Why focal therapy for some types of prostate cancer will become the next mainstream treatment option…
Snowflakes fell silently, dusting the surrounding hills of Kyoto. Indoors, the engine of a new movement in #prostatecancer was starting to hum. The 11th International Symposium in Focal Therapy and Imaging for Prostate and Kidney Cancer brought together pioneers and neophytes in #focaltherapy from all over the globe, and there was a sense among us that focal therapy’s time had come.
What is focal therapy?
Focal therapy, when applied to the prostate, is any image-guided treatment of prostate cancer that deliberately avoids treating the whole prostate gland. Instead it targets the cancerous tumour, leaving the remaining prostate intact.
Why would we want to do that?
Treating the tumour rather than the whole organ it occupies has become commonplace for some cancers so that the affected organ can go on functioning normally. In breast cancer, for example, lumpectomy is performed for some tumours instead of total mastectomy to preserve the remaining breast. Small kidney cancers are usually removed on their own, leaving the rest of the kidney to keep doing its job of filtering blood.
The prostate happens to sit smack bang in the middle of a bunch of pretty important anatomy. Think bladder, bowel, erectile nerves (for erectile function) and urinary sphincter (for urinary continence). The function of the prostate itself (to produce and transmit semen) is usually not so important for older men who have done their fathering of children. But when we treat the whole prostate for cancer, however we do it, any or all of the surrounding structures can get damaged, leading to some loss in their function, and subsequently in quality of life.
For aggressive and bulky prostate cancers, sometimes there’s no choice but to treat the whole prostate and risk the side effects if we aim to cure the cancer. At the other end of the spectrum, most low-grade prostate cancers are harmless and don’t require any treatment at all. But for prostate cancers somewhere in the middle, focal therapy may just be the answer to avoid injury to surrounding structures, keeping quality of life intact, while still curing the disease.
This sounds so obvious! Why isn’t focal therapy a mainstream option now?
A few reasons. First, to cure localized prostate cancer with focal therapy, you’ve got to know exactly where the tumour is and how big it is: location and extent. For success, focal therapy has to be guided by accurate imaging. Until recently, we haven’t had the imaging technology to do this. But now we’ve got multiparametric MRI and a standardised scoring system (PIRADS v.2) to interpret the scans. Evidence is burgeoning around the world showing us that, when read by experts, prostate MRI can be far more accurate in cancer detection and localization than a random biopsy of the gland. This is one of the reasons why focal therapy is about to take off.
Note the catch here though: “when read by experts.” We know that prostate MRI is notoriously tricky to interpret unless you’re properly trained and have read hundreds of cases. Such expertise is extremely limited at present. This is where workshops like the Cambridge Prostate MRI Workshop which I’ve just helped run at the conference in Kyoto (next one in Cambridge UK in May) comes in.
It’s also where MRI PRO comes in. Using 300 tissue-verified high-quality cases, this online training program in prostate MRI, which I created with my colleague Dr Rowan Miller, is designed to train radiologists and urologists around the world in how to read prostate MRI accurately – at scale. And we’ve gathered together the world’s best to advise on it. We’re also thrilled to gain the support of the Movember Foundation, whose mission of improving prostate cancer outcomes aligns perfectly with ours.
MRI PRO’s aim is to vastly increase the accuracy of prostate cancer diagnosis (a global unmet need) around the world. In doing so, it can also help get focal therapy off the ground for the appropriate patients.
Another reason you won’t find focal therapy in any current official clinical guidelines is the lack of high-volume, high-quality evidence. Which is why it is so important that all of us with an interest and vision in this field must collect data and perform clinical trials. It was resolved in Kyoto that this is the top priority.
And finally, many have been worried about focal therapy’s suitability in the prostate because prostate cancer is so often multifocal – that is, tumours frequently occur in multiple areas within the prostate at the same time. However, this is just another reason why accurate imaging, which can identify these tumours, and subsequent thorough tissue biopsy confirmation is so important – so that patients aren’t offered focal therapy inappropriately.
Why else is focal therapy about to take off?
I hope you’re familiar with the term #patient-centred care. It’s a term that has become increasingly prominent, as it should. Unfortunately, sometimes it is only paid lip service. Focal therapy, however, has at its heart the concept of patient-centred care. By combining the chance of cure with minimising risk to quality of life, it provides patients an additional choice of risk/benefit ratio for them to settle on that suits their preferences. In the era of patient-centred care, focal therapy has the great potential to tick all the boxes. As such, with a critical mass of community awareness, it may even be that patients themselves end up being the real drivers of progress in focal therapy.
The future is here
Focal therapy promises to change the game in the treatment of medium-risk localized prostate cancer. It’s truly exciting. But there is much work to be done. Anyone performing focal therapy should be obliged to collect data for quality assurance as an absolute minimum, preferably on a prospective registry. And we must also conduct randomised clinical trials to build a body of high-level evidence.
Following the collaborative resolve seen and felt amongst the snow-dusted hills of Kyoto, I have no doubt that this work will get done. Until then, patients currently offered focal therapy must be informed that it is not considered standard of care (– yet).
*Please note: statements made in this post are my own and do not represent any organisation I work with. In addition, none of the above can be taken as medical advice for individual patients. Such advice can only be properly given following a specialist consultation where all the individual’s relevant information is known.