MSH2, IHC without Interpretation

Test Code

16971

CPT Codes
88342

Preferred Specimen

Formalin fixed paraffin embedded tissue in an IHC specimen transport kit

Other Acceptable Specimens

Unstained charged (+) slides (x5)

Transport Temperature

Room temperature

Specimen Stability

Room temperature: Indefinite
Refrigerated: Indefinite
Frozen: Unacceptable

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Samples other than a paraffin block

Methodology
Immunohistochemistry (IHC)

Setup Schedule

A.M.

Clinical Significance

Human mismatch repair protein 2 (MSH2) is involved in the initial recognition of mismatched nucleotides during the post replication mismatch repair process. Therefore, the loss of MSH2 function leads to the accumulation of replication errors, which in turn may be responsible for the multiple mutation required for multistage carcinogenes. Mutations in mismatch repair genes have been linked to hereditary nonpolyposis colon cancer and to sporadic cancers which exhibit microsatellite instability. MSH2 is reported to be expressed in the nuclei of cells from a variety of tissues including thyroid, heart, smooth muscle and the germinal centers of lymphoid follicles. In ileum and colon, MSH2 expression has been reported in the crypts, the cells of which are undergoing repid renewal. They are responsible for the continuous production of differentiated cells which migrate over 2 to 4 days before being sloughed into the lumen.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.