How would you manage tucatinib-associated grade 2 indirect hyperbilirubinemia in a patient with metastatic HER2-positive breast cancer involving the CNS is receiving trastuzumab + capecitabine + tucatinib?  

Patient is young. Bilirubin normalizes when tucatinib is held, but again increases to grade 2 when it is restarted. Evaluation for hemolysis was negative. Direct bilirubin normal and no obvious liver toxicity.

How might your management change if a patient already progressed on THP, T-DM1 and T-Dxd?



Answer from: Medical Oncologist at Academic Institution