The HER2 2013 guidelines from CAP/ASCO apply to all IHC and FISH methodologies.
Excisional specimens should be fixed in 10% neutral buffered formalin (NBF) for 6 – 72 hours
- If HER2 FISH results are negative, and the fixation time is known to be longer or shorter, this should be noted.
- If alternative fixative is used, the fixative must be validated against results for the same specimens fixed in 10% NBF.
- If an alternative fixative is used, the laboratory's director is responsible for test performance.