A 59-Year-Old Woman With HER2+ De Novo Metastatic Breast Cancer

April 16, 2020

A 59-Year-Old Woman With HER2+ De Novo Metastatic Breast Cancer


Case: A 59-Year-Old Woman WithHER2+ De Novo Metastatic Breast Cancer

Initial presentation

  • A 59-year-old, postmenopausal woman presented to her PCP for an annual physical exam, she was referred to undergo screening mammography; she reported back and hip pain along with occasional headaches
  • PMHx: diabetes, medically controlled
  • OB/GYNHx: nulliparous
  • FHx: no family history of cancer
  • PE: obese, palpable left breast mass with axillary adenopathy

Clinical workup

  • Labs: alkaline phosphatase 230 IU/L (normal range 20-140 IU/L); otherwise WNL
  • Breast imaging revealed a 2.1 cm irregular appearing mass in the left breast with suspicious axillary adenopathy
  • Ultrasound-guided core biopsy of the left breast mass and axillary node confirmed high-grade infiltrative ductal carcinoma; ER-, PR-,HER2,3+ by IHC
  • Brain MRI was negative
  • PET/CT and bone scan revealed multiple lesions in the spine and pelvis; and several pulmonary nodules; pulmonary nodule biopsy revealed invasive ductal carcinoma; ER-,HER2+
  • ECOG PS 1

Treatment and Follow-Up

  • She was started on paclitaxel + trastuzumab + pertuzumab and completed 6 months of chemotherapy at which point paclitaxel was discontinued due to worsening neuropathy; trastuzumab and pertuzumab were continued
  • Follow-up imaging at 3 months showed no FDG activity in the bones or lungs; bone pain resolved
    • Denosumab was started to reduce skeletal related events
  • Further follow-up imaging showed stable disease until 18 months when she developed worsening cough; imaging showed progressive bone disease and multiple new pulmonary nodules
    • Trastuzumab emtansine (T-DM1) was started
  • Follow-up imaging showed response to treatment which lasted for ~ 9 months
    • She developed headaches, and increasing bone pain
  • Brain MRI at that time showed 3 lesions, all < 2-cm; she was treated with SRS (stereotactic radio surgery)
    • Bone scan showed progressive bone metastases
  • Initiated neratinib 240 mg (6 tablets) PO QD + capecitabine
    • She was started on prophylactic loperamide