title: Xanthoma of the sacrum.
abstract: Xanthoma is a lesion containing abundant foamy histiocytes most commonly occurring in superficial soft tissues such as skin, subcutis, or tendon sheaths. The involvement of deep skeletal structures, however, is rare and has only been infrequently reported in the English literature. Most xanthomas occur in patients with hyperlipidemic disorders. We report a case of a xanthoma in the sacrum and ilium of a patient with hyperlipidemia type IIa, who had chronic lower back pain for more than 20 years. On radiographs the lesion appeared multiloculated and osteolytic with a thin sclerotic border and containing multiple nodular calcifications within its matrix. Computed tomographic images revealed a presacral soft-tissue mass that also infiltrated the adjacent sacroiliac joint and iliac fossa. On histologic examination, abundant areas of xanthoma cells and cholesterol clefts, typical of xanthoma, were present. The patient received simple curettage of the lesion, and his symptoms were markedly relieved.
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, 325, Sec.2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, Republic of China. gsh5@seed.net.tw
authors.forename: Guo-Shu
authors.initials: GS
authors.lastname: Huang
authors.forename: Chih-Wang
authors.initials: CW
authors.lastname: Huang
authors.forename: Chian-Her
authors.initials: CH
authors.lastname: Lee
authors.forename: John A M
authors.initials: JA
authors.lastname: Taylor
authors.forename: Chih-Gueng
authors.initials: CG
authors.lastname: Lin
authors.forename: Cheng-Yu
authors.initials: CY
authors.lastname: Chen
mesh_terms: D003937:Diagnosis, Differential; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000175:diagnosis; D007085:Ilium / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000175:diagnosis; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging / Q000473:pathology; D012447:Sacrum / Q000000981:diagnostic imaging* / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D014973:Xanthomatosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology