From the Guidelines
High-intensity focused ultrasound (HIFU) has not been proven to be a reliable method for destroying cancer tumors, particularly for high-risk localized disease, due to poor long-term oncological outcomes 1. However, there is some evidence to suggest that HIFU may be effective in treating small, low- or intermediate-risk unifocal tumors with focal therapy, aiming to ablate tumors while sparing surrounding healthy tissue. Some key points to consider include:
- Focal HIFU therapy has shown low treatment-related toxicity, with a 4% decrease in pad-free continence and a reduction in the International Index of Erectile Function of 0.4 points 1.
- Oncological outcomes are less clear, with no randomized comparative data, but case series suggest 88% failure-free survival at 5 years, defined as the need for salvage treatment or systemic therapy 1.
- The procedure faces challenges in delivering energy to the anterior part of large prostates, as the US energy is most often delivered from the rectal cavity 1.
- For now, focal therapy should be performed only within the context of a clinical trial setting or a well-designed prospective registry 1. It is essential to weigh the potential benefits and risks of HIFU treatment for each individual patient, considering factors such as cancer type, tumor location, and overall health, and to develop a comprehensive treatment plan in consultation with oncology specialists.
From the Research
Success of Ultrasound in Destroying Cancer Tumors
- High intensity focused ultrasound (HIFU) has been shown to be a promising modality for treating tumors in a non-invasive fashion, with online image guidance and therapy control achieved by magnetic resonance imaging (MRI) or diagnostic ultrasound (US) 2.
- HIFU has been tested in clinical studies for various benign and malignant tumors, including those of the prostate, breast, uterine, liver, kidney, pancreas, bone, and brain, with feasible and safe results 2, 3.
- The technology has the potential to become a serious alternative or adjunct to standard treatment options of surgery, radiotherapy, gene therapy, and chemotherapy in oncology 2.
- HIFU can achieve precise biological effects in tissue with a high safety profile, and is being investigated for advanced applications at the cellular level 4.
- HIFU ablation is a relatively new technology that provides non-invasive treatment for patients with hepatocellular carcinoma (HCC) and liver cirrhosis, and has been shown to be a safe and effective treatment option for selected patients 5.
Clinical Applications of HIFU
- HIFU has been used to treat various types of tumors, including prostate, breast, uterine, liver, kidney, pancreas, bone, and brain tumors 2, 6, 3.
- The technology has been shown to be effective in thermally ablative treatment, therapeutic delivery mechanisms, and neuromodulatory phenomena 6.
- HIFU has been used in combination with other treatment modalities, such as radiofrequency ablation (RFA) and microwave ablation (MWA), to enhance treatment options for patients with HCC 5.
Mechanisms and Future Developments
- HIFU works by delivering high-energy pulses in a spatially coordinated manner, while minimizing damage to tissue outside the target area 6, 3.
- The technology has the potential to become a major instrument to mediate drug and gene delivery for localized cancer treatment 2.
- Future developments in HIFU technology are expected to enhance its clinical applications and outcomes, with ongoing research focusing on improving treatment delivery and efficacy 6, 4.