IMAGES IN CYTOLOGY

Section Editor: Shahla Masood, M.D.

Fine-Needle Aspiration of aPresacral MyelolipomaYun Gong, M.D.,1* and Xiaoping Sun M.D., Ph.D.2

Myelolipomas are benign tumors composed of normal

hematopoietic components and mature adipose tissue and

occur primarily in the adrenal glands of older women.

Extra-adrenal myelolipomas are much less frequent; about

50% of these occur in the presacral region and are either

asymptomatic or symptomatic. Fine-needle aspiration

(FNA) cytology of presacral myelolipoma has rarely been

reported.

An 83-yr-old woman presented with a long-standing

history of low back pain. CT and magnetic resonance

imaging revealed a 3.5-cm, well-circumscribed, heteroge-

neous, presacral mass at the S2 level, containing foci with

a fat density; the mass was interpreted to be a lipomatous

tumor or liposarcoma. There was no bone involvement.

CT-guided FNA revealed trilineage hematopoietic ele-

ments admixed with scattered lymphoid cells against a

background of mature fat cells (Fig. C-1A). A diagnosis

of myelolipoma was made on the basis of these cytologic

findings in conjunction with the radiologic findings and

was later confirmed in a cell-block preparation (Fig. C-1B).

Notably, however, the low-power view of these

cells gave the impression of a ‘‘mixed/polymorphous’’

lymphoid background. The numerous eosinophils,

occasional binucleated megakaryocytes with an open

chromatin pattern, and distinct nucleoli (reminiscent of

Reed–Sternberg cells; Fig. C-1A, inset) could be mistaken

for Hodgkin’s lymphoma. Diff-Quik (DQ) staining of an

air-dried smear can facilitate in demonstrating the hema-

topoietic nature of the lesion and identifying the fat drop-

lets. Differential diagnosis should also include extrame-

dullary hematopoiesis of a retroperitoneal lymph node in

response to hematologic abnormalities and incidentally

sampled bone marrow components. A lipomatous lesion

or liposarcoma is characterized cytologically by lipocytes

with varying atypia in a delicate vascular network without

hematopoietic elements.

Preoperative recognition of this unusual tumor on the

basis of FNA findings is essential for ensuring the appro-

priate care of these patients. It is important to consider

presacral myelolipoma in the differential diagnosis of

a retroperitoneal/presacral mass. Extra-adrenal myeloli-

poma can be accurately diagnosed by carefully evaluat-

ing individual cells and correlating it with the radiologic

findings.

1Department of Pathology, The University of Texas M. D. AndersonCancer Center, Houston, Texas

2Department of Laboratory Medicine, The University of Texas M. D.Anderson Cancer Center, Houston, Texas

*Correspondence to: Yun Gong, M.D., Assistant Professor, Depart-ment of Pathology, Unit 53, The University of Texas M.D. AndersonCancer Center, 1515 Holcombe Blvd., Houston, TX 77030.E-mail: yungong@mdanderson.org

Received 3 September 2004; Accepted 7 January 2005DOI 10.1002/dc.20264Published online in Wiley InterScience (www.interscience.wiley.com).

' 2005 WILEY-LISS, INC. Diagnostic Cytopathology, Vol 34, No 1 29

Fig. C-1. (A) Smears showing trilineage hematopoietic elements, lymphoid cells, and mature fat droplets. Inset shows a binucleatedmegakaryocyte with distinct nucleoli, reminiscent of a Reed–Sternberg cell (Papanicolaou stain, �200). (B) Cell block of FNA materialshowing trilineage hematopoietic elements admixed with mature adipose tissue (H&E stain, �200).

GONG AND SUN

30 Diagnostic Cytopathology, Vol 34, No 1