2005 April 15 Friday. 09:33.
        With time on my hands, my thoughts slide forward, in an evaluating way, to the topic of radiotherapy. This will be carried out, further down the track, at Auckland Hospital, with extremely modern high-tech machines which are at the cutting edge of the possible. However, when I received a briefing from my two radiographers last month, I had the briefing itself at Greenland Hospital.
        The briefing was very long and leisured, relaxed and honest: it seems that there is a debate in the medical world about exactly how to balance the use of chemotherapy and radiotherapy, and I'm left with the impression that any choice is going to involve an unavoidable element of speculation.
        That being said, it seems to be the case that:-
        (a) Assuming I have the radiotherapy as planned, the probability of the cancer coming back will drop, but
        (b) the radioactivity involves the possibility of damage, including brain damage (confusion and memory loss and so forth). Part of the bad news is that damage of one kind or another may not show up immediately. It might show up ten or fifteen years into the future.
        Nobody has been able to quantify the precise risk of brain damage for me, but I have seen some statistics relating to the outcome of a small experimental trial involving a particular combination of chemotherapy followed by radiotherapy.
        The disease treated in the experimental trial was the same as mine (non-Hodgkins lymphoma of the central nervous system) but the drug combination was different and the number of people involved was small. Given the slippery nature of the statistical situation, then, I can't legitimately expect these statistics to reliably predict my personal outcome.
        But, in the absence of anything else, it's these statistics that I'm personally using to get a kind of vague ballpark guide to the risks I'm facing in going through with radiotherapy.
        Of the (small) number of people in the experimental trial, twenty-two percent of those aged sixty or over suffered something severe enough to be described as "brain damage." For the group as a whole, the "brain damage" rate was fifteen percent.
        As I see it, then, though nobody has been able to precisely quantify the risks I'm running, it seems reasonable to presume that I have roughly an eighty-five percent chance of coming through the radiotherapy without a significant degree of cognitive deficit, which is good enough for me.
        Still, I do have a kind of looming awareness of the unknown consequences of radiotherapy, these including, possibly, cognitive deficit, damage to the endocrine function (since the pituitary gland gets irradiated), and, since the plan is to irradiate the back portion of each eye, possible eye damage.
        When it comes to chemotherapy, I have, for some reason, a confident feeling that my basic physical good health will help me deal with any chemical insult. But in the face of the prospect of the radiation, I don't have any such feeling of countervailing strength. Subjectively, I feel vulnerable to the imperial lordship of the radiation. It will do whatever it does and I will not be able to resist or modify it.
        Even without the upcoming radiotherapy, I've already soaked up quite a bit of radiation in the last twelve months, starting with a chest X-ray in Japan in May last year.
        Adding together what I had in Japan in 2004 and what I've subsequently had in New Zealand, inside of twelve months I've already had three CT scans (each of which involves a hefty belt of radiation), five chest X-rays and a gallium count (a procedure which involves an intravenous injection of a radioactive isotope).
        And I do believe that this stuff can come back and bite you.
        The above is the background to the radiotherapy poem which follows, a poem called, simply, RADIOTHERAPY:-