Four cases of Trousseau syndrome associated with breast cancer that exhibited central nervous system manifestations.

Cancer-associated thrombosis is known as Trousseau syndrome (TS). Here, we report 4 cases of TS associated with advanced breast cancer that caused central nervous system (CNS) vascular events. All 4 patients experienced sudden onset of CNS symptoms. Imaging revealed multiple brain infarctions or intracranial hemorrhage and all 4 patients had leptomeningeal or brain metastasis. Laboratory findings showed hypercoagulability at diagnosis of TS. Of the 4 patients, 2 patients were treated with unfractionated heparin, while 2 patients could not undergo anticoagulant therapy. In all patients, once the TS occurred, the CNS symptoms progressed rapidly and the prognosis was very poor, 3 patients dying within about a month of diagnosis of TS. Therefore, the predictive factors of TS are important and standards and guidelines for administration of anticoagulants are needed. © The Japan Society of Clinical Oncology 2020.