New pain-free treatment for prostate cancer? Not quite

October 3, 2013 by Mark Frydenberg, The Conversation
Focal therapy targets and kills only the index cancer calls using heat, cold, or electric currents. Credit: Shutterstock.com

If you or someone close to you has lived with prostate cancer, you've probably come across dozens of emerging treatments in your hours of Googling. One such treatment, focal therapy, has been dubbed the "new pain-free treatment for prostate cancer". But don't hold your breath; it's still in its experimental phases.

So, what exactly is focal therapy? And what barriers do we need to overcome before it's made available?

Prostate cancer is the nation's second most common cancer, with around 19,000 new diagnoses each year. This type of cancer is multi-focal, meaning it's found in more than one location in the prostate at a time. The largest tumour – known as the index lesion – is the main cancer that can spread to other parts of the body and lead to a reduced rate of survival.

Focal therapy targets and kills only the index cancer cells with either cryotherapy (freezing), high-intensity focused ultrasound (intense heating), laser-induced interstitial thermotherapy (intense heating) and irreversible electroporation (cell destruction). The idea is that by not treating the entire prostate, the untoward from surgery or radiotherapy can be avoided.

But focal therapy works on the assumption that this index lesion is primarily responsible for cancer recurring, and that this lesion can reliably be imaged, biopsied and specifically treated.

It also assumes that targeting this lesion for focal may lead to equivalent long-term cancer survivals compared with whole-gland therapies such as surgery or radiotherapy – with fewer side effects. And that if unsuccessful, these therapies can be introduced safely, without compounding side effects.

But to date, these assumptions are unproven.

Next steps for research

It's too early to routinely recommend focal therapy to treat because key questions remain about its safety and efficacy. More specifically, researchers are investigating the following key areas.

First is whether the index lesion can be accurately identified. While a type of magnetic resonance imaging technique called multi-parametric MRI may be able to improve cancer identification within the prostate, it also has the potential to miss significant cancers.

Current technology does not allow for a lesion seen on MRI to be reliably seen on an ultrasound, which is technology currently used to perform the biopsy. This means there is the potential for error in both the diagnosis of a cancer (its size, position and how aggressive it is) and its subsequent focal treatment. After all, if you can't see it, how are you going to biopsy it, yet alone treat it accurately?

Second, cancer control rates following focal therapies are largely unknown compared with standard whole-gland therapies (such as surgery). Added to this, few focal therapy reports have systematically reported quality of life outcomes such as incontinence or erectile dysfunction using validated tools. As such, the side effects of these treatments are largely unknown.

Third, the feasibility, efficacy and safety of whole-gland therapies used to salvage failed focal therapy is unknown. And the impact of leaving the non-index lesions untreated is also unknown.

Finally, with no no formal definition as to what constitutes treatment failure, there are significant challenges in determining how to monitor patients following focal therapy.

What does this mean for me?

Focal therapy isn't a substitute for active surveillance and men with small, low-risk cancers should be reassured that their risk of cancer death over a 10- to 15-year time frame is extremely low. For these men, it's safe to monitor the situation and have treatment only if the tumour worsens. This avoids the side effects of unnecessary treatments.

The lack of clear evidence of the superiority of focal therapy (or even equivalence) to standard therapies in outcomes, and the largely unknown spectrum and severity of side effects, should not be understated. So if you do need treatment, opt for one of the proven effective therapies such as surgery or radiotherapy.

If you do wish to undergo focal therapy, it's important you do so as part of a formal clinical trial, with appropriate ethics committee approval, consent process and with strict reporting requirements regarding outcomes and safety profile.

Is worth studying scientifically? The answer is absolutely yes, but under formal clinical trial conditions. Is it ready for prime time? Not in 2013.

Explore further: MRI-guided cryoablation viable for recurrent prostate cancer

Related Stories

MRI-guided cryoablation viable for recurrent prostate cancer

August 9, 2013
(HealthDay)—In men with recurrent prostate cancer following radiation therapy, magnetic resonance imaging (MRI)-guided focal cryoablation is feasible and seems safe, according to a study published in the August issue of ...

Focal therapy offers middle ground for some prostate cancer patients

March 5, 2013
Men with low-risk prostate cancer who previously had to choose between aggressive treatment, with the potential for significant side effects, and active surveillance, with the risk of disease progression, may have a new option. ...

Radiotherapy could spare bladder cancer patients surgery

October 1, 2013
Radiotherapy is an effective treatment for aggressive bladder cancer and could spare patients surgery that removes the whole bladder, according to a study published in this month's International Journal of Radiation Oncology ...

Targeted therapy using sound-waves offers 'male lumpectomy' for prostate cancer

April 17, 2012
(Medical Xpress) -- A new type of prostate cancer treatment, which uses sound waves to selectively target individual cancer sites, could provide an alternative to traditional treatment with significantly fewer side effects, ...

Two radiotherapy treatments show similar morbidity, cancer control after prostatectomy

May 20, 2013
Intensity-modulated radiation therapy has become the most commonly used type of radiation in prostate cancer, but research from the University of North Carolina suggests that the therapy may not be more effective than older, ...

Recommended for you

Study: Cells of three advanced cancers die with drug-like compounds that reverse chemo failure

January 23, 2018
Researchers at Southern Methodist University have discovered three drug-like compounds that successfully reverse chemotherapy failure in three of the most commonly aggressive cancers—ovarian, prostate and breast.

'Hijacker' drives cancer in some patients with high-risk neuroblastoma

January 23, 2018
Researchers have identified mechanisms that drive about 10 percent of high-risk neuroblastoma cases and have used a new approach to show how the cancer genome "hijacks" DNA that regulates other genes. The resulting insights ...

Enzyme inhibitor combined with chemotherapy delays glioblastoma growth

January 23, 2018
In animal experiments, a human-derived glioblastoma significantly regressed when treated with the combination of an experimental enzyme inhibitor and the standard glioblastoma chemotherapy drug, temozolomide.

Scientists block the siren call of two aggressive cancers

January 23, 2018
Aggressive cancers like glioblastoma and metastatic breast cancer have in common a siren call that beckons the bone marrow to send along whatever the tumors need to survive and thrive.

Researchers identify a protein that keeps metastatic breast cancer cells dormant

January 23, 2018
A study headed by ICREA researcher Roger Gomis at the Institute for Research in Biomedicine (IRB Barcelona) has identified the genes involved in the latent asymptomatic state of breast cancer metastases. The work sheds light ...

Boosting cancer therapy with cross-dressed immune cells

January 22, 2018
Researchers at EPFL have created artificial molecules that can help the immune system to recognize and attack cancer tumors. The study is published in Nature Methods.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

Elucidated1
not rated yet Oct 03, 2013
Mark, You provide an argument that HIFU is not ready for prime time yet you do not cite any study to support your point. Why is that? Have you ever witnessed or performed a HIFU?
To be clear, I am a walking and talking patient of successful HIFU with no cancer and no side effects. And there are thousands more like me in the US. Did you know HIFU is successfully being done in 30 countries?
Did you know that the same complaints you have against HIFU can be made for radiation and daVinci robotic surgery, where lawsuits abound? Not convenient, is it?

What IS true is that like any procedure HIFU is very successful under an experienced physician, just like RALP. And the fact that after a decade of robotic surgery and different forms of radiation that have had many issues with regard to sparing the nerve bundle, why is there NO peer reviewed comparative study of those two treatments?
I'll look forward to your citations.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.