Breast cancer
Management of HER2+ MBC

Josephine (69 years old)

Josephine, 69 years old, currently receives treatment with trastuzumab deruxtecan in second line for HR- HER2+ MBC.

Assessment summary

  • Postmenopausal
  • No relevant comorbidities
  • ECOG PS: 1
  • Medical history:
    • ~2 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
  • PET-CT at 14 months of trastuzumab deruxtecan treatment: new liver lesions
  • Brain MRI: partial response of brain metastases that were previously treated

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