Focal therapy for prostate cancer
Focal therapy for prostate cancer
Focal laser therapy may offer new options for men with prostate cancer
The idea of focal ablation (localised ‘killing off’) of cancers is not new – surgery for breast cancer was revolutionised years ago by the development of lumpectomy or wide local excision of tumours of the breast, rather than mastectomy (removal of the entire organ), in some settings. This idea has been slow to gain traction in prostate cancer, but may be a sensible option for tumours in the near future.
There are various options for focal ablation, and MRI-guided laser ablation shows a lot of promise in low and intermediate risk prostate cancer. Here, the very accurate application of heat energy from a laser is used to destroy prostate tumours. The position of the laser fibre in the prostate is guided by magnetic resonance imaging (MRI) and ultrasound using a fusion system. This is possible under sedation and local anaesthetic, as shown by a group at UCLA in the States. They first reported their findings in the Journal of Urology back in July 2016 (see here), and they followed up the study with a presentation at the American Urological Association Annual meeting in May 2017 (see here).
Importantly, their study found no serious adverse effects on erections or ability to control urine in their first 18 patients. It is possible that this treatment could be a further option for patients with prostate cancer, improving outcomes by reducing side effects.
One of the concerns often expressed is that focal therapy doesn’t remove the whole prostate and therefore new prostate cancers can grow. Certainly, in some people, prostate cancer is a multifocal disease, meaning there is more than one focus in the prostate and that remaining areas of the prostate could develop cancer. However, this is not true for all patients or all cancers, and in some patients, removal of the entire prostate, with its potential associated problems, is too aggressive. Careful selection of treatment to suit the patient is the important issue, particularly now we have much more accurate ways to visualise the prostate and cancers with multiparametric MRI.
Similar Biobot system used at nRAH
A similar system for biopsy (the ‘Biobot’), using MRI and ultrasound fusion has been used for over 15 months at the Royal Adelaide Hospital (see here).
The next stage in development of the Biobot is a software add-on for the delivery of focal therapy. The system used by the authors of the study was the Artemis, which is similar.
Importantly, the authors of the study felt that they had developed the expertise for focal therapy through the use of MRI fusion biopsy, and that this was excellent experience that allowed them to go on to develop this focal treatment. This form of treatment is not yet available in Australia.
