IHC

PMS2

Identifies a DNA mismatch repair (MMR) protein involved in recruiting other repair factors to correct replication errors during cell division. Loss of PMS2 expression can indicate MLH1-related defects and is useful for detecting Lynch Syndrome–associated tumors, as well as sporadic colorectal and other cancers with microsatellite instability (MSI). PMS2 abnormalities account for a small but meaningful subset of colorectal cancers and are commonly seen in MSI-positive tumors.

Synonyms

PMS1 protein homologue 2

Full Description

Identifies a DNA mismatch repair (MMR) protein involved in recruiting other repair factors to correct replication errors during cell division. Loss of PMS2 expression can indicate MLH1-related defects and is useful for detecting Lynch Syndrome–associated tumors, as well as sporadic colorectal and other cancers with microsatellite instability (MSI). PMS2 abnormalities account for a small but meaningful subset of colorectal cancers and are commonly seen in MSI-positive tumors.

Methodology

IHC

Specimen Requirements

Tissue Block: Formalin-fixed, paraffin-embedded (FFPE) tumor block preferred. Unstained Slides: Recommended 2 charged slides per stain requested (minimum of 1 slide per stain), baked or unbaked. Fixation: Tissue must be fixed in 10% neutral buffered formalin for 6–72 hours.

Storage and Transportation

Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.

Turnaround Time

Global: 48 Hrs, Image Analysis (tech-only): 36 Hrs, Tech-Only (stain only): 24 Hrs

CPT Codes

88342x1 or 88341x1 (qualitative IHC) or 88360 (quantitative/semi-quantitative – manual) or 88361x1 (quantitative/semi-quantitative – computer assisted)