In May, 2017, the FDA granted accelerated approval for the use of Keytruda for treatment of patients with unresectable or metastatic solid tumors having either microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) biomarkers. Keytruda, a human PD-1 blocking antibody, is indicated for the treatment of metastatic melanoma, non-small cell lung cancer, recurrent or metastatic head and neck squamous cancer, advanced/metastatic urothelial cancer and classical Hodgkin’s lymphoma.
This contractor will allow one of the following:
- dMMR by immunohistochemistry (IHC), or
- MSI by PCR, or
- Multi-gene NGS panel inclusive of MSI microsatellite loci, and MLH1, MSH2, MSH6 and PMS2 genes
Testing by one of the above methodologies is reasonable and necessary if testing for dMMR or MSI has not previously been performed on the patient’s tumor sample. A multi-gene NGS panel inclusive of MSI microsatellite loci and MLH1, MSH2, MSH6 and PMS2 gene is reasonable and necessary. A multi-gene NGS panel and separate MSI by PCR will be denied as not reasonable and necessary. If testing is performed by NGS, the test must be a properly designed and appropriately validated assay demonstrating 95% concordance to the reference method (MSI by PCR).
To report a dMMR service, please submit the following claim information:
- CPT code 88342 – One (1) unit of service
- CPT code 88341 – Three (3) units of service
To report a MSI service, please submit the following claim information:
To report by NGS, please submit the following claim information: