Advancing Precision Medicine Through Comprehensive Genomic Profiling (CGP) - Episode 9

Molecular Testing in Oncology: Current Practice Patterns

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Oncologists describe how they use molecular profiling in their practices to assess patients with solid tumor cancers.

Bruce Feinberg, DO: Kenna, is there a single CGP [comprehensive genomic profiling] with 500 genes that’s routine at [The University of Texas] MD Anderson [Cancer Center]? Does every patient who comes in the door with a newly diagnosed metastatic cancer get it? Tell me how it’s used. How is profiling done? I was working on a project with MedStar Georgetown [University Hospital], and for the last 5 years, every new metastatic patient gets a profile. They’ve got a bank, and hopefully we’re able to extract information, probably as a Watson project that failed. Kenna, how was it used at MD Anderson?

Kenna R. Mills Shaw, PhD: We don’t comprehensively profile every patient who walks in. Regardless of diagnosis, we have a molecular technology evaluation committee, and that committee maps. Essentially a clinician says, “This is a specific biomarker in this specific tumor type. These are the clinical data that support the testing of this biomarker. This is how I’m going to use it clinically.” TP53 is an approved biomarker for many tumor types because it helps our clinician say, “I’m going to treat this patient more aggressively. I’m going to watch and wait X patient vs I’m going to push this patient to transplant in the context of leukemia.” As long as a clinician has a body of clinical information that suggests that testing the biomarker in that disease context is going to help them change their care pathway, that gets approved by this committee. All the documentation—the literature, the evidence—for our payers…allows us to ensure that if a clinician asks for a test for a patient, it’s highly likely to get reimbursed on the other end because there’s a sufficient amount of evidence. We don’t generally use clinical sequencing—CLIA [Clinical Laboratory Improvement Amendments]–approved sequencing—for research. We use it only when it’s going to change the care for a patient.

Melanoma has an approved match. Melanoma has approved matches between specific molecular biomarkers and treatments, so they get tested.

Bruce Feinberg, DO: But that panel is not the 12. That panel plus the TMB [tumor mutational burden]. That panel is 500?

Kenna R. Mills Shaw, PhD: No clinician asks for a specific panel. The tests are ordered on a diagnosis and a biomarker-specific basis. I can order 5 biomarkers in my specific disease site. The assay that’s run is chosen by the pathologists in our institution. It’s a several-hundred-gene panel that provides our clinicians with copy number information, mutation information, as well as MSI [microsatellite instability] and tumor mutation burden. It’s a copy of the panel.

Bruce Feinberg, DO: That panel is different if you come in with a diagnosis of melanoma—from sarcoma, from lung, from breast. Or it’s the same panel?

Kenna R. Mills Shaw, PhD: The test is the same; the order is different. What I order for as a clinician and what we bill to insurance is going to be different, but the assay that’s run is identical.

Transcript edited for clarity.