ER/PR/HER2-positive breast cancer: gallbladder, liver, lung, pleural, and bone metastases after incomplete adjuvant therapy

What happened, in summary

This 43-year-old premenopausal woman first presented in August 2020 with 1 year of skin dimpling over the right superomedial breast and 2 months of a palpable mass. Mammography showed a 3.6 × 2.4 × 3.5 cm right breast mass, and biopsy confirmed infiltrating ductal carcinoma that was ER-positive, PR-positive, and HER2-positive. Initial staging was cT2N0M0, Stage IB. Neoadjuvant docetaxel, carboplatin, trastuzumab, and pertuzumab was planned for 6 cycles, but treatment was delayed by insurance problems. Lumpectomy occurred 10 months after tissue diagnosis. Pathology showed 1.3 cm residual invasive ductal carcinoma, clear margins, no lymphovascular invasion, and 5 negative sentinel nodes. She completed whole-breast radiation 3 months after lumpectomy. Trastuzumab, tamoxifen, and goserelin were planned, but 5 months after lumpectomy all interventions were stopped because of suicidal ideation, and she did not return for surveillance. More than 3 years later, she developed nausea, vomiting, low appetite, fatigue, productive cough, and then right upper-quadrant pain. She underwent laparoscopic cholecystectomy for presumed acute cholecystitis. Pathology unexpectedly showed metastatic breast carcinoma in the gallbladder, positive for GATA3, ER, PR, HER2, CK7, CK19, and CAM5.2, with Ki-67 greater than 40%. Eighteen days later, CT showed suspected recurrent breast disease plus ascites, liver metastases, bilateral lung metastases, and bone metastases involving the right clavicle, left ribs, and sternum. Pleural fluid confirmed malignant mammary carcinoma. Goserelin was started, followed by trastuzumab and pertuzumab, but her condition rapidly worsened. She transitioned to comfort care and died on hospital day 10, 3 years and 10 months after lumpectomy.