The Adventures of the Radioactive Pharmacist (volume 1)

Okay; the title strays fairly widely into clickbait territory. The truth is that most forms of radiation therapy - and specifically the form that I am getting - do not mean radioactive therapy.

Sorry Morgan - no radioactive pee. Not now, not ever.

While there are some cancers that are treated with internal radiation (otherwise known as brachytherapy), I am undergoing external beam radiation therapy. A large machine called a linac (for linear accelerator) directs a beam of particles - protons in my case - into my pelvis to kill off any remaining cancer cells that might have been too small to see or appear on CT scan. Radioactivity would persist, only decreasing as it decays over time (often years or decades); the sort of radiation that I am getting stops the moment they turn off the machine. It's more like turning off a light switch; if I were being exposed to radioactivity it would still be bouncing around the room once my therapy was over.

So... what is it like getting radiation therapy?

Obviously I can only answer from the perspective of my own therapy so please know that my experience is not necessarily the experience of everyone who undergoes radiotherapy. But because several of the people that matter in my life seemed a little... freaked out?... when they found out that I am undergoing radiation therapy I thought it would be useful to share what is actually involved.

Simulation.

The first step of my radiation therapy was simulation. I wouldn't actually receive any radiation aside from the X-Rays during the CT scan, but it would provide a detailed picture of my anatomy to the radiation oncologist to plan my therapy.

Simulation starts an hour before I am scheduled. I have to empty my bladder, then drink 750 mL of water within 15 minutes to fill it to a predetermined level. Filling the bladder for my radiotherapy serves two purposes; it 'pushes' the small intestine up and out of the pelvis so that it is not exposed to radiation, and it also stretches the bladder so that there are no wrinkles that can absorb more radiation.

The goal of my radiation therapy is to get the maximum amount of radiation deposited on my rectum and sigmoid colon and the minimum anywhere else. By having a consistently full bladder, I can avoid adverse effects while getting the most benefit in terms of prevention of my cancer recurring.

My bladder fills as I drive (or am driven) to the cancer treatment centre. The radiation therapist takes my picture, explaining that it will be attached to my electronic record and seen by everyone involved in my therapy - an added layer of security, in addition to checking my name and birthdate every time they see me. I lay down on a CT bed (a very fanciful term for a solid slab of material underneath me) as she and another radiation therapist put three stickers on my skin (one on each hip and one on my lower abdomen) over red Xs that they have very carefully measured out from specific points on my hip bones. They spend a few minutes shifting me ever-so-slightly this way and that, flexing my knees subtly, and tilting my feet one way or the other. They are gentle and caring but efficient and professional - like everyone at the treatment centre - and they talk to me constantly throughout the process. They leave the room to complete the CT, showing not only my anatomy but more importantly the external markers that they have placed on my skin and a special little surprise - a wire in my anus.

Not surprisingly, the radiation oncologist needs to know exactly where my anus is to plan my therapy. Oh well; it's not the greatest indignity I have nor will suffer in life.

These four points - a spot below my belly button, one on each hip, and my anus - will form two axes through my pelvis. Because it's important that my radiation is delivered exactly the same way each time, after my scan these markers were replaced with the tiniest tattoos you have ever seen.

Seriously. I don't think I could have made a dot as small as them if I had even tried. So despite my joking on the subject, there was never any chance that I was going to get a butterfly on each hip.

My tattoos done, my radiation oncologist uses my CT scan to establish the target for the radiation that I am to receive. I am told that the two axes that were identified during simulation will be used to build a 3D model of my colon for the linac to follow. I honestly have no idea how the radiation oncologists this but I doubt that it involved robes, pointy hats, or a wand. It might as well be magic, though - there will be no obvious sign of my radiation therapy.

That's the subject of the next section.

Radiation. Every day except weekends and holidays...

There are six linacs at my local cancer treatment centre. Some are better suited to certain types of radiation delivery; I have been assigned to the Spruce suite but apparently I can be treated in Cedar as well. 

Yes; they are all named after trees. This is the West Coast, after all.

My preparation for radiotherapy begins an hour before my appointment. - just like it did for my simulation. I empty my bladder, then drink 750 mL of water within 15 minutes and make my way to the treatment centre. I don't need to check in or anything; instead I place my little yellow appointment booklet in a tray and sit in the waiting area. I don't need to wait for too long - fortunate, given that my bladder is now pretty full although not painfully so - before one of the radiation therapists calls me.

