Breast cancer
Management of HER2+ MBC

Martha (72 years old)

Martha, 72 years old, received trastuzumab + tucatinib + capecitabine for a duration of 26 months as third-line treatment for HER2+ MBC. She has a follow-up visit today.

Assessment summary

  • Postmenopausal
  • Medical history:
    • ~4.5 years ago: diagnosis de novo HR- HER2+ MBC
    • Tumour biology (liver lesion): invasive ductal carcinoma, ER 0%, PgR 0%, HER2 IHC 3+
    • First-line treatment for bone, liver and lung metastases:
      • Paclitaxel + trastuzumab-pertuzumab for 10 months
    • Second-line treatment for liver and brain progression:  
      • SRS for the 3 brain metastases
      • Trastuzumab deruxtecan for 14 months without toxicity
    • Third-line treatment for liver progression:
      • Tucatinib + trastuzumab + capecitabine for 26 months with partial response as best response
      • Minor hand-foot syndrome (grade 1) thanks to diclofenac use

She comes to the clinic for new staging:

  • ECOG PS: 1
  • Biology: AST 2.5x ULN, ALT 2.5x ULN, bilirubin <1.5x ULN
  • PET-CT: miliary liver progression
  • New liver metastasis biopsy: invasive ductal carcinoma, ER 30%, PgR 0%, HER2 IHC 3+

Which of the following treatment options would you choose for this patient?