Allina Health Laboratory a part of Abbott Northwestern Hospital



A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers

Test Name:PMS2 by IHC
Test Number:12376 - Technical only; 12379 - Technical & Interpretation
Collect:Formalin-fixed, paraffin embedded (FFPE) tissue block
Container:FFPE tissue block
Processing:Submit processed tissue block or tissue section mounted on a charged, unstained slide
Transport/Stability:Ambient (preferred)
Alternate Names:Microsatellite instability marker
Performing Lab:AHL - Immunohistochemistry
Days Set Up:Mo - Fr
Expected TAT:1 - 2 days
Ref. Ranges:If requested, an interpretive report will be provided
All IHC stains will include a positive control tissue
Processing Details:

  • Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is an autosomal dominant hereditary cancer syndrome associated with germline mutations in the mismatch repair genes: MLH1, MSH2, MSH6, and PMS2
  • Patients with HNPCC have an increased risk of developing colorectal and endometrial cancer
  • Mutations of the PMS2 gene confer the lowest risk for any of the tumors within the HNPCC spectrum
Staining pattern:
  • Nuclear staining of internal control lymphocytes, and PMS2 intact tumor cells
  • Absence of staining for PMS2 in tumor nuclei indicates loss of protein expression for this marker
  • Used in a panel to identify patients at high risk for having hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome
  • IHC analysis is helpful for identifying the gene(s) responsible for the defective DNA mismatch repair within the tumor; the majority of MSI-H tumors show a loss of expression of at least 1 of the 4 mismatch repair genes
  • MSI-H phenotype or loss of protein expression by IHC within a tumor does not distinguish between somatic and germline mutations. Genetic testing of the gene indicated by IHC analysis can help to distinguish between these 2 possibilities.
  1. Burgart LJ: Testing for defective DNA mismatch repair in colorectal carcinoma. A practical guide. Arch Pathol Lab Med 2005;129:1385-1389.

Method:Immunohistochemical staining
Microscopic examination
CPT Codes:88342 - 1st stain
88341 - each additional stain
Date Created:10/30/2017
Revised Date:10/19/2018