Date Added: 10/06/2015

Date Updated: 10/06/2015

Ablative Techniques for the Treatment of Localised Prostate Cancer

Specialties: Radiology, imaging & nuclear medicine - Oncology & radiotherapy - Mens Health & Sexual Health

Technology Type: Devices - Procedures

Stage of development: Experimental - pilot or phase II

Stage of EAA: Assessment Complete

Description, patients and keywords:
Prostate cancer is common and is increasingly detected in its early stages through prostate-specific antigen (PSA) screening. The traditional approach to localised prostate cancer involves removal of the whole prostate gland. While this is designed to maximise the likelihood of a cure, it is also associated with a range of adverse effects in the adjacent genitourinary and gastrointestinal systems.
Presented in this report are four emerging technologies that aim to treat localised prostate cancer by focal tissue ablation using various forms of energy (1), rather than by removal of the whole prostate gland. The four technologies and the forms of energy they use are:
1. Cryosurgery / cryotherapy / cryoablation (via extreme cold);
2. Radiofrequency ablation (RFA) (via heat);
3. Irreversible electroporation (IRE) (via electric current);
4. Magnetic resonance (MR)-guided focal laser ablation (via heat).
All techniques employ similar overall approaches. With the patient in the operating room under general (or in some cases, spinal) anaesthesia, several needle electrodes are passed through the perineal skin into the targeted prostate tissue using imaging guidance. The type of imaging guidance varies by technique, and may include transrectal ultrasound [TRUS], magnetic resonance [MR] imaging, or MR-TRUS fusion.(1)
Cryosurgery: gas at temperatures colder than -40â—¦ C is passed through needle electrodes, creating ice balls that destroy the targeted tissue in several freeze-thaw cycles.(2, 3) Cryoablation of the prostate was first introduced in the 1960s; however, it was abandoned due to an unacceptably high complication rate. It was reintroduced in the 1990s as a result of improvements in percutaneous and cryogenic instrumentation, and the development of TRUS, which allowed monitoring of the freezing process. (2, 4)
RFA: thermal energy, at a temperature of about 100°C, is generated from high frequency alternating current by a radiofrequency generator. The thermal energy is delivered to the prostate tumour(s) through monopolar or bipolar needle electrodes and the targeted tissue is irreversibly destroyed by coagulative necrosis.(5)
IRE: low voltage direct electric current delivered via multiple electrodes. This creates a strong electrical field that permanently damages cell membranes, leading to cell death, without a thermal effect.(1)
MR-guided focal laser ablation: thermal energy is used for tissue destruction, leading to homogeneous tissue necrosis. MR imaging can be used during the treatment to provide real-time temperature monitoring and visualisation of the treatment zone. (6)

This report is work in progress and should not be used for external distribution without permission from the originating agency. Users should be aware that reports are based on information available at the time of research and often on a limited literature search.