As a quick recap, I have PD-L1 positive, triple negative breast cancer, metastasised to my liver. I have been being treated with an immunotherapy drug called Pembrolizumab. In layman’s terms, our immune systems have an ability to deal with cells showing signs of DNA damage, and the mechanism for this involves ‘programmed death’. Our bodies need to stop key organs being unnecessarily damaged by the immune system, so our bodies also have an ability to work against this mechanism by putting up an invisibility cloak around key organs. My nasty, pesky cancer uses this exact same approach to hide away from my immune system. Like having Harry Potter’s invisibility cloak wrapped round all my cancerous cells, leaving them to merrily multiply despite their damaged DNA.
Pembrolizumab is a checkpoint inhibitor that breaks this cloaking effect. It makes my cancer visible to my immune system. It also makes all my key organs that are normally protected from adverse harm visible to my immune system. In the fact sheets for Pembrolizumab you find a long list of things that can go wrong. The most serious ones are rare occurrences.
I walked into this with my eyes open. Very well researched, very aware of the risk, plus also the benefit of a possible durable remission. I had no other option of something that could do this, just life extenders with various quality / quantity of life trade offs. So it was clearly a risk worth taking. And the treatment is working on the cancer.
However, I have drawn the risk short straw big time. Last Tuesday I had routine bloods tested ahead of normal treatment the following day. I was asymptomatic other than a bit thirsty. I had just returned from France where it has been very hot. At 5pm I received a call to be admitted immediately to hospital. Creatinine level over over 350, my normal baseline between 60-80.
As I immediately suspected, other causes were swiftly ruled out and the working hypothesis was I was suffering a grade 3 adverse immune event on my kidneys and thyroid (thyroid blood tests also markedly changed). The thyroid function is permanently lost but can be replaced with thyroxine. The kidneys are a whole different matter. I have nephritis. Immediately put onto very high dose steroids, creatinine reduced to about 250 at which it is currently stable but not reducing. I am at the maximum steroid level I can have.
it’s now a knife edge to see whether the kidneys can recover and the steroids can be weaned down. I have a maximum 10 weeks on high dose steroids. The pembro last went in my system 6 weeks ago and has a half life of about 6 months, so it will be some time before Harry Potter’s invisibility cloak can do its thing again. No one can answer whether the attack will wane of its own accord or continue until the rebuilt shield stops it. Living on high dose steroids for 10 weeks has potentially life changing consequences, as well as the obvious immediate effects in terms of sleep, jitteriness etc. If creatinine levels go up again I am basically stuffed, and they will go up if we get to 10 weeks and I haven’t been able to bring them down alongside a steroid taper. My immune system may start off on some fresh targets too. Plus I am vulnerable to a whole host of other things going on,
Currently lucid and at home. There was no point keeping me in as not much can be done other than fluids and steroids. I had 3 days inpatient, on IV fluids, IV steroids. 3 days home returning daily as outpatient for IV fluids and steroids. We are now in a phase of seeing what happens with 60 mg of prednisone tablet steroids per day at home, large amounts of water in, measuring in/outs, 3 times weekly visits for blood tests. I took up over an hour of my consultant’s time yesterday on how best to try to manage this with minimum life altering consequences, assuming I can survive it. A real difficulty getting them to stop worrying about what lines of treatment they may be able to give me in the future, when all I want them to do is focus on this severity 1 incident.
Next post will be about the joys of my hospital stay, when I feel up to it.
I don’t want anyone sad, or praying for me, or any of that kind of stuff. There’s one perhaps narrow route through this where I am laughing about my adverse event over Christmas and happily in remission. Otherwise I took my chances knowingly and drew the very short straw. Frankly I would rather go quickly through this, than the grizzly end I would have faced in the next year or so if I hadn’t tried it. Cancer sucks. Sometimes the treatment is even worse. I am sure Merck will not be happy to get another yellow card report on their blockbuster drug.
