Breast cancer
Progression after CDK4/6i + ET for HR+ HER2- MBC. What now?Ernestine (58 years old)
Ernestine, 58 years old, was diagnosed with primary metastatic breast cancer.
Assessment summary:
- Postmenopausal
- No relevant comorbidities or family history
- Diagnosis de novo HR+ HER2- metastatic breast cancer with multiple spine and liver metastases
- Tumour biology (liver lesion): invasive carcinoma of NST, ER 90%, PgR 40%, HER2 IHC 1+, Ki67 30%
- First-line treatment: CDK4/6i + letrozole
- CT scan after 3 months: partial response
- CT scan after 6 months (3 additional months): stable disease
- CT scan after 12 months (6 additional months): stable disease in spine, new multiple lesions in liver (accompanied with severe organ dysfunction: GOT 10x ULN, GPT 9x ULN, bilirubin 2x ULN), absence of biliary tract obstruction. She presents with loss of appetite, weight loss, and increased fatigue
- Second-line treatment: carboplatin and 5-fluorouracil due to severe organ dysfunction
- CT scan at end of chemotherapy: partial response and recovery of organ dysfunction
Today, CT scan 6 months after end of chemotherapy: new liver lesions.
- Liver function tests (AST and ALT) 1.5x ULN, bilirubin normal
- Biopsy (liver lesion): ER 70%, PgR 40%, HER2 IHC 1+, Ki67 20%
- Somatic PIK3CA mutation status: wild type
- Somatic ESR1 mutation status: wild type
- Germline BRCA mutation status: wild type