Dedifferentiated liposarcoma of retroperitoneum: spectrum of imaging findings in 15 patients
Received 2 November 2009; accepted 20 December 2009. published online 12 March 2010.
Abstract
Background
Dedifferentiated liposarcoma is a high-grade nonlipogenic sarcoma that arises in the background of a preexisting well-differentiated liposarcoma. The purpose of this work is to evaluate the spectrum of radiologic appearance of retroperitoneal dedifferentiated liposarcoma with clinicopathologic features.
Methods
Radiologic images and clinical histories of 15 patients with histologically verified retroperitoneal dedifferentiated liposarcoma were retrospectively studied. Patients included 11 men and 4 women, with mean age of 55.8 years (range, 36–74 years), and they underwent computed tomography (CT) (n=15) and magnetic resonance imaging (MRI) (n=5).
Results
The mean size of the tumor was 22.6 cm with a range of 9.5–38 cm. Both CT and MRI showed well-circumscribed, large round, or lobulated retroperitoneal mass. The appearance of the tumor was classified as follows: Category I, nonfatty component within predominant fatty mass (n=5); Category II, focal fatty component within large nonfatty mass (n=6); Category III, well-defined fatty mass and well-defined nonfatty mass (n=1); Category IV, two masses with predominantly nonfatty component (n=3).
Conclusion
Retroperitoneal dedifferentiated liposarcomas present various spectra of imaging findings. While Categories I and III may suggest dedifferentiated liposarcoma, Categories II and IV may appear as other types of liposarcoma or other malignant retroperitoneal tumor.
aDepartment of Radiology, Korea University College of Medicine, Seoul, South Korea
bDepartment of Pathology, Korea University College of Medicine, Seoul, South Korea
cYonsei University College of Medicine, South Korea
dSeoul National University College of Medicine, South Korea
eCatholic University College of Medicine, Seoul, South Korea
Corresponding author. Department of Radiology, Guro Hospital, Korea University College of Medicine, 97 Gurodong-Gil, Guro-Ku, Seoul 152-703, South Korea. Tel.: +82 2 2626 1338; fax: +82 2 863 9282.
ABSTRACT