P1998 - Think Outside the Breast: A Case Series of Gastrointestinal Manifestations of Breast Cancer

Joanne Lin, DO¹, Annie Shergill, MD², Qinglong Hu, MD³, Abhishek Gulati, MD^3
1UCSF Fresno, Fresno, CA; ²Larkin Community Hospital, Miami, FL; ³Clovis Community Medical Center, Clovis, CA

Introduction: Breast cancer is the second most common cancer and the second leading cause of cancer deaths in women. Typical metastasis sites include bone, liver, lungs, and brain. We present two cases that highlight rare gastric and pancreatic metastases of breast cancer.

Case Description/Methods: A 67-year-old woman with a history of breast cancer metastasized to the lungs was referred to the gastroenterology clinic for evaluation of abdominal pain. She was diagnosed with breast cancer 6 years ago, had a bilateral mastectomy, and has been receiving treatment with oncology. Esophagogastroduodenoscopy (EGD) revealed two non-bleeding cratered gastric body ulcers. Pathology of the ulcers revealed poorly differentiated carcinoma with breast primary (Figure A).

A 58-year-old woman with a history of breast cancer presented to the emergency department with worsening pruritis and jaundice. She was noted to have elevated bilirubin during a clinic visit and was informed to come for further evaluation. She was diagnosed with breast cancer 4 years ago, had a right-sided mastectomy, and was currently not on chemotherapy. CT abdomen did not show any evidence of a mass. A pancreatic mass in the uncinate process was noted on endoscopic ultrasound (EUS), and fine needle aspiration (FNA) was performed. FNA resulted as poorly differentiated adenocarcinoma consistent with breast primary and she was re-started on chemotherapy (Figure B).

Discussion: Breast cancer accounts for less than 5% of metastatic pancreatic masses and about 0.2% to 18% of stomach metastases. As breast cancer treatment options expand and survival improves, metastasis to unusual locations, such as those described in our case reports, are bound to increase. Our cases emphasize the importance of identifying these unusual locations of metastasis and differentiating it from primary gastrointestinal and pancreatic cancer so patients may receive proper individualized treatment based on histology and site.



Disclosures:


Joanne Lin, DO¹, Annie Shergill, MD², Qinglong Hu, MD³, Abhishek Gulati, MD³. P1998 - Think Outside the Breast: A Case Series of Gastrointestinal Manifestations of Breast Cancer, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.