Current Problems in Cancer: Case Reports (Dec 2020)
Gastrointestinal metastatic breast cancer unmasked by anticoagulation
Abstract
Background: Cancer is a leading cause of provoked venous thromboembolism (VTE) and requires use of anticoagulation. As the incidence of lobular breast carcinoma increases, more breast cancer patients experience gastrointestinal metastatic disease which often manifests with gastrointestinal bleeding. Herein we discuss the challenges associated with the diagnosis and management of breast cancer metastatic to the GI tract revealed by need for anticoagulation due to concurrent cancer-associated VTE. Case: A 72 year old woman with a past medical history of ER+ PR+ HER2- Stage IIIa left lobular breast carcinoma previously treated with neoadjuvant chemotherapy, bilateral mastectomies and radiation followed by adjuvant hormonal therapy with letrozole. After 2 years of adjuvant hormonal therapy, she was diagnosed with unprovoked VTE. She was started on rivaroxaban for indefinite anticoagulation. After 5 months she presented with complaints of melena and weakness and a hemoglobin of 7.1 g/dL and platelets of 110 x 109/L. Esophagoduodenoscopy was performed which showed acute gastritis with random gastric biopsies noted to be positive for metastatic lobular breast carcinoma. Due to GI bleeding, rivaroxaban was held, however the patient developed an acute proximal right femoral vein VTE. A second trial of anticoagulation with heparin did not reveal continued bleeding, so she was discharged on apixaban. Unfortunately, despite starting chemotherapy with ibrance and faslodex she developed worsening melena resulting in the need to the place an IVC filter and cessation of anticoagulation. Discussion: As lobular breast cancer can spread along serosal surfaces, new onset of GI bleeding in patients with history of lobular breast cancer should increase suspicion for GI metastatic disease. Use of anticoagulation may unmask bleeding in such patients. The increased risk of GI bleeding in cancer patients must be considered when selecting anticoagulation for the management of cancer-associated VTE. Management of cancer associated thrombosis is complex and hemostasis strategies for of mucosal bleeding from metastatic lobular breast cancer may require tailored approaches that compensate for the malignant cause. Furthermore, a thorough assessment of platelet counts and other coagulation factors should be considered as a minority of patients with metastatic disease can present with consumptive coagulopathy.
