Transrectal high-intensity focused ultrasound for the treatment of localized prostate cancer: Eight-year experience

Minimally invasive ablative therapies for definitive treatment of localized prostate cancer in the primary setting

Traditionally, the patient with a new diagnosis of localized prostate cancer faces either radical therapy, in the form of surgery or radiation, or active surveillance. A growing subset of these men may not be willing to accept the psychological burden of active surveillance nor the side effects of extirpative or radiation therapy. Local ablative therapies including cryotherapy, high-intensity focused ultrasound, and vascular-targeted photodynamic therapy have emerged as a means for minimally invasive definitive treatment. These treatments are well tolerated with decreased morbidity in association with improvements in technology; however, long-term oncologic efficacy remains to be determined.

In vivo imaging and treatment of solid tumor using integrated photoacoustic imaging and high intensity focused ultrasound system

PURPOSE

The purpose of this study is to show the feasibility of combined contrast imaging and treatment of solid tumor in vivo by an integrated photoacoustic imaging and high intensity focused ultrasound (HIFU) system.

METHODS

During this study, photoacoustic imaging was performed to identify the location of a CT26 tumor, which was subcutaneously inoculated on the hip of a BALB/c mouse. Then the CT26 tumor was ablated by HIFU with the guidance of photoacoustic images. To enhance the contrast and specificity of photoacoustic imaging, gold nanorods were used as the contrast agents during the experiment. After being injected into the blood stream, gold nanorods passively accumulated around the tumor region, and therefore outlined the location and shape of the tumor in the photoacoustic images, which were used to guide the subsequent HIFU therapy.

RESULTS

The experiment results showed that the tumor was clearly visible on photoacoustic images after the injection of gold nanorods and HIFU was able to ablate the tumor under the guidance of photoacoustic imaging.

CONCLUSIONS

The authors demonstrated that their integrated photoacoustic imaging and HIFU system has the potential for contrast imaging with gold nanorods with possible diagnosis and treatment of solid tumors.

Systematic review of the efficacy and safety of high-intensity focussed ultrasound for the primary and salvage treatment of prostate cancer

CONTEXT

High-intensity focussed ultrasound (HIFU) is an emerging minimally invasive treatment option for prostate cancer.

OBJECTIVE

Our aim was to assess the efficacy and safety of HIFU in both primary treatment of men with localised and locally advanced prostate cancer as well as salvage treatment of men with recurrent prostate cancer following treatment failure of radical prostatectomy or external-beam radiation therapy.

EVIDENCE ACQUISITION

We conducted a systematic literature search for studies conducted on humans and published in either English or German in several databases from 2000 to 2010. In addition, we screened several Web sites for assessments on HIFU in prostate cancer and contacted the manufacturers of the two currently available HIFU devices for supplemental information on HIFU. We included all prospective studies with >50 study participants and assessed their quality using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

EVIDENCE SYNTHESIS

We identified 20 uncontrolled prospective case series, each of which treated between 58 and 517 patients. These studies were all conducted within the past decade. In total, 3018 patients were treated with HIFU, 93% for primary therapy and 7% for salvage HIFU. For all HIFU procedures, the biochemical disease-free survival rate at 1, 5, and 7 yr, respectively, was 78-84%, 45-84%, and 69%. The negative biopsy rate was 86% at 3 mo and 80% at 15 mo. Overall survival rates and prostate cancer-specific survival rates were 90% and 100% at 5 yr and 83% and 98% at 8 yr, respectively. Adverse events concerned the urinary tract (1-58%), potency (1-77%), the rectum (0-15%), and pain (1-6%). Quality-of-life assessment yielded controversial results.

CONCLUSIONS

Applying the GRADE approach, the available evidence on efficacy and safety of HIFU in prostate cancer is of very low quality, mainly due to study designs that lack control groups. More research is needed to explore the use of HIFU in prostate cancer.

High-intensity focused ultrasound as salvage therapy for patients with recurrent prostate cancer after external beam radiation, brachytherapy or proton therapy

OBJECTIVE

To investigate the use of high-intensity focused ultrasound (HIFU) as a salvage therapy in patients with recurrence of localized prostate cancer after external beam radiation (EBRT), brachytherapy, or proton therapy.

PATIENTS AND METHODS

We retrospectively reviewed the charts of all patients who had undergone salvage HIFU for biopsy-proven prostate cancer after primary radiation therapy. Patient characteristics and oncological outcomes were assessed.

