What should you know about AFP immunohistochemistry?

The finding is interpreted as one part of the biopsy assessment. AFP staining alone cannot confirm where a tumour began or settle the diagnosis.

An antibody is applied to prepared tissue to look for alpha-fetoprotein within the sampled cells. If the target is detected, the pathologist records the cellular location and pattern of staining and compares it with the shape and arrangement of the cells.

AFP can be expressed by some liver tumours and some germ cell tumours, but expression is not exclusive to a single diagnosis. Some tumours in these groups may show little or no staining. For that reason, the result is weighed with other tissue markers, imaging, clinical details and, when appropriate, a blood AFP test.

Focus on the final diagnosis section and the pathologist's integrated comment. A positive AFP stain may support a proposed tumour type when the microscopic features and other markers fit; a negative stain may make that interpretation less supportive without necessarily excluding it.

Your clinician may compare the tissue result with the site of the mass, scans and blood tests. If findings conflict or the sample is limited, possible next steps include review by a specialist pathologist, more laboratory stains or collection of additional tissue. Treatment decisions should follow the combined assessment.

The AFP stain is performed on tissue outside your body, so the stain itself cannot make you unwell. Contact the treating team if the biopsy result has arrived without a follow-up plan, if different reports appear to disagree or if symptoms are worsening while you wait for clarification.

After a biopsy, seek prompt advice for fever, increasing pain, spreading redness, drainage or persistent bleeding from the procedure site. Get urgent help for severe breathing difficulty, fainting or heavy bleeding rather than waiting for a pathology appointment.

Ask whether AFP staining was present, which cells showed it, and which diagnosis the full marker pattern supports. Clarify whether the tissue AFP result matches any blood AFP measurement, whether the sample was sufficient and whether further pathology review would change management.