Hyperthermia (heating of tissues) was tried many years ago for cancer treatment with very disappointing
results, and was thus discontinued. More recently some centers in Latin America and Europe have been experimenting with HIFU
(high intensity focused ultrasound) to cause a similar thermal effect to treat cancer.
HIFU is associated
with the absorption of ultrasound energy into the prostate and surrounding tissues to cause the heating of cells. Unfortunately,
there is no difference in the damage caused by heat to cancer cells compared to the surrounding normal cells. Because there
is no therapeutic ratio with this modality, there is a greater risk of the heat damaging areas around the prostate such as
the rectum, urethra and nerves.
The outcomes of HIFU treatment for prostate cancer are very poor.
Consequently very few papers are available, with few patients treated and too short follow up of far less than 10 years. A
recent European study published in 2008 showed that the 5 year success rate in France was only 30% with HIFU (Misrai, 2008). One of the largest HIFU series shows only a 59% disease free survival at 7-years for early stage patients
(Blana, European Urology 2008). These results are considerably lower than the published results from larger series with radiation
(94-98% cure rates for similar patients). Toxicity with HIFU in these publications is also high, with incontinence and urethral
strictures much more common (Poissonnier, European Urology 2007).