Targeted prostate cancer treatment hopes to minimise side effects

The Icon Cancer Centres in Victoria are using focal low dose rate (LDR) brachytherapy to provide highly targeted radiation for prostate cancer.

The data is being collected as a part of the LIBERATE registry, examining oncologic outcomes and the possible reduction of the side effects such as erectile dysfunction, which are present in other treatments.

While LDR brachytherapy has been a standard treatment option for some years, and offers a similar side effect profile compared to external beam radiation and surgery, the newer focal approach is designed to target the cancer more closely.

The focal treatment is said to be suitable for about 15–25% of prostate cancers that are confined to one area of the prostate and assessed on biopsy as low to intermediate risk.

A targeted approach

Dr Andrew See, radiation oncologist at Icon Cancer Centres and co-lead of the LIBERATE registry, said, “Because of advances in diagnostics and imaging, we now have an unprecedented level of understanding of where the cancer is within the prostate, like having precise GPS coordinates. We can go in with a very targeted approach just to treat that geographic area with a small margin.

Studies into the procedure to insert the seeds have shown it is comparatively quicker, less invasive and with a decreased likelihood of ongoing side effects, such as urinary incontinence and erectile dysfunction, than surgery or external beam radiation.¹

See said, “All prostate cancer treatments come with some level of risk. With active surveillance men can feel a psychological burden of knowing they have cancer, and the ongoing testing can be fatiguing, even when their cancer is not symptomatic.

“We are always looking at how we can kill the cancer whilst reducing risks and side effects for patients.”

Brachytherapy seeds emit radiation for three months, with the cancer being destroyed during this time. The seeds then become inert and do not need to be removed.

Additional advantages

Focal LDR brachytherapy is said to have additional clinical advantage for patients should another prostate cancer be found later in life, with other treatment options remaining available.

“If a new cancer appears on the other side of the prostate, the patient can still have surgery if needed. Successful treatment via focal brachytherapy doesn’t prevent a new cancer occurring later on. We know from surgeon feedback that there is no issue removing the prostate if this occurs, and for those few patients we have still given them perhaps several years with their prostate and without issues of incontinence and sexual dysfunction that could occur from standard treatments of the whole gland,” See said.

So far, 110 men have contributed their data to the registry. See said early results are promising but they will have to wait some years for long-term data.

“The sense is that morbidity is definitely less, and tolerance is much better. Early oncological outcomes are still a few years off, but there’s been no reason not to be positive,” See said.