髓外浆细胞瘤(extramedullary plasmacytoma,EMP)是指原发于骨髓造血组织外的浆细胞肿瘤,是浆细胞瘤中较为罕见的一种,占所有浆细胞肿瘤的1.9%~2.8%。尽管EMP可发生于任何髓外组织器官[1],但80%发生于头颈部,尤其是上呼吸道,如鼻腔、鼻窦、咽喉部、涎腺。诊断上需要与伴有明显浆细胞分化的大B细胞淋巴瘤或者边缘带B细胞淋巴瘤鉴别,治疗上以放疗为主。而原发于腹膜后的髓外浆细胞瘤较罕见,因发病部位的特殊给诊断 Extramedullary plasmacytoma (extramedullary plasmacytoma, EMP) is a plasma cell tumor originating from the hematopoietic tissue of the bone marrow. It is a rare plasma cell tumor, accounting for 1.9% -2.8% of all plasma cell tumors. Although EMP can occur in any extramedullary tissue and organ [1], 80% occur in the head and neck, especially in the upper respiratory tract, such as the nasal cavity, sinuses, throat, and salivary glands. Diagnostic needs and significant plasma cell differentiation accompanied by large B cell lymphoma or marginal zone B cell lymphoma identification, the treatment of radiotherapy based. The primary retroperitoneal extracerebral plasmacytoma is rare, due to the special part of the diagnosis to the disease