"John? Are you ready?"

During my first session the radiation therapists showed me their console at their station. A picture of me - the one taken during my simulation - is on the screen along with two CT views of my pelvis. The radiation therapist explained that they start out by taking X-rays of my pelvis along the same two axes each time and may have to adjust the bed of the linac so that my pelvis aligns precisely with the simulation image. She also explains that they will be able to see me and hear me clearly during each session so if I need anything just to wave or call and they will be able to respond. 

I'm sure they would go through this orientation each time I show up for radiotherapy, but I pretty much have the idea based on this first explanation. 

I walk into the radiotherapy suite with the radiation therapist and put my bag on a counter along the side of the room. There are more coat hooks on the wall than I think any single person has a reason to use; I hang my jacket on one of them and look up at the two large monitors on the wall. My picture is up there, along with my name and birthdate and which session I am having. There is also a lot of other information that I presume means something to the radiation therapists but is just random numbers and letters from my perspective. The words NO MOVE and FULL BLADDER appear in bold letters, at least four times the size of any other information on the screen. 

It must be important. One of the radiation therapists confirms with me every time that my bladder is full. We have time for a bit of a chat, as well as time for me to read all of the information on the two  screens as I walk across the HUGE room to the linac bed.

It really is huge - probably at least 7 metres on each side. The linac is a big machine, but it only takes up a small portion of the dance floor. The room is painted in soothing colours and has good but subdued lighting that makes it all seem very soothing. I lie down on the 'bed' (just as fancifully named; putting a sheet on a pane of glass does not make it a bed!). The radiation therapist apologizes because these beds are narrow - just barely as wide as I am at the shoulders. 

Oh well - at least my pelvis fits on the bed, and that's the important part.

I lower my pants and underwear to my thighs as one of the radiation holds a small sheet (okay, a pillowcase) over my genitals. They need to see the tattoos but have no interest in seeing any other part of my middle-aged body, and I'm okay with that. I'm not overly modest, but I know I don't look my most dignified with my pants and underwear around my thighs. I lay down and they arrange the 'sheet' carefully so they can see all three of my tiny little tattoo dots.

There are precise lasers built into the ceiling and two side walls of the room that beam three thin red crossed lines onto my skin. The radiation therapists tilt my feet in the foam holder and adjust the bolster under my knees and use the sheet beneath me to adjust my body so that the red crosshairs are centred on my tattoos and a red line goes up the middle of my belly, chest, and face. They work quickly and collaboratively, lining me up in about a minute before telling me they are going out to their console.

I am alone in the room for another minute. It is relatively quiet, and aside from the fact that there is a very hard and small bed supporting me I am comfortable.

The first part of the session involves taking the lateral (side-to-side) and AP (Anterio-Posterior, or front-to-back) X-Rays to make sure my pelvis is exactly where it should be. Two panels whir out on articulated arms beside me and I hear the sound of a high-voltage relay clicking as the lateral X-Ray is taken. The C-arm of the linac rotates 90 degrees so that the X-Ray panels are above and beneath me and there is another click of a relay as the second AP X-Ray is taken.

I am alone with my thoughts for a moment as the therapists check the X-Rays against the original views from my simulation CT. Sometimes they adjust the table slightly, shifting me forward or back or to one side or the other to line me up with where the linac expects me to be. I know everything is as it should be when the C-arm rotates another 90 degrees clockwise, putting the emitter head underneath my lower back. Another relay clicks and I hear a buzzing sound for fifteen seconds.

I feel nothing. No heat, no tingling, no static. Nothing. 

The C-arm rotates back 90 degrees counter-clockwise, the emitter now pointing at my left hip. I hear another relay click and the same buzzing I heard when it was beneath me; for about ten seconds the head stays where it is, then it continues to buzz as it slowly rotates counter-clockwise 180 degrees before stopping and buzzing for ten seconds into my right hip. I can't be certain, but my guess is about thirty seconds of radiation in this second part of the session.

Forty-five seconds total.

"All done!"

The radiation technologist is cheerful as she comes back in the room and lowers the table, pulling it out from under the linac. I pull my pants and underwear up and get off the table, retrieve my jacket and bag and, most importantly, my appointment card.

I'm going to need it tomorrow. For my next session.

