A seventy-eight-year-old man arrived with intermittent fever, cough and breathlessness. CT showed lymph-node enlargement. Infection, malignancy and inflammatory disease all remained possible.
Cross wanted a confident answer from the PET scan.
Daniel refused.
"The pattern is suggestive, not specific."
"Patients do not come here for suggestive."
"They come here for accurate."
The eventual diagnosis was inflammatory rather than malignant.
Cross did not apologise.
He did, however, stop using certainty as a weapon for several weeks.
For Daniel, the case reinforced what Margaret's illness had already taught him: sophisticated imaging did not remove uncertainty. It organised it.
That became the central idea of his teaching.
Not that PET could see everything.
That no test should be asked to carry more truth than it contained.