Radioactive plaque

It crossed my mind some time ago to write a blog post called ‘Ten good things about having a child with eye cancer.’ Ten silver linings of an undeniably dark cloud. I’m not actually sure I could get to ten, but one of the things that would be up there is how much of Asa’s childhood we've had the opportunity to see (more than most parents, whose children can be safely packed away to a childminder or nursery while parents get on with making a living). Another would be the awareness that the fight against the disease has given us of the gifts of life and sight, which many people can take for granted.

The downsides are all too clear, of course. The misery of having poisons infused into your child’s bloodstream; the fear we felt, during chemo, of some infection snatching Asa’s life away; the repeated exams under general anaesthetic (more than 45 so far, since diagnosis); the sore, red eyes after exams, and the rigmarole of coaxing him to let us put stinging drops in them to control the swelling. The struggle to find the right words to explain to him, as he grows in awareness, why it is we submit him to these things. And the challenge of relating what we’re going through to others, who don’t know this disease (Why should they?) -- and why it is that, after more than 3 years of treatment, we still can’t give a simple answer to the question, “What's the prognosis?”

Asa at 4 months (approx 6 months before diagnosis), and today

A friend remarked recently that given all we’ve been through, we must have built up a certain toughness. Indeed we have; but there are still some areas of vulnerability. Sometimes small things can knock us sideways, like the difference between a four-week and five-week interval between EUAs. Usually the interval has been three or four weeks, and while you might think a longer interval would be better (More time away from hospital!), the extra week can feel like a long time, and your mind turns to wondering whether the tumours might be growing out of control as the clock ticks.

Another thing that tests us is coming to terms with new kinds of treatment. On the principle of “better the devil you know”, we come to feel comfortable with treatments Asa’s received in the past (particularly cryo and laser therapy, which he’s had lots of), and we get anxious about new ones. But when a relapse occurs that can't be treated effectively with methods that the doctors have used in the past, it’s inevitable that we have to consider new options.

Asa receiving an award from the Childhood Eye Cancer Trust, in recognition of his bravery. Hackney Farm, March 2015.

 

Last month Asa had a relapse in a part of his eye that's dangerously close to the ciliary body -- a structure that can serve as a conduit for tumour cells to travel outside the eye. Left unchecked, this could lead to the cancer colonising new parts of the body, and becoming a threat not just to his sight but to his life.

Radiotherapy

 

The treatment that the doctors have recommended on this occasion is radioactive plaque -- a piece of radioactive material inserted into the eye (stitched onto the surface of the eyeball) and left there for about a day and a half, to do its work. This approach was suggested to us a few months ago, as something that might be necessary if certain areas of activity didn’t respond to cryo. But only recently did the doctors make a forceful case for doing it now.

For almost as long as we've known about radiotherapy as a treatment for eye cancer, we've been scared of it. Back in 2013, a recommendation that Asa undergo external beam radiotherapy (EBRT) prompted us to look at the medical literature on this treatment, its rates of success and complications. What did we find? EBRT can be said quite unequivocally to be effective in treating tumours in the eye. But it’s also associated with increased risks of later life cancers -- particularly sarcomas in areas of the body that are exposed to collateral damage from the radiation beam, such as the bridge of the nose, or parts of the eye socket. These “secondary cancers” are very difficult to treat, and can be fatal. Which puts EBRT in the category of treatments that can cure the disease but risk killing the patient in the process (or at least reducing lifespan considerably).

Radioactive plaque definitely does not belong in this category. The radioactive substance that’s been recommended for Asa (ruthenium isotope 106) has a very sharp tail-off, and shouldn’t penetrate beyond a few millimeters into the eye. The radioactive material is enclosed in a metal case (thicker on one side than the other, so as to shield neighbouring structures), and is applied flush with the area of the eye that needs treating. All this serves to minimize exposure of surrounding tissue to radiation.

 

We've come around, in the last few weeks, to accepting that this is the best treatment available. But it’s still stressful. We ruminate on whether the treatment will work. Will the tumours in the right eye finally stop growing? Will there be side effects beyond the inevitable swelling and soreness? In September, when Asa starts primary school, will he still have the vision he has now? We can’t know the answers to these questions. We just have to wait and see, and hope and pray. 

This much we do know. Tomorrow morning Asa will go into the operating theatre at Birmingham Children's Hospital. He’ll sit on my lap or his mum’s to receive the anaesthetic gas through a face-mask, and we’ll tell him a bedtime story as he drifts off. We’ll likely be reunited with him around noon, by which time he’ll have had the plaque inserted, and from then on he’ll be confined to a side-room for the rest of the day and night, and for most of the following day, until they take the plaque out again in the evening. In the interim, we have to make the best we can of the time. Fill it with as much humour and distraction -- and joy, and love -- as we can.