Adverse effects

I'd be lying if I said there were no noticeable effects of radiotherapy. While I can't notice the effects when I am receiving my radiation, I do notice it a few hours later. I get tired - not actually sleepy, but tired. My eyes feel heavy, every movement requires more effort than it did earlier. Even my thoughts are sluggish, like I'm not quite awake.

The Coles notes version of how radiotherapy works: it kills off cells, but it kills off tumour cells more readily than healthy cells. The radiation is targeted in my rectum and sigmoid colon, which actually represents a pretty large surface area of tissue that is being almost killed off each day. I have to heal from that onslaught, and even though I can't feel it like I could a sunburn, the same healing has to happen. And that healing takes energy.

The other aspect of this is less delicate than being analogous to a sunburn. Blasting my descending and sigmoid colon and rectum with radiation leads to more water loss in stool, otherwise known as diarrhea. And that is no fun, no matter how you slice it. To make matters worse, the capecitabine that I am taking also causes diarrhea, so I am subject to a sort of double-whammy on each radiotherapy day. While I have noticed a change in the consistency of my stools, I am happy to report that so far I have not experienced any diarrhea.

Just like the colon, my bladder can become irritated from the radiation. The radiation can only get to my rectum and colon by passing through - or at least, very close to - my very full bladder so there are bound to be some effects from that. I could have some small amount of blood in my urine - which would not be surprising - and I am at an increased risk for urinary tract infections so I need to be aware of any changes in my urine or any pain in my pelvis or flank that could indicate a developing infection.

Not too surprisingly, I could also have some skin reaction where the radiation is being beamed through my skin. Redness, irritation, and even blisters and skin breakdown can occur, not unlike a bad sunburn. And just like my bladder, the radiation definitely has to travel through my skin to work on my rectum and colon so it is bound to experience at least some reaction to the radiation.

These adverse effects could get more pronounced as time goes on and are likely to persist for a few weeks after I am done radiotherapy. Another thing that could occur as time goes on is immunosuppression, both from the effect of the radiation on the bone marrow in my pelvis as well as from the chemotherapy that I am taking. My blood work is being monitored each week and if I have a significant decrease in my white blood cell lines, my oncologists will adjust the dose of both my radiation and chemotherapy. I need to be careful not to do anything that puts me at risk of infection and if I have any signs of an infection (fever of 38C, chills and rigors) I need to go to the hospital immediately to start on antibiotics. 

It's not likely that I will get any significant immunosuppression. But believe me, I take this potential

adverse effect seriously. I've already taken my temperature once because I felt chilled and unwell, but my temperature was 36.2C. I will still keep an eye on it - an ounce of prevention is worth a kiloton of cure in this case.

The other even more unlikely long-term adverse effect of radiotherapy is, ironically, to cause cancer. It's weird; after all, the whole reason that I am undergoing radiotherapy is to prevent cancer from regrowing so why would it cause cancers? Well, the answer is a bit enigmatic: it just can. The same damaging beam of protons that kills one form of cancer can trigger another if it hits just the right part of just the right cells. Bladder cancer and prostate cancer are the biggest concerns given where my radiation is being directed, but really anything in the area could be triggered to grow into more cancer. But if that happens, it will be years down the road and I will be closely followed for any early signs that this is happening.

And... how long am I going through this?

Every weekday for five weeks. And I'm already 20% done!

Closing thoughts...

Radiotherapy sounds terrifying. It's really, really not. The people at the treatment centre are amazing and I am being really closely monitored for any adverse effects. I have a small army of highly-trained professionals caring for me and watching for the first signs of toxicity, and if they occur they will make whatever changes are required to restore a reasonably normal life for me. 

I'm in good hands.

That said, nobody would want to go through what I am without a good reason. As I wrote about the adverse effects of radiotherapy and the minor assault on my dignity as I lay on a hard, narrow bed and have radiation beamed through my skin and bladder to kill off healthy cells in my rectum and colon just in case there are any unhealthy cells in the area that will regrow into a recurrence of my cancer in the future, I started to ask myself one simple question.

Why?

Because it's worth it - at least, in my opinion.

As relatively innocuous as radiotherapy is to receive, the risks of adverse effects are more than offset by the potential to avoid a recurrence of my cancer. And I want to lead a long and healthy life, enjoying this amazing world each day. So if that means that I have to put up with the inconvenience of five weeks of daily radiation, I will make that decision every single time.

Plus which, I now have three awesome new tattoos!

;-)