it is encouraging that scientific study is being performed on the North American results of Sonablate® 500 treatments, these results are less than ideal and do not mirror the results obtained using the Ablatherm device.

Dr. Cheng reported that 11 of 25 patients (44%) had residual prostate cancer after treatment. Moreover, in 9 of those 11 cases (88%), the prostate tissue showed no treatment effects at all!

George Suarez, the Medical Director, Emeritus of USHIFU, the manufacturer of the Sonablate® 500, said in an interview with Nightline that they rely on anecdotal evidence to track results.

http://abcnews.go.com/Health/story?id=4537744&page=3

"Suarez says USHIFU has treated more than 1,000 men in the last five years in Cancun, Canada and across the Caribbean, but he only tracks medical results by what he calls patient "testimonials." He can't supply solid scientific data that proves his patients are cancer free with fewer side effects."

This is in stark contrast to the North American results that have been widely reported by Maple Leaf HIFU physicians at meetings of the American Urological Association, The American Society of Clinical Oncology, The Canadian Urological Association and multiple regional and European meetings. Results have also been submitted for publication to urological journals in the United States.

The most recent study includes 231 patients with low and medium risk category disease who were treated with a single high intensity focused ultrasound treatment without any prior surgical intervention (i.e. no TURP). The average patient age is 63 years. Patients were treated in an ambulatory environment and none required hospital admission for treatment related complications. Three year outcome data using the Horowitz modification of the ASTRO (American Society for Therapeutic Radiation Oncology) criteria show an 84% and 80% success rate for low and medium risk group patients.

Average follow up was 24 months with a range of 12 to 42 months. Complications have been very low and, as was found in the European data, grade three urinary incontinence is virtually non-existent. The most common post-treatment complications include delayed return to normal voiding and an 11% risk of urethral stricture formation which, again, is competitive with other treatment modalities. In the 231 patient cohort reported on there have been only 17 proven local recurrences of prostate cancer (7%) all of which were treated by secondary means (2/3 had repeat HIFU). Post treatment quality of life surveys have shown minimal impact on overall quality of life for the very large majority of patients in this study.

The relatively short follow up for an oncology outcomes study is mitigated somewhat by the observation that over 80% of the adverse events in terms of treatment failure occur in the first year following treatment and all patients in this study have at least one year follow up.

Next Topic: Key Differences Between Ablatherm and Sonablate