TP53 IHC (aberrant p53 expression pattern)
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BIO-TP53-IHC |
|---|---|
| Type | Biomarker |
| Aliases | TP53 aberrant expressionaberrant p53 stainingp53 IHCp53 immunohistochemistryp53-abnormal by IHC |
| Status | reviewed 2026-05-05 | pending_clinical_signoff |
| Diseases | None declared |
| Sources | SRC-ESMO-ESGO-ESTRO-ENDOMETRIAL-2023 SRC-NCCN-UTERINE-2025 |
Biomarker Facts
| Biomarker type | protein_expression_ihc |
|---|---|
| Mutation details | {"gene_id_ncbi": 7157, "gene_symbol": "TP53", "note": "IHC-based surrogate for TP53 mutation. Two aberrant patterns recognized: (1) Diffuse strong positivity: >80% of tumor nuclei with strong (3+) staining — indicates gain-of-function or dominant-negative TP53 point mutation. (2) Null/complete absence: 0% staining with internal positive controls intact — indicates truncating/nonsense mutation or large deletion (loss-of-function). Wild-type pattern = patchy/focal heterogeneous staining (10-70% o... |
| Measurement | MethodIHC on FFPE biopsy or resection specimen. Anti-p53 antibody (clone DO-7 or BP53-12 — most validated). Scoring per TransPORTEC criteria: - Diffuse strong (abnormal): >80% cells, 3+ intensity (uniform nuclear) - Null (abnormal): 0% staining with verified internal control positivity - Wild-type (normal): focal / patchy, 1-2+ intensity Pathologist sign-out must explicitly distinguish wild-type from null pattern. |
| Related biomarkers | BIO-TP53-MUTATION BIO-DMMR-IHC BIO-MSI-STATUS BIO-POLE |
Notes
Critical biomarker for endometrial cancer molecular subclassification (WHO 2020 / FIGO 2023 / ESMO 2023). p53-abn endometrial cancers behave like HGSOC and require aggressive adjuvant treatment regardless of stage. IHC is the preferred practical method over sequencing alone because: (1) faster TAT, (2) cheaper, (3) handles the full spectrum of TP53 alterations (missense, nonsense, splicing). However, sequencing is needed for tumors with discordant IHC (equivocal pattern) or when IHC controls are suboptimal.
Used By
Actionability
BMA-TP53-IHC-ENDOMETRIAL- p53-aberrant (p53-abn) endometrial carcinoma defines the highest-risk molecular subgroup...
Biomarker
BIO-ATRX-MUTATION- ATRX mutation / ATRX loss (IHC)