Mutational testing determines whether you have a mutation present in your tumor, and what genotype it is. Examples include Exon 11 or 9 (for KIT positive tumors), Platelet Driven Growth Factor Receptor Alpha (PDGFRA), or “Wild Type” (no mutation). As different mutations respond to different drugs, and different doses of those drugs, knowing if a specific mutation is present can help your doctor determine the best type of treatment for your individual situation.
Plasma/Blood Level Testing (BLT) is a pharmokinetic method of determining how much imatinib (Gleevec) is present in a patient’s blood at a specific time. Typically, the minimum concentration (known as a trough level or Cmin) is measured right before taking the next dose of Gleevec (ideally 22-24 hours after taking the last dose). By measuring this level doctors can see if a patient is taking their Gleevec as prescribed.