Breast cancer (39)August 2019: breast biopsy for suspicious uptake on PET/CT for CRC: dx with ER+/PR+/HER2− IDC with axillary LN involvementNovember 2019: started tamoxifen after neoadjuvant FOLFOX and then switched to anastrazole after TAH/BSOFebruary 2021: progression of breast cancer, anastrazole stopped, surgery deferred while receiving FOLFIRI for CRCOctober 2021: lumpectomy with residual disease and matted nodes, deferred XRT and started exemestane. The gene discussed is ERBB2; the disease is breast cancer.