When a camera lens is focused on a particular object, light rays converge to a single point on the sensor (or film) in the back of the camera.  If the light rays don’t converge – perhaps because the lens is not focused properly – they produce a larger optical spot rather than a point.  This is the so-called circle of confusion.

The term implies that anything falling inside this spot will be imprecise, fuzzy, not quite what we expect.  We think we know what we are seeing but we can’t be sure.  Annie and I are sitting inside a circle of confusion right now.

We’re in Oxford for the 3-monthly oncology appointment.  We’re expecting that the diagnosis suggested by the thoracic consultant we saw a month ago – “there is no evidence to suggest the cancer has returned…” – would be confirmed.  But it can’t.  Not yet.

The consultant oncologist is busy so we see one of his colleagues, who describes himself as a professor of clinical oncology.  He’s very good; friendly and communicative – uses big words with the assumption that we will understand, rather than patronizing us.

He wonders why the scan I was supposed to have had in Oxford last week was cancelled.  We explain that I had one in MK a month ago and as the results had been sent through to the Churchill we were advised that the second one was not necessary.  He disappears for about 20 minutes.  He’s extremely apologetic.  It’s not on the system; “There’s been a breakdown in communications”.

He cannot confirm what we want, what we expect, to hear.  “Everything is pointing to radiation pneumonitis … your blood test is lovely … but it’s very difficult to tell the difference on a CT scan between radiation scarring and …” he hesitates for just a fraction and looks me straight in the eye “…. a tumour”.

He explains that radiation pneumonitis has an evolution of around 8 months.  So the timescale with the symptoms I’ve been experiencing seems to fit.   The blood test does not indicate cancer.  But he needs to see the scan.   I understand his caution; he reiterates the difficulty, if people don’t know what they’re looking for, of interpreting such a scan.

He confirms that radiation pneumonitis can lead to pulmonary fibrosis.  “That was explained to you at the time?”  No it wasn’t.  Not properly.  There was a sentence in the ‘side effects of radiotherapy’ handout about the possibility of developing pneumonitis.  It was Google that first led me to pulmonary fibrosis.

He comes up with a scheme to access and interpret the scan.  He requests an appointment in a week’s time.  But I don’t actually need to be present – the very fact of the appointment will ensure that the scan arrives and will be discussed by the oncology team.  And they will phone me with the results the same day.  If it is a tumour they’ll call me back in.  If not then I’ll have another X-ray in 3 months time.  He hands me the appointment request with a wry look;  “Try and explain this to the receptionists.”  In the meantime “get on the bike”.

On the way out I make the appointment; “you can have 11.00 or 11.30 – what would you prefer?”   I explain that it doesn’t really matter, as I’m not going to be here.  Mistake.  There is a queue forming behind me as I try and explain that this is all a ruse – it’s just a means of getting a scan electronically transferred from MK to Oxford.  I try again in a conspiratorial manner.  In the end I settle for 11.00.

As we walk to the car I ask Annie how she’s feeling:  “It’s not conclusive.  I’ll be happier next Thursday”.  We both think it’s radiation pneumonitis.  Our new best friend probably thinks so too.  I feel physically and mentally better than I did a month ago.  We can see a picture of life returning to normality – although it’s still fuzzy and imprecise.  Not quite there, but tantalizingly close.