{"Thioguanine can be affected by a patient's TPMT and NUDT15 phenotype. This patient is predicted to be a NUDT15 normal metabolizer. Based on that specific result, the patient may receive a standard starting dose of thioguanine. However, TPMT status could not be determined based on genotyping performed. Consider evaluating TPMT erythrocyte activity to assess TPMT phenotype. Erythrocyte TPMT activity test results can be falsely low at diagnosis of leukemia and is unreliable in the case of recent red blood cell transfusions. If thioguanine is required and TPMT status is unknown, monitor closely for toxicity."}