MSI (PCR) X 2




Test Mnemonic

MSICCT

CPT Codes

  • 81301 - QTY (1)

Aliases

  • Microsatellite Instability (MSI) x 2

Performing Laboratory

Cleveland Clinic Laboratories


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
OtherOtherOther  Representative tumor: formalin-fixed, paraffin-embedded block, OR 10 unstained slides
OtherOtherOther  Representative patient normal: formalin-fixed, paraffin-embedded block, 5 unstained slides, preferably from separate block

Alternate Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
4 mLWhole bloodEDTA (Lavender)AmbientAmbientRepresentative patient normal: Whole blood if no FFPE tissue is available (e.g. small biopsies)

Stability

Environmental Condition Description
AmbientWhole Blood- 48 hours; Paraffin-Embedded tissue- indefinitly
RefrigeratedWhole blood- 7 days
Frozenunacceptable

Days Performed

2 days per week

Turnaround Time

7 days

Methodology

Name Description
Capillary Electrophoresis (CE) 
Polymerase Chain Reaction (PCR) 

Special Info

Please order this procedure when there are two specimens. Submit tissue specimen with anatomic pathology request form, and indicate MSI on the form. Histopathologic review will be performed. DNA mismatch repair immunohistochemistry may be added on to or substituted for MSI testing. BRAF mutation testing will be performed on all MSI-high, MLH1 loss cancers.

Clinical Info

Screening test for Hereditary Non-Polyposis Colorectal Cancer (HNPCC)