What should you know about IgG immunohistochemistry?

A laboratory applies an antibody-based stain to thin sections of preserved tissue. If the target is present, the stain creates a visible signal under a microscope. The pathologist compares the pattern with the tissue appearance and with other stains.

A positive IgG stain does not, by itself, name a cancer or prove that a condition is present. The meaning depends on which cells are stained, where the signal appears, how strong or widespread it is, and the findings from the rest of the pathology report.

Read the full pathology report with the clinician who requested the biopsy. Ask whether IgG staining was expected, whether additional markers were used, and whether the sample was adequate for interpretation.

Keep a copy of the report and note the tissue site and the date of sampling. Further review may involve another stain, laboratory testing, imaging, or discussion at a specialist meeting, depending on the diagnosis being considered.

Seek prompt advice for increasing pain, redness, warmth, discharge, fever, or bleeding at the biopsy site. Contact your care team quickly if you develop new breathing difficulty, facial swelling, or rapidly worsening symptoms while waiting for the report.

Ask what IgG was being investigated, where the stain appeared, and how it fits with the tissue pattern. Clarify whether the finding changes the diagnosis, whether more testing is needed, and when the complete report will be discussed.