Gel implant can spare prostate patients the side-effects of radiotherapy
A NEW treatment for prostate cancer uses a gel implant to stop healthy cells being damaged by radiotherapy. Gordon Robinson, 70, a former electrical wholesaler, from Dungannon, Co. Tyrone, was one of the first UK patients to be given it, as he tells PAT HAGAN. THE PATIENT
As I approached my 70th birthday in July last year, my wife elma suggested I ask my Gp for a general check-up. I felt fine and was fit and active for my age — playing golf two or three times a week — and wasn’t particularly overweight. But elma had been ill with breast cancer a few years earlier and was more aware than me of the need to catch any hidden health problems sooner rather than later.
she insisted I have a blood test to check my psa level, to see if I might have prostate cancer. I’d never been offered the test before, or requested it, but I wasn’t concerned because I was otherwise well.
But my psa score was 7.3 ng/ml — more than double the ‘healthy’ level (3ng/ml) for my age. The result scared me and I was worried that I might have cancer.
The Gp said this was possible but that a high psa level could also be due to non-cancerous conditions. But my worst fears were confirmed a few weeks later when doctors said they had found cancer cells in the tissue sample from a biopsy.
Thankfully, it was low-grade and had not spread beyond the prostate, but I was still completely shocked.
I was prescribed hormonesuppressing drugs, to stop the tumour feeding off testosterone, and a course of the anti-cancer drug tamoxifen, and was referred for radiotherapy at Belfast city hospital.
at a meeting with doctors last autumn, they mentioned they were trialling a new technique to make radiotherapy safer.
although radiotherapy is very good at killing prostate cancer cells, apparently the rays can miss their target and do a lot of damage to the rectum, which sits right next to the prostate.
This can leave you with severe, lifelong diarrhoea, painful ulcers and even regular bleeding from the back passage.
But I was told there was an implant — basically a blob of gel about the size and shape of my little finger — they could put between the prostate and the rectum so there’s much less chance of the radiotherapy beam hitting the rectum.
afterwards, the gel simply breaks down over a period of several months into tiny molecules that pass out of the body in the urine.
It sounded like a no-brainer, so I agreed, and my five-week course of treatment started a few weeks later, in december 2017. about a month before, the doctors injected the gel while I was under sedation.
at the same time, they implanted three tiny gold pellets into the part of the prostate that needed to be treated — these are a target, showing up on X-rays during radiotherapy treatment so that doctors aim the beam in the correct place. The whole process took no more than 30 minutes and was completely painless.
My radiotherapy finished in February, and although I’ll be on hormone-suppressing drugs and tamoxifen for another few months, my cancer appears to have gone.
My last psa test showed it was down to 0.2 — compared with 7.3 when I was diagnosed.
What’s more, there has been no sign of nasty side-effects from the radiotherapy, so it looks like the gel has done its job. I’m back to playing golf and enjoying life.
THE SPECIALIST Dr CIARAN FAIRMICHAEL is a cancer researcher at Belfast City Hospital.
RADIOTHERAPY is very effective in the treatment of prostate cancer. But targeting the beams so they hit only cancerous tissue can be difficult, as the prostate is so closely situated to several other vital organs. as a result, about one in 20 men having radiotherapy is left with long-term damage to the rectum.
In late 2016, we began a clinical trial involving 26 men to see if inserting a gel implant — called spaceoar (oar stands for ‘organs at risk’) — could reduce the collateral damage from radiotherapy by physically creating a space between the prostate and the rectum.
The patients in our trial all have locally advanced prostate cancer, which is where the cancerous cells have spread within the prostate but not migrated to other organs — the gel wouldn’t work for patients with more advanced disease as they would need to have the prostate surgically removed.
We implant the gel about a month before the radiotherapy begins. The patient is sedated and two vials are prepared, one containing a dry powder and the other a sterile salt water-based solution which, when mixed together, form a firm, but pliable, cigar-shaped gel (made from a type of flexible plastic called polyethylene glycol).
The contents are then passed through a 6in needle that has been inserted through the perineum, the area of tissue between the genitals and the back passage, until it reaches the tiny space between the prostate and rectum.
as the gel is released into this space, it immediately spreads to about 2.5cm in length and 1cm wide, prising the two organs apart. It increases the gap from only about 1mm to well over 1cm — a ten-fold increase or more, which is a big difference.
at the same time, we implant three tiny gold pellets into the part of the prostate that needs to be treated.
The pellets act as a target, showing up on X-rays during radiotherapy treatment so that doctors can be sure they are aiming the highenergy beam at the right place.
The reason for implanting both the gel and the pellets so far ahead of treatment — a procedure which takes less than half an hour — is to allow time for the implant to settle into position and for us to carry out scans to identify exactly where the gold pellets lie so that radiotherapy can be accurately planned. once this has been done, radiotherapy can start.
We are trialling shorter, highdose treatments that are just as effective as conventional longer, lower-dose regimens but much more convenient for patients. so instead of attending hospital five days a week for eight weeks of lower-dose radiotherapy, our prostate cancer patients are given a higher dose just once a week for five weeks.
With these higher doses, it’s even more important we aim them precisely at the cancerous tissue — that’s why the gel could be crucial.
The results of our trial will not be available until the end of the year, or 2019, but earlier studies have found the spaceoar gel — which has been approved for use by the National Institute for health and care excellence — reduces the rate of adverse effects involving the rectum from one in 20 men to about one in a 100.
The gel is available privately and on the Nhs, but not yet widely. as it’s fairly new in the UK we don’t have long-term results, but more than 10,000 men around the world have been treated with it, with promising results.
some studies suggest the gel can help not just with bowel function, but with ensuring men retain sexual function, which is sometimes reduced due to radiotherapy affecting nerves that control erections.
THE SpaceOAR procedure costs around £4,500.