Half of us will have cancer at some time in our lives. By far the most common is prostate cancer for men and breast cancer for women. These exceed lung, bowel, ovary and testicular cancers by a factor of 2 or more.
I never asked for a PSA (Prostate-Specific Antigen) test, but I got one anyway when my GP checked me over one day. The result was high, so did I mind if he did a rectal examination. I said it would be OK if he promised not to enjoy it any more than I would.
‘You’ve got cancer there. It’s a decent-sized lump but still in the prostate, hasn’t spread. We’ll zap it with radiotherapy; surgery is not a sensible option. It’s 99% curable for five years, and you might die of something else in the meantime.’ My doctor is a straight-talking man, I was pleased not to be offered surgery. When I was a junior doctor, I assisted in prostatectomy operations and looked after the patients afterwards. I was called up most nights to deal with blocked catheters or excessive bleeding. Later on, many of the men suffered urinary infections and other complications.
Luckily for those living in Hampshire, there are six LINAC (linear accelerator) machines available, and another one being installed. These machines produce a beam of electrons travelling near the speed of light, accelerated by some 10 million volts. Electrons have a mass so cannot reach the speed of light, but they get close to it. The electron beam is focused onto a tungsten target whose atoms emit X-rays when hit by the electrons. X-rays are photons, which have no mass and a very short wavelength so they carry a lot of energy at the speed of light.
See the video:
The X-ray beam is wide and must be collimated to a suitable width and shape for hitting the prostate and nothing else. The prostate is the size of a walnut and wedged between the bladder and rectum, deep down inside. How do I get my miserable prostate at the centre of a multi-million pound, 10 ton, 10 megavolt, LINAC so that the machine can rotate around it?
Before starting treatment, I had an implant similar to those favoured by certain ladies to enhance their buttocks. In my case, the implant was placed between the prostate and rectum to separate the two. The spread of radiation to the rectum can revolutionise your bowel habit, but not in a friendly way. Then I had an MRI scan to show exactly where everything is. Three tattoo spots were put on my skin as fiducial points.
Now I could be positioned in the LINAC. I lie on a table that moves up and down, back and forth, until reference laser beams coincide. Then a CT scan is done and final positioning adjusted. There are essential pre-conditions; my bowels must be empty, even of gas, and my bladder full, but not so full that I can’t hang on for the duration of the treatment. You cannot cheat, the scan shows what is in your bowel and bladder and you will be sent to the back of the queue if things are not right.
Treatment times are precise, 09.57 hrs, for example. One must arrive at 09.27 at the latest, empty the bladder and drink 3 glasses of water before 09.37. There are half a dozen of us there, at various stages of hydration, and we move through the system at 12-minute intervals.
Consternation arose one morning when the staff announced a 20-minute delay. Legs were crossed, and the most hydrated man at the front of the queue could not hang on, neither could the next. The third man drank up on schedule and went in. The others joined the back of the queue. Synchronising the bowel, bladder, and the machine is a trick we must learn.
When called, we go into a changing room and remove our trousers and then walk to the machine in our underpants. Those awful shroud-like garments that leave your backside hanging out are provided but eschewed by us. The discerning, fashion-conscious gent will colour co-ordinate his shirttails with his underpants. An interesting pair of socks is appreciated by the radiotherapists who fix our feet on a footboard and shuffle the pelvis into position.
Then you are alone with the machine, which whirs, buzzes, squeaks and rotates around. Once round for the MRI, then re-positioning, then another round for the X-rays to do their stuff. You feel nothing but the whole room is filled with radiation, and the staff watch you from a bunker. The room itself is a blockhouse with thick walls lined with barium plaster to contain the X-rays. I am beginning to doze when someone appears.
‘That’s it, all done. See you tomorrow.’
I have felt nothing, but after the first half dozen of my 20 treatments, I know something is happening because there are changes ‘down there’.
While lying there I thought of Aleksandr Solzhenitsyn’s Cancer Ward. The story is a parody of his country, Russia. The Soviet government is a growing cancer within it. Could a country be a healthy place to live if it had, deep within it, a cancer of corruption like the Soviet state? A rhetorical question, but does it apply to us? I thought about recent events while the machine rotated; unprepared for a pandemic, proroguing parliament, denying COVID-19, dodgy contracts for PPE, expensive wallpaper, strange building contracts, oh dear. Not as brutal as the Gulag Archipelago or Stalin’s purges but nothing to be proud of.
When the treatment is complete, I will be considered cured for the next 5 years. That’s not a bad deal as only 60% of men of my age can expect to live 5 years. I will probably succumb to some other disease before the cancer returns if it is ever going to.
For the Techies
There are about 250 LINAC machines in the UK. The first LINAC was installed in the Royal Marsden Hospital in 1952. The kind of treatment I am having would cost about $30,000 in the USA so let’s hear it for the NHS, who do not even charge me for parking.
LINAC machines are produced by Elektra, a Swedish company founded in 1972 by a neurosurgeon, Lars Leksell. Early in my career, I came across Leksell and his supervisor, Nobel prizewinner Ragnar Granit, at the Karolinska Institute in Stockholm. Our interest at that time was precision control of muscles. Interesting that his name crops up again at the end of things.
Using a high energy electron beam and a tungsten target, the machine produces a hard x-ray of wavelength 0.0184 nanometres and carrying 67 kilo electron volts energy. The energy deposited in the tissue is measured in grays. 1 gray is equivalent to 1 Joule per kilogram of tissue. My course delivers 60 gray in 20 sessions. Sixty grays may not sound a lot of energy but it is very intense energy focused on the cancer cells which are ruptured.
My last treatment was a month ago now. Happily all those functions ‘down there’ have returned to normal. My PSA is hardly registering on the scale and I’m good to go.