Test Method


CPT Code

88342 x 1 or 88341 x 1 (qualitative)
88360 x 1 (quantitative, semi-quantitative - manual)

Stains / Test Description

MSH6 is a heterodimer of MSH2 and binds to DNA containing G/T mismatches. MLH-1 and MSH2 are involved in the DNA mismatch repair (MMR) process. Microsatellite instability (MSI) is an alteration of microsatellite repeats during DNA replication and is a hallmark of the inactivation of the MMR genes. These defects in MMR have been related to human carcinogenesis. Studies have shown the mutations in MSH-1, MSH2 and MSH6 genes contribute to the development of sporadic colorectal carcinoma. MSH6 antibody may be useful to aid in identifying the most probable gene responsible for the MSI.

Specimen Requirements

(1) H&E slide with formalin-fixed, paraffin-embedded (FFPE) tissue, fixed with 10% NBF.
One (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4 microns) for each test/antibody ordered

Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.

Storage & Transport

Ship specimen same day (whenever possible) with refrigerated (not frozen) cold pack

Turnaround time

1-3 days depending on level of service

Level of Service

Global (with interpretation)
Slide Only (glass slides only)
Web-Enabled (glass and digital images through eCSI portal)