Early HER2+ Breast Cancer

Case: A 52-Year-Old Woman withHER2+ Breast Cancer

H & P

• A 52-year-old, postmenopausal woman presented with a mass in her left breast at her annual gynecologic exam; was referred to oncology
• 2 children, menopause at age 49
• No history of cardiovascular disease, no family history of breast cancer
• PE: reveals a slightly overweight woman (BMI = 26 kg/m²), with palpable masses in left breast and left axillary nodes

Imaging

• Mammogram reveals 2.5-cm tumor in left breast
• CT: confirms tumor in left breast and left axillary node involvement (2.6-mm metastasis in 1 node)

Biopsy and labs:

• Histology: invasive ductal adenocarcinoma
• Histologic grade: G2
• ER (-)/ PR (-)
• HER2IHC, 3+
• BRCA1/2status: unknown

Treatment

• She received neoadjuvant TCH-P (docetaxel + carboplatin + trastuzumab + pertuzumab) and achieved pathologic complete response
  • Developed grade 3 diarrhea during second cycle of chemotherapy, which required a one-level dose reduction of paclitaxel
  • Diarrhea resolved to grade 1/2
• Underwent breast-conserving surgery and removal of left axillary lymph nodes; no residual disease
• Currently completing adjuvant therapy; trastuzumab + pertuzumab (total 18 cycles)