POLE germline pathogenic variants in the exonuclease (proofreading) domain cause polymera...
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BMA-POLE-GERMLINE-POLYMERASE-PROOFREADING |
|---|---|
| Type | Actionability |
| Status | reviewed 2026-05-18 | pending_clinical_signoff | actionability review required |
| Diseases | DIS-CRC |
| Sources | SRC-NCCN-GENETIC-FAMILIAL-CRC-2025 |
Actionability Facts
| Biomarker | BIO-POLE-GERMLINE |
|---|---|
| Variant | POLE germline exonuclease-domain pathogenic (PPAP — polymerase proofreading–associated polyposis) |
| Disease | DIS-CRC |
| ESCAT tier | IIA |
| Recommended combinations | colonoscopy q1-2y starting age 20-25 with polypectomy, EGD q3y from age 30, endometrial sampling + TVUS q1-2y from age 30-35 (women), annual urinalysis from age 30, for POLE-mutant advanced CRC / endometrial: pembrolizumab 200 mg q3w — high response rate in ultramutator setting (NCCN Category 1 for TMB-H or MSI-H), cascade testing to first-degree relatives; specific to exonuclease-domain variants (Pro286Arg, Val411Leu most common) |
| Evidence summary | POLE germline pathogenic variants in the exonuclease (proofreading) domain cause polymerase proofreading–associated polyposis (PPAP) — characterized by attenuated/oligo-polyposis (typically <100 adenomas), early-onset colorectal cancer, elevated endometrial cancer risk in women, and characteristic ultramutator tumor phenotype (TMB >100 mut/Mb) with potential immunotherapy responsiveness. Confirmed-carrier surveillance protocol (Lynch-like; per NCCN Genetic/Familial CRC 2025): colonoscopy q1-2y starting age 20-25, EGD q3y from age 30, endometrial sampling + TVUS q1-2y from age 30-35 in women, urinalysis annual from 30 (overlap with Lynch organ spectrum). The ultramutator phenotype in POLE-mutant tumors predicts immunotherapy benefit (high TMB) — pembrolizumab is FDA- approved for TMB-high (≥10 mut/Mb) advanced solid tumors regardless of tissue; POLE-mutant CRC and endometrial benefit appears substantial in small series. ESCAT IIA (predisposition + tumor-phenotype actionability). |
Notes
STUB — Wave A+B germline expansion. Linked Indication: IND-LYNCH-CARRIER- SURVEILLANCE used as closest-fit (POLE-specific Indication does not yet exist; PPAP overlaps Lynch surveillance for CRC + endometrial). Note that IND-ENDOMETRIAL-STAGE-I-POLE-OBSERVATION exists for the somatic-POLE endometrial-treatment context — distinct from germline-carrier surveillance handled here. Two-Clinical-Co-Lead signoff queued. Variant classification matters: only exonuclease-domain variants (Pro286Arg, Val411Leu, Ser297Phe) drive PPAP — non-exonuclease variants are usually uncertain significance.
Used By
No reverse references found in the YAML corpus.