Oestrogen receptor, progesterone receptor and HER2 results drive breast cancer treatment, and the commonest reason they come out wrong is not the stain but what happened to the tissue before it reached the block. Pre-analytic control is the pathologist's lever here.
Keep cold ischaemia time — from removal to fixation — to an hour or less, and fix in 10% neutral buffered formalin for the recommended window of roughly 6 to 72 hours. Too little fixation or a long delay before fixation degrades antigenicity and can turn a true positive into a false negative.
Record the ischaemia and fixation times with the specimen, and reflex equivocal HER2 immunohistochemistry to in situ hybridisation. In laboratories with variable transport and fixation, these simple controls prevent discordant results that change a patient's treatment.
- Keep cold ischaemia time to one hour or less from removal to fixation.
- Fix in 10% neutral buffered formalin for roughly 6 to 72 hours.
- Record ischaemia and fixation times with the specimen.
- Reflex equivocal HER2 immunohistochemistry to in situ hybridisation.
Why it matters
Poor fixation and long cold-ischaemia times are a leading, avoidable cause of false-negative hormone-receptor and HER2 results that misdirect treatment.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for pathology, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free