A previously healthy 11-year old girl with a 4-month history of intermittent, but progressive, left knee pain presented to our institution. The physical examination revealed slight fullness of the proximal left lower extremity compared with the right. A complete blood count and basic metabolic panel were normal. Anterioposterior and lateral radiographs of the left knee were performed (Figure 1) followed by magnetic resonance imaging (MRI) of the left knee (Figure 2).
Scott D. Kendell, MD
Mark S. Collins, MD
, Department of Radiology, Mayo Clinic, Rochester, MN. Dr.
Kendell is now at Duke University Medical Center, Durham,
A previously healthy 11-year old girl with a 4-month history of
intermittent, but progressive, left knee pain presented to our
institution. The physical examination revealed slight fullness of
the proximal left lower extremity compared with the right. A
complete blood count and basic metabolic panel were normal.
Anterioposterior and lateral radiographs of the left knee were
performed (Figure 1) followed by magnetic resonance imaging (MRI)
of the left knee (Figure 2).
Anteroposterior and lateral radiographs of the left knee
revealed a predominantly lytic, permeative lesion in the proximal
tibial metaphysis with a wide zone of transition and cortical
destruction along the lateral margin of the lesion (Figure 1).
Selected T1- and T2-weighted coronal and axial MR images of the
proximal left tibia revealed a 5-cm mass located eccentrically
within the lateral aspect of the proximal tibial metaphysis (Figure
2). The mass contained multiple fluid-fluid levels. There was
cortical disruption along the posterolateral aspect of the proximal
tibia with extension of the mass into the adjacent soft
Telangiectatic osteosarcoma is a rare malignant osteogenic
first described a case of telangiectatic osteosarcoma in 1854, but
it was Ewing,
in 1922, who formally classified the tumor as a distinct histologic
subtype of osteosarcoma.
In a large series of bone tumors at the Mayo Clinic,
telangiectatic osteosarcoma represented 3.5% of all osteosarcomas
and 0.7% of all malignant bone tumors.
The tumor is seen slightly more often in males (3:2 male:female
ratio) and occurs most frequently in the second decade of life, but
can be seen over a large age range.
Similar to conventional osteosarcoma, the majority of lesions are
metaphyseal and located around the knee (distal femur, proximal
tibia). The pelvis, scapula, ribs, and skull are less common
locations for telangiectatic osteosarco-
There are reports of telangiectatic osteosarcoma as a secondary
tumor in Paget's disease
and a case of telangiectatic dedifferentiation of a parosteal
One case of multicentric telangiectatic osteosarcoma has also been
Telangiectatic osteosarcoma can rarely occur as an extraskeletal
Conventional radiographs of patients with telangiectatic
osteosarcoma typically reveal a lucent lesion with a wide zone of
transition. Aggressive radio-graphic features, such as periosteal
reaction, cortical destruction, pathologic fracture, and
soft-tissue mass are also common findings. Consistent with the
cystic nature of the tumor, the computed tomographic (CT)
attenuation of the central portion of the lesion can be lower than
that of soft tissue, and bone scintigraphy often shows increased
radiotracer uptake peripherally in the tumor with central
photopenia (known as the donut sign).
Fluid-fluid levels are often seen on CT and magnetic resonance
imaging (MRI), but these are not entirely specific for
Hemorrhage is frequently observed in association with the tumor as
high signal intensity on T1- and T2-weighted images.
Differential considerations for telangiectatic osteosarcoma
during the radiographic evaluation include aneurysmal bone cyst,
giant cell tumor, Ewing's sarcoma, angiosarcoma, and solitary bone
cyst. Murphey et al
have reported that when subtle osteoid formation is seen in the
peripheral portion of the tumor on CT or when enhancement with
intravenous contrast is seen on CT or MRI in the same region,
telangiectatic osteosarcoma can be differentiated from aneurysmal
bone cyst, which is the lesion most often confused with
The prognosis for telangiectatic osteosarcoma was previously
thought to be poor. In 1976, Matsuno et al
reported on 25 patients at the Mayo Clinic and found that 24 of
those patients were dead within 8.5 years. Mervak et al
updated the Mayo Clinic experience in 1991 and reported that the
prognosis for telangiectatic osteosarcoma was not significantly
different from conventional osteosarcoma.
Other studies have also concluded that the 5-year survival for
patients with telangiectatic osteosarcoma is the same as that for
patients with conventional osteosarcoma.
Treatment of telangiectatic osteosarcoma consists of
chemotherapy followed by wide surgical resection, similar to that
of conventional osteosarcoma.
Telangiectatic osteosarcoma is a rare malignant bone tumor. The
location, prognosis, and treatment of this unusual lesion mirror
that of conventional osteosarcoma. Fluid-fluid levels and areas of
hemorrhage are typically seen on MRI along with aggressive
radiographic features, such as periosteal reaction, wide zone of
transition, cortical destruction, and soft-tissue mass.