HIFU as first-line treatment in 137 Japanese patients

Data from a series of Japanese patients continue to help us to understand the risks and benefits of first-line treatment with high-intensity focused ultrasound (HIFU) for men initially diagnosed with localized prostate cancer and followed for up to 7 years.

Since May 2003, Inoue et al. have treated 137 consecutive patients with T1-2 prostate cancer. All patients were  were treated using Sonablate 500 HIFU equipment, and were subsequently followed for at least 12 months after their last HIFU treatment. A routine prostate biopsy was carried out 6 months post-HIFU, and serum PSA levels were assessed every 3 months. Progression-free survival (PFS) was determined based on the Phoenix definition (PSA nadir + 2 ng/ml), negative histological findings, and the absence of any indication of local or distant metastasis.

The results reported by Inoue et al. are as follows:

  • Average (median) follow-up after HIFU was 36 months (range, 12 to 84 months), and no patient received adjuvant therapy during this period.
  • PSA nadir values occurred at an average of 2 months post-HIFU and the median nadir level was 0.07 ng/ml (range, 0.01 to 2.01 ng/ml).
  • 6/133 patients (4.5 percent)who underwent prostate biopsy or transurethral resection of the prostate at ≥ 6 months after HIFU were positive for cancer.
  • There were no major postoperative complications but, after removal of the urethral catheter, …
    • Urge incontinence was observed 16 patients (12.0 percent).
    • Dysuria (pain on urination) was observed 33 patients (24.8 percent).
  • The overall 5-year rate of progression-free survival (5-year PFS) was 78 percent.
    • 5-year PFS was 91 percent for low-risk patients.
    • 5-year PFS was 81 percent for intermediate-risk patients.
    • 5-year PFS was 62 percent for high-risk patients.

The authors conclude that HIFU appears to be an effective, repeatable, and minimally invasive first-line treatment for localized prostate cancer that has particular efficacy in men with low- and intermediate-risk disease. It is interesting to note that Inoue et al. report continued use of a transurethral catheter, whereas others, such as the UK group led by Ahmed and Emberton, rapidly adopted use of a suprapubic catheter. One wonders whether use of a suprapubic catheter would have had any impact on the incidence of urge incontinence and dysuria after removal of the catheter in this series of Japanese patients.

2 Responses

  1. HIFU has been found relatively safe and effective in several studies worldwide. Why can’t it be approved in the U.S.?

  2. HIFU is a new therapeutic technology, and US law requires the manufacturers of this technology to carry out clinical trials that will satisfy the FDA of the safety and effectiveness of this technology. The studies conducted outside the US to date have not been conducted according to US standards. They are simply “case series,” not comparative clinical trials, and they have not consistently tracked all sorts of information that will be required if HIFU is to be approved in the US.

    As far as I can tell:

    (a) Ablatherm has completed enrollment of patients into at least one large Phase III clinical trial in the USA for the use of HIFU as first-line treatment of prostate cancer.

    (b) USHIFU is currently recruiting patients into two large Phase III trials of their Sonablate technology for salvage treatment of men with locally recurrent prostate cancer after prior radiation therapy.

    When these trials will be compete, and whether they will be sufficient to gain approval for HIFU in the USA, I have no idea.

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