In the patient report, there are several necessary components per the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) guidelines.
The specimen fixative type, the time to fixation, and duration of fixation are important pieces of information for the report. Often, the time of fixation may not be known, but the duration of fixation can be ascertained from the histology department.
The methodology used for the assay should be recorded in the report, including:
- The probe identification and the number of observers
- The number of cells counted
- The average number of her2/neu signals per cell
- The average number of centromere 17 signals per cell
For some FISH assays, the ratio is generally given as the number of genes of interest/number of centromeres. For example:
- The ratio of HER2/neu/centromere 17 = 6/2 = 3.0
It is helpful to include the average signal number of the gene and the average signal number of the centromere. The report must contain an interpretation of the predominant FISH pattern observed. In our example, the HER2/neu gene is amplified.
Other components of a standard anatomic pathology report are required per the institution. It is helpful to include the surgical pathology accession number and the type and description of tissue assayed.