Ashish Chawla, MD, Ajay Thakker, MD, Hemant Telkar,
Nikhil Kamat, MD
from the Jupiter Scan Centre, Mumbai, India; and
Krantikumar Rathod, MD, Abhijit Raut, MD,
Ashwin Garg, DNB
from the Department of Radiology, King Edward Memorial VII
Hospital, Parel, Mumbai, India.
A 65-year-old postmenopausal woman, gravida 2, para 2, presented
with leucorrhoea and mild pelvic discomfort. Physical examination
revealed a palpable lump arising from her pelvis. Pelvic ultrasound
was performed (Figure 1).
Pelvic ultrasound demonstrated a large, well-defined,
hyperechoic mass, measuring 9.9 × 9.9 × 8.9 cm related to the
anterior wall of the uterus (Figure 1). Multiple small hypoechoic
intramural leiomyomas were also seen. The ovaries could not be
identified separate from the mass. In view of these findings,
magnetic resonance imaging (MRI) was performed with a 0.5T unit (GE
Signa Contour, GE Medical Systems, Milwaukee, WI). MRI showed a
large lobulated mass arising from the anterior wall of the uterus,
which had hyperintense signals on T1-weighted spin echo (SE) images
(repetition time [TR] 420, echo time [TE] 12), which suppressed on
a fat-saturation sequence (Figures 2A and 2B). On T2-weighted fast
spin-echo (FSE) images (TR 4800, TE 88), the mass appeared
inhomogeneous and hyperintense with chemical shift artifact,
further suggesting fat content within the mass (Figure 2C).
A subsequent CT scan (GE Dxi/Hi speed) revealed a predominantly
fat-containing uterine mass with strands of isodense soft tissue
(Figure 3). A preoperative diag-nosis of uterine lipoleiomyoma was
The patient underwent a total abdominal hysterectomy. Gross
pathologic examination of the uterus revealed a large,
well-circumscribed, solid mass with a yellowish cut surface, mixed
with few gray areas. Histopathologic evaluation identified mature
adipose tissue and smooth muscle, which are consistent with
A lipoleiomyoma is an uncommon benign uterine neoplasm. To date,
only 9 cases have been published in imaging literature. MRI
findings have been described in only 4 cases.
Lipoleiomyomas are composed of mature smooth muscle, fat, and
These masses are similar to uterine leiomyomas, in both clinical
presentation and course.
Lipomatous uterine tumors are typically found in postmenopausal
women and are associated with leiomyomas.
They usually occur in corpus, predominantly intramurally; however,
they may be subserosal.
A case of ovarian lipoleiomyoma has also been reported.
The histologic spectrum includes lipoma, lipoleiomyoma, and
The masses may be endophytic or exophytic, with respect to the
Because fat tissue is not native to the myometrium, various
theories have been proposed for the histogenesis of these tumors. A
histopathologic study suggested that fatty metamorphosis of smooth
muscle cells of a leiomyoma is the most likely etiologic factor in
the formation of adipose tissue, rather than fatty degeneration.
The differential diagnosis of the lipomatous mass in the pelvis
includes: benign cystic ovarian teratoma, malignant degeneration of
cystic teratoma, nonteratomatous lipomatous ovarian tumor, benign
pelvic lipoma, liposarcoma,
and lipoblastic lymphadenopathy.
Since an asymptomatic lipoleiomyoma requires no treatment and is
clinically similar to a leiomyoma, it is important to differentiate
these tumors from ovarian teratomas, which require surgical
However, associations of lipomatous uterine tumors and endometrial
carcinomas with lipoleiomyosarcomas arising in uterine
lipoleiomyomas have been reported.
A uterine lipoleiomyoma usually appears as a well-defined
hyperechoic mass encased by a hypoechoic ring on ultrasound. This
ring represents a layer of myometrium surrounding the lipomatous
In the cases of a large mass, as in the present case, ultrasound
may not be able to identify the exact organ of origin. CT shows
more specific findings, revealing a predominantly fatty mass with
areas of nonfat soft-tissue density arising from the uterus.
MRI is highly specific, delineating fat tissue as hyper-intense on
Tl- and T2-weighted images, with chemical shift artifact.
Further confirmation of the fatty component may be done using
Although contrast-enhanced CT and gadolinium-enhanced MRI findings
have been reported in other cases of lipoleiomyomas,
these studies were not required in the present case.
Imaging plays an important role in preoperatively identifying
the fatty nature and exact intrauterine location of a leiomyoma.
Radiologists need to be aware of this entity, which, if large in
size, can be mistaken for a more common pelvic mass, such as an
ovarian teratoma, on ultrasound. The diagnosis can be confirmed on
CT or MRI, which can specifically depict fat content within the
We describe imaging features in a case of a large intramural
uterine lipoleiomyoma. Although ultrasound is quite sensitive for
the tumor, CT and MRI are more specific. The demonstration of fat
in a mass of uterine origin is highly suggestive of a case of
lipoleiomyoma. CT and MRI are useful in differentiating uterine
lipoleiomyomas from more common fat-containing pelvic masses like
ovarian teratomas, which have an altogether different management