Robotic High-intensity Focused Ultrasound for Prostate Cancer: What Have We Learned in 15 Years of Clinical Use?

Magnetic Nanoparticle-Mediated Heating for Biomedical Applications

Magnetic nanoparticles, especially superparamagnetic nanoparticles (SPIONs), have attracted tremendous attention for various biomedical applications. Facile synthesis and functionalization together with easy control of the size and shape of SPIONS to customize their unique properties, have made it possible to develop different types of SPIONs tailored for diverse functions/applications. More recently, considerable attention has been paid to the thermal effect of SPIONs for the treatment of diseases like cancer and for nanowarming of cryopreserved/banked cells, tissues, and organs. In this mini-review, recent advances on the magnetic heating effect of SPIONs for magnetothermal therapy and enhancement of cryopreservation of cells, tissues, and organs, are discussed, together with the non-magnetic heating effect (i.e., high Intensity focused ultrasound or HIFU-activated heating) of SPIONs for cancer therapy. Furthermore, challenges facing the use of magnetic nanoparticles in these biomedical applications are presented.

High-Intensity Focused Ultrasound for the Treatment of Prostate Cancer: A Review

Over the past 25 years, the average life expectancy for men has increased almost 4 years, and the age of prostate cancer detection has decreased an average of 10 years with diagnosis increasingly made at early-stage disease where curative therapy is possible. These changing trends in the age and extent of malignancy at diagnosis have revealed limitations in conventional curative therapies for prostate cancer, including a significant risk of aggressive cancer recurrence, and the risk of long-term genitourinary morbidity and its detrimental impact on patient's quality of life (QOL). Greater awareness of the shortcomings in radical prostatectomy, external radiotherapy, and brachytherapy has prompted the search for alternative curative therapies that offer comparable rates of cancer control and less treatment-related morbidity to better preserve QOL. High-intensity focused ultrasound (HIFU) possesses characteristics that make it an attractive curative therapy option. HIFU is a noninvasive approach that uses precisely delivered ultrasound energy to achieve tumor cell necrosis without radiation or surgical excision. In current urologic oncology, HIFU is used clinically in the treatment of prostate cancer and is under experimental investigation for therapeutic use in multiple malignancies. Clinical research on HIFU therapy for localized prostate cancer began in the 1990s, and there have now been ∼65,000 prostate cancer patients treated with HIFU, predominantly with the Ablatherm (EDAP TMS, Lyon, France) device. Neoadjuvant transurethral resection of the prostate has been combined with HIFU since 2000 to reduce prostate size, facilitate tissue destruction, and to minimize side effects. Advances in imaging technologies are expected to further improve the already superior efficacy and morbidity outcomes, and ongoing investigation of HIFU as a focal therapy in salvage and palliative indications is serving to expand the role of HIFU as a highly versatile noninvasive therapy for prostate cancer.

Quality of life and functional outcome after infravesical desobstruction and HIFU treatment for localized prostate cancer

Background

To evaluate quality of life, functional and oncological outcome after infravesical desobstruction and HIFU treatment for localized prostate cancer.

Methods

One hundred thirty-one patients, treated with TURP and HIFU in a single institution were followed up for oncological and functional outcome. Oncological outcome was quantified by biochemical recurrence free survival using the Stuttgart and Phoenix criteria. Quality of life was assessed by usage of standardized QLQ-C30 and QLQ-PR25 questionnaires. In addition, functional questionnaires such as IPSS and IIEF-5 were used. Complications were assessed by the Clavien-Dindo classification.

Results

One hundred thirty-one patients with a mean age of 72.8 years (SD: 6.0) underwent HIFU for prostate cancer (29.0% low risk, 58.8% intermediate risk, 12.2% high risk). PSA nadir was 0.6 ng/ml (SD: 1.2) after a mean of 4.6 months (SD: 5.7). Biochemical recurrence free survival defined by Stuttgart criteria was 73.7%, 84.4% and 62.5% for low-, intermediate- and high-risk patients after 22.2 months. Complications were grouped according to Clavien-Dindo and occurred in 10.7% (grade II) and 11.5% (grade IIIa) of cases. 35.1% of patients needed further treatment for bladder neck stricture. Regarding incontinence, 14.3%, 2.9% and 0% of patients had de novo urinary incontinence grade I°, II° and III° and 3.8% urge incontinence due to HIFU treatment. Patients were asked for the ability to have intercourse: 15.8%, 58.6% and 66.7% of patients after non-, onesided and bothsided nervesparing procedure were able to obtain sufficient erection for intercourse, respectively. Regarding quality of life, mean global health score according to QLQ-C30 was 69.4%.

