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GTR Home > Tests > Mismatch Repair Proteins by Immunohistochemistry


Test order codeHelp: IHC for MLH1, MSH2, MSH6, PMS2

Test name


Mismatch Repair Proteins by Immunohistochemistry (MMR IHC)

Purpose of the test


This is a clinical test intended for Help: Diagnosis, Screening



Click Indication tab for more information.

How to order


use the IHC requisition form and select the proteins you want stained by IHC CPT codes are 88342 x1, and 88341 x3
Order URL Help: http://www.gopathlabs.com/contact_us/

Specimen source

Fresh tissue
Frozen tissue
Paraffin block


Biochemical Genetics
Antibody detection
  • None/not applicable

Summary of what is tested

Click Methodology tab for more information.

Clinical utility


Not provided

Clinical validity


Not provided

Test services

  • Immunohistochemistry, Order code: 88342x1, 88341x3

Suggested reading

Practice guidelines

  • EHTG/ESCP, 2021
    European guidelines from the EHTG and ESCP for Lynch syndrome: an updated third edition of the Mallorca guidelines based on gene and gender
  • ACMG, 2016
    Recommendations for reporting of secondary findings in clinical exome and genome sequencing, 2016 update (ACMG SF v2.0): a policy statement of the American College of Medical Genetics and Genomics.
  • ASCO, 2015
    American Society of Clinical Oncology Policy Statement Update: Genetic and Genomic Testing for Cancer Susceptibility
  • Mork et al., 2015
    Lynch Syndrome: A Primer for Urologists and Panel Recommendations.
  • ACG, 2015
    ACG clinical guideline: Genetic testing and management of hereditary gastrointestinal cancer syndromes.
  • ASCO/ESMO, 2015
    Hereditary colorectal cancer syndromes: American Society of Clinical Oncology Clinical Practice Guideline endorsement of the familial risk-colorectal cancer: European Society for Medical Oncology Clinical Practice Guidelines.
  • ACMG, 2015
    ACMG policy statement: updated recommendations regarding analysis and reporting of secondary findings in clinical genome-scale sequencing.
  • MSTF, 2014
    Guidelines on genetic evaluation and management of Lynch syndrome: a consensus statement by the US Multi-society Task Force on colorectal cancer.
  • ASCO, 2014
    American Society of Clinical Oncology Expert Statement: collection and use of a cancer family history for oncology providers.
  • SGO, 2014
    Society of Gynecologic Oncology (SGO) Clinical Practice Statement: Screening for Lynch Syndrome in Endometrial Cancer
  • ACMG, 2014
    ACMG technical standards and guidelines for genetic testing for inherited colorectal cancer (Lynch syndrome, familial adenomatous polyposis, and MYH-associated polyposis).
  • ACMG, 2013
    ACMG recommendations for reporting of incidental findings in clinical exome and genome sequencing.
  • Dutch SCG, 2013
    Informing family members of individuals with Lynch syndrome: a guideline for clinical geneticists.
  • Mallorca group, 2013
    Revised guidelines for the clinical management of Lynch syndrome (HNPCC): recommendations by a group of European experts. (See EHTG/ESCP, 2021 Update)
  • CAPS, 2013
    International Cancer of the Pancreas Screening (CAPS) Consortium summit on the management of patients with increased risk for familial pancreatic cancer (See 2020 Update)
  • EGAPP, 2009
    Recommendations from the EGAPP Working Group: genetic testing strategies in newly diagnosed individuals with colorectal cancer aimed at reducing morbidity and mortality from Lynch syndrome in relatives
  • NSGC, 2004
    Genetic cancer risk assessment and counseling: recommendations of the National Society of Genetic Counselors. (Retired following 2012 Update)
  • ASCRS, 2001
    Practice parameters for the identification and testing of patients at risk for dominantly inherited colorectal cancer--supporting documentation.

Consumer resources

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