Diagnostic challenge of lipomatous uterine tumors in three patients

Abstract

Lipomatous uterine tumors are uncommon benign neoplasms, with incidence ranging from 0.03% to 0.2%. They can generally be subdivided into two types: pure or mixed lipomas. A third group of malignant neoplasm has been proposed, which is liposarcoma; however, this is very rare. In this article, we report three patients having lipomatous uterine tumors, including one uterine lipoma and two uterine lipoleiomyomas. All our patients are postmenopausal women, which is the typical presenting age group. They did not have any symptoms and the tumors were only found incidentally on imaging. However, in some patients, symptoms may uncommonly occur. If symptoms occur, these are similar to those of leiomyoma. We illustrate the imaging features of the tumors in our patients with ultrasound, computed tomography (CT) scan and magnetic resonance imaging (MRI). The tumor typically appears as a well-defined homogenously hyperechoic lesion on ultrasound. It shows fat density on CT scan and signal intensity of fat on MRI. MRI is the modality of choice because of its multiplanar capability and its ability to demonstrate fat component of the lesion, as illustrated in our cases. We also discuss the importance of differentiating lipomatous uterine tumors from other lesions, especially ovarian teratoma which requires surgical intervention. Despite the rarity and the common asymptomatic nature of the tumors, we believe that this series of three cases demonstrates a review of a rare tumor which provides important knowledge for patient management.

Keywords: Leiomyoma; Lipomatous; Magnetic resonance imaging; Uterine neoplasms; Uterus.

Figure 1

Computed tomography, ultrasound and magnetic resonance images of lipomatous uterine tumor in a 79-year-old woman. A and B: Computed tomography axial images of the pelvis without contrast (A) and with intravenous contrast (B) show a non-enhancing lesion in left side of the uterine fundus (long arrows); C: The density is similar to that of subcutaneous fat. Ultrasound of pelvis in transverse view shows a hyperechoic lesion (2.46 cm × 2.11 cm) in the uterine fundus; D: T1-weighted axial MRI image shows a homogeneous hyperintense lesion in left side of uterine fundus; E: The lesion shows complete suppression of signal intensity in T1-weighted fat-suppressed sequence, suggestive of fat component; F: No contrast enhancement is seen after intravenous gadolinium is administered. Compression of the uterine cavity is clearly demonstrated. Magnetic resonance imaging (MRI) images of the lesion (short arrows) (D-F).

Figure 2

Computed tomography, ultrasound and magnetic resonance images of lipomatous uterine tumor in a 61-year-old woman. A: Computed tomography axial image of the pelvis with no contrast shows a hypodense lesion in the uterine fundus with thin internal septa (long arrow); B: Ultrasound in longitudinal view reveals a rather homogeneous and hyperechoic lesion (asterisk) in the uterus, just superior to the urinary bladder; C-F: Magnetic resonance imaging (MRI) images of the lesion. T1-weighted MRI images in axial plane (C) and in sagittal plane (D) show a T1 hyperintense lesion in the uterine fundus with thin hypointense septa (short arrows); E: Suppression of signal is seen in the T1-weighted fat-suppressed sequence, suggestive of fatty component of the lesion; F: Thin enhancing septa are seen inside the lesion after gadolinium contrast is administered.

Figure 3

Computed tomography images of uterine lipoma in a 72-year-old woman. A and B: Axial computed tomography images without contrast (A) and after intravenous contrast (B) show a non-enhancing hypodense lesion (long arrows) in left side of the uterine fundus. Small amount of soft tissue density (short arrows) is noted inside the lesion; C and D: Coronal (C) and Sagittal (D) reformatted images also reveal the relationship of the lesion with the uterus.