Conclusion

HIFU treatment for localized prostate cancer shows acceptable oncological safety. Quality of life after HIFU is better than in the general population and ranges within those of standard treatment options compared to literature. HIFU seems a safe valuable treatment alternative for patients not suitable for standard treatment.

Robotic Assisted Laparoscopic Prostatectomy after High Intensity Focused Ultrasound Failure

Background. Prostate cancer is the most common cancer diagnosed in men. As new focal therapies become more popular in treatment of prostate cancer, failure cases requiring salvage therapy with either surgical or other techniques are being reported. Objective. To report the options in treatment of prostate cancer after recurrence or failure of the primary treatment modality. Methods. We report a salvage robotic assisted laparoscopic radical prostatectomy (RALP) for prostate cancer recurrence following high intensity focused ultrasound treatment (HIFU) in the United States. Results. A 67-year-old man who underwent HIFU treatment for prostate adenocarcinoma 2 years prior was presented with a rising prostate specific antigen of 6.1 ng/mL to our clinic. A biopsy proven recurrent disease in the area of previous treatment documented the failure of treatment. The patient elected to undergo a salvage RALP. The operation time was 159 minutes. The patient was discharged from the hospital on postoperative day 1 with no complications. The catheter was removed on post-op day 10. The patient reserved sexual function and urinary continence. The PSA levels on 6 months' follow-up are undetectable. Conclusions. Salvage RALP is an effective and safe treatment choice for recurrent prostate adenocarcinoma following failed HIFU treatment if operated by an experienced surgeon.

Single application of high-intensity focused ultrasound as a first-line therapy for clinically localized prostate cancer: 5-year outcomes

Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? High-intensity focused ultrasound (HIFU) therapy has been proposed for the treatment of localized prostate cancer (PCa) for all risk levels of tumour recurrence. The study adds data on the efficacy of a single HIFU application in the treatment of PCa with different risks of recurrence. Durable cancer control was achieved in 81.7% of patients with low-risk disease, with rates of efficacy declining in intermediate- and high-risk tumours. The data suggest that the principal domain for minimal invasive HIFU should be low-risk disease.

OBJECTIVE

• To report cancer control results after a single application of high-intensity focused ultrasonography (HIFU) in patients with localized prostate cancer (PCa), stratified by tumour recurrence risk according to D'Amico risk classification.

PATIENTS AND METHODS

• In a retrospective single-centre study, we analysed the outcomes of patients with localized PCa who were treated with curative intent between December 2002 and October 2006 using an Ablatherm HIFU device (EDAP-TMS, France). • Transurethral resection of the prostate or adenomectomy were performed before HIFU to downsize large prostate glands. • Oncological failure was determined by the occurrence of biochemical relapse, positive biopsy and/or metastasis. Biochemical relapse was defined as a PSA nadir +1.2 ng/mL (Stuttgart definition), or as a rise in PSA level to ≥ 0.5 ng/mL if PSA doubling time was ≤ 6 months. Kaplan-Meier analysis was performed for survival estimates.

RESULTS

• A total of 191 consecutive patients were included in the study. The median (range) patient age was 69.7 (51-82) years, and 38, 34 and 28% of these patients were in the low-, intermediate- and high-risk groups, respectively. • The median (range) follow-up was 52.8 (0.2-79.8) months. • At 5 years, overall and cancer-specific survival rates were 86.3% and 98.4%, respectively. • Stratified by risk group, negative biopsy rates were 84.2%, 63.6%, and 67.5% (P = 0.032), 5-year biochemical-free survival rates were 84.8%, 64.9% and 54.9% (P< 0.01), and 5-year disease-free survival rates were 81.7%, 53.2% and 51.2% (P < 0.01), respectively.

CONCLUSION

• Single-session HIFU is recommended as a curative approach in elderly patients with low-risk PCa. Patients at higher risk of tumour progression should be counselled regarding the likely need for salvage therapy, including repeat HIFU.