RESULTS

Records of 22 patients with a median (range) follow-up of 24 (5-80) months were reviewed. Patients were men with presumed organ-confined disease who had been treated with salvage HIFU following recurrent disease after EBRT (fourteen patients), brachytherapy (five patients: four with high-dose brachytherapy using In(192) ; and one with low-dose brachytherapy using Au(98) ) or proton therapy (three patients). The median (range) age at salvage HIFU was 65 (52-80) years, with a median (range) prostate-specific antigen (PSA) level before radiation therapy of 14.3 (5.7-118) ng/mL and a median (range) PSA level of 4.0 (1.2-30.1) ng/mL before HIFU. The median (range) period to HIFU after radiation therapy was 36 (4-96) months. The biochemical disease-free survival (bDFS) rate in all patients at 5 years was 52%. Rates of bDFS in low-, intermediate- and high-risk groups were 100%, 86%, and 14%, respectively. One of the twelve patients who received post-HIFU prostate biopsy showed malignancy. Side effects included urethral stricture in four patients, grade I urinary incontinence in four patients, rectourethral fistula and epididymitis in one of each patient.

CONCLUSION

Salvage HIFU is a promising treatment option for local recurrence after radiation therapy, with morbidity comparable with other forms of salvage treatment.

Quality of life following high-intensity focused ultrasound for the treatment of localized prostate cancer: a prospective study

OBJECTIVES

To report our health-related quality of life (QOL) and functional outcomes following high-intensity focused ultrasound (HIFU) for localized prostate cancer.

METHODS

Data from prostate cancer patients undergoing HIFU at our institution between January 1999 and April 2007 were collected in our prospective database. Standard preoperative and surgical parameters, as well as baseline urinary function, QOL and sexual assessment were included. The Japanese version of the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-prostate (P) and the International Index of Erectile Function-5 (IIEF-5) were used for the functional assessment. These self-administered questionnaires were collected preoperatively and again at 6, 12 and 24 months postoperatively.

RESULTS

A total of 326 patients were included in the analysis. Maximum flow rate and residual urine volume were significantly impaired at 6 months (P = 0.010) after HIFU, even if they returned to baseline values at 12 or 24 months after HIFU. The total FACT-G score significantly improved at 24 months (P = 0.027) after HIFU. At 6, 12 and 24 months after HIFU, 52%, 63% and 78%, respectively, of the patients, not receiving neoadjuvant hormonal therapy, were potent.

CONCLUSIONS

In our experience, functional and QOL outcomes after HIFU therapy for localized prostate cancer are better than those after other treatment modalities.

Salvage high-intensity focused ultrasound for biopsy-confirmed local recurrence of prostate cancer after radical prostatectomy

OBJECTIVE

To present experience in high-intensity focused ultrasound (HIFU) used as a salvage therapy for biopsy-confirmed local recurrence at the vesico-urethral anastomosis after radical prostatectomy (RP).

PATIENTS AND METHODS

From July 2006, four patients diagnosed with prostate cancer recurrence after RP were treated with HIFU, with or without salvage radiotherapy, using the Sonablate 500 (Focus Surgery, IN, USA). Biochemical failure was defined as in increase in prostate-specific antigen (PSA) level of >0.2 ng/mL. No patients received any adjuvant therapy after HIFU therapy before reporting failure.

RESULTS

The mean age and initial PSA level before RP was 74 years and 10.0 ng/mL, respectively. After RP, one patient was stage T2aN0M0, two were stage T3N0M0 and the last had an unknown pathological stage. Three patients received external beam radiotherapy as salvage therapy after RP. The mean PSA level before HIFU, tumour volume at the vesico-urethral lesion and operative duration were 4.3 ng/mL, 4.6 mL and 27 min, respectively. Adenocarcinomas were confirmed by biopsy of the tumour at the vesico-urethral anastomotic lesion before HIFU. At 24 months of follow-up, patients 2 and 4 were classified a biochemically disease-free. Biopsies at the anastomotic site after HIFU in three patients showed no malignancy, with fibrosis. There were no complications.

CONCLUSION

Salvage HIFU for patients with recurrence after RP is feasible, even though they received salvage radiotherapy before HIFU. More patients and a longer follow-up are needed to evaluate the safety and oncological adequacy of this new approach.