Abstract
Primary breast lymphoma (PBL) is an uncommon extranodal type of lymphoma, exhibiting more aggressive behavior and poorer prognosis. Patients with PBL have a higher incidence to relapse in central nervous system (CNS), which is always leading to a dismal outcome even treating with high intensity chemotherapy plus radiotherapy. Lymphoma involving the peripheral nervous system (PNS), either primarily or secondarily, is also rare. But no PBL with PNS relapse has been reported before. Herein, we reported a case of PBL who presented with subsequent relapse in two discrete sites of the PNS followed by the CNS.