Ordering Recommendation

Detect germline PMS2 variants. Use in MMR-deficient carcinoma with suggestive IHC results (isolated loss of PMS2 protein).

Mnemonic
PMS2 FGA
Methodology

Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification

Performed

Varies

Reported

28-35 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Lavender (K2EDTA), Pink (K2EDTA), or Yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 1 week; Refrigerated: 1 month; Frozen: 6 months

Reference Interval
Interpretive Data

Background information for HNPCC/Lynch Syndrome (PMS2) Sequencing and Deletion/Duplication
Characteristics of Lynch Syndrome:
Increased risk of colorectal and extra-colonic cancers including endometrial, renal pelvis, ureter, ovary, stomach, small intestine and hepatobiliary tract.
Incidence:
1-2 percent of colorectal cancer is due to mismatch repair gene mutations.
Inheritance:
Autosomal dominant.
Penetrance:
Unknown for PMS2 mutations.
Cause:
Pathogenic germline MLH1, MSH2, MSH6, and PMS2 gene mutations.
Gene tested:
PMS2
Clinical Sensitivity: Less than 5 percent of Lynch syndrome cases are due to PMS2 mutations.
Methodology:
Bidirectional sequencing of PMS2 coding regions and intron-exon boundaries; multiplex ligation-dependent probe amplification (MLPA) to detect large PMS2 exonic deletions.
Analytical Sensitivity & Specificity:
99 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. Mutations in genes other than PMS2 are not evaluated. This assay is not designed to detect somatic variants associated with malignancy. Interpretation of this test result may be impacted if the patient has had an allogeneic stem cell transplantation.

Compliance Category

Laboratory Developed Test (LDT)

Note

Suspected deletions or duplications in exons 12-15 require additional sequencing to exclude pseudogene copy number variants.  Additional charges apply.

Hotline History
N/A
CPT Codes

81317; 81319; If pseudogene analysis is performed add: 81479

Components
Component Test Code* Component Chart Name LOINC
0051738 Lynch Syndrome (PMS2) Interpretation
2001372 PMS2 FGA Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • HNPCC
  • PMS2 gene testing
  • PMS2 genotyping
  • PMS2 germline assay
HNPCC/Lynch Syndrome (PMS2) Sequencing and Deletion/Duplication