Eur Radiol (2005) 15: 1705–1712 DOI 10.1007/s00330-005-2642-z ONCOLOGY J. Monill J. Pernas E. Montserrat C. Pérez J. Clavero A. Martinez-Noguera R. Guerrero S. Torrubia Received: 16 June 2004 Revised: 9 December 2004 Accepted: 20 December 2004 Published online: 27 January 2005 # Springer-Verlag 2005 CT features of abdominal plasma cell neoplasms Abstract The aim of this study was to describe the CT features of abdominal plasma cell neoplasms. We reviewed CT imaging findings in 11 patients (seven men, four women; mean age 62 years) with plasma cell neoplasms and abdominal involvement. Helical CT of the entire abdomen and pelvis was performed following intravenous ad- ministration of contrast material. Im- ages were analyzed in consensus by two radiologists. Diagnoses were made from biopsy, surgery and/or clinical follow-up findings. Multiple myeloma was found in seven patients and extramedullary plasmacytoma in four patients. All patients with mul- tiple myeloma had multifocal disease with involvement of perirenal space (4/7), retroperitoneal and pelvic lymph nodes (3/7), peritoneum (3/7), liver (2/7), subcutaneous tissues (2/7) and kidney (1/7). In three of the four patients with extramedullary plasma- cytoma, a single site was involved, namely stomach, vagina and retro- peritoneum. In the fourth patient, a double site of abdominal involvement was observed with rectal and jejunal masses. Plasma cell neoplasm should be considered in the differential diag- nosis of single or multiple enhancing masses in the abdomen or pelvis. Abdominal plasma cell neoplasms were most frequently seen as well- defined enhancing masses (10/11). Keywords CT . Abdomen . Myeloma . Plasmocytoma . Neoplasm Introduction Plasma cell neoplasms represent a spectrum of disorders comprising multiple myeloma, solitary plasmacytoma of bone, extramedullary plasmacytoma (EMP) and plasma cell leukemia. Despite an apparent common origin in B-cells, there exist pathological and clinical differences between these neoplasms, and the association between these is not com- pletely understood [1–3]. Multiple myeloma is mostly confined to medullary sites and its predominant clinical manifestations are generally related to bone marrow infiltration and destruction of the bone. However, extramedullary involvement is seen in ap- proximately 70% of patients. The most frequently involved extraosseous lesions include hematopoietic tissues such as liver, spleen and lymph nodes [4, 5]. Extramedullary plasmacytoma differs from other forms of myeloma in that primary lesions arise outside the bone marrow, most commonly in the upper aerodigestive tract [6, 7]. Radiologic references to abdominal plasma cell tumors are very uncommon and generally limited to case reports. The purpose of this study was to describe the radiologic features of plasma cell neoplasms in the abdomen and pelvis. J. Monill (*) . J. Pernas . E. Montserrat . C. Pérez . J. Clavero . A. Martinez-Noguera . R. Guerrero . S. Torrubia Hospital de Sant Pau, Universitat Autonoma de Barcelona, Avda. Sant Antoni M. Claret 167, 08025 Barcelona, Spain e-mail: jmonills@menta.net