MSIHC - Overview: Microsatellite Instability (MSI)/Immunohistochemistry (IHC) Profile-Lynch/Hereditary Nonpolyposis Colorectal Cancer (HNPCC) Screen

Test Catalog

Test Name

Test ID: MSIHC    
Microsatellite Instability (MSI)/Immunohistochemistry (IHC) Profile-Lynch/Hereditary Nonpolyposis Colorectal Cancer (HNPCC) Screen

Useful For Suggests clinical disorders or settings where the test may be helpful

Assessment for defective mismatch repair (dMMR) to identify solid tumors that may respond to anti-PD-L1/PD-1 immunotherapy


Evaluation of colon tumor tissue for evidence of microsatellite instability to stratify prognosis


Identification of individuals at high risk for having hereditary nonpolyposis colorectal cancer (HNPCC)/Lynch syndrome

Genetics Test Information Provides information that may help with selection of the correct test or proper submission of the test request

Both microsatellite instability (MSI) and immunohistochemistry (IHC) testing of tumor tissue are performed to screen individuals for possible hereditary nonpolyposis colorectal cancer/Lynch syndrome, assess for microsatellite instability-high (MSI-H) or defective mismatch repair (dMMR) as a predictor of response to anti-PD-L1/PD-1 immunotherapy (eg, pembrolizumab), to aid in clinical decision making, and to stratify prognosis in colon cancer.

Additional Tests Lists test(s) that are always performed, at an additional charge, with the initial test(s)

Test IDReporting NameAvailable SeparatelyAlways Performed
MLH1IMLH-1, ImmunostainNo, (Bill Only)Yes
MSH2IMSH-2, ImmunostainNo, (Bill Only)Yes
MSH6IMSH-6, ImmunostainNo, (Bill Only)Yes
PMS2IPMS-2, ImmunostainNo, (Bill Only)Yes
SLIRVSlide Review in MGNo, (Bill Only)Yes

Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.

When this test is ordered, slide review, MLH1, MSH2, MSH6, and PMS2 stains will always be performed at an additional charge.


See Hereditary Nonpolyposis Colorectal Cancer Testing Algorithm.

Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test

Method Name A short description of the method used to perform the test

Microsatellite Instability (MSI): Polymerase Chain Reaction (PCR)/Immunohistochemistry

(PCR is utilized pursuant to a license agreement with Roche Molecular Systems, Inc.)

NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name

MSI/IHC Profile -Lynch/HNPCC Screen

Aliases Lists additional common names for a test, as an aid in searching

DNA Mismatch Repair-related HNPCC
Hereditary Nonpolyposis Colon Cancer (HNPCC)
Immunohistochemistry (IHC)
Lynch Syndrome
Microsatellite Instability (MSI)
Tumor Microsatellite Instability (MSI)
Hereditary Non-Polyposis