Giant cell
tumor of
bone
Giant cell
tumor of the
bone (also
called giant
cell myeloma
or
osteoclastoma)
is a
relatively
uncommon
tumor. It is
characterized
by the
presence of
multinucleated
giant cells
(osteoclast-like
cells).
These tumors
are
generally
benign. In
most
patients,
the tumors
are slow to
develop, but
may recur
locally in
as many as
50% of
cases.
Metastasis
to the lungs
may occur.
Epidemiology
Giant cell
tumor of the
bone
accounts for
4-5% of
primary bone
tumors and
18.2% of
benign bone
tumors (Gamberi
et al,
2003). Giant
cell tumors
are mostly
benign,
however
5-10% of
patients may
have a
malignant
tumor.
Clinical
characteristics
Patients
usually
present with
pain and
limited
range of
motion
caused by
tumor's
proximity to
the joint
space. There
may be
swelling as
well, if the
tumor has
been growing
for a long
time. Some
patients may
be
asymptomatic
until they
develop a
pathologic
fracture at
the site of
the tumor.
Imaging
On x-ray,
giant cell
tumors (GCTs)
have a
metaepiphyseal
location and
grow to the
articular
surface of
the involved
bone (Murphey
et al,
2001). They
are
distinguishable
from other
bony tumors
in that GCTs
usually have
a
non-sclerotic
and sharply
defined
border.
Because
giant cell
tumors are
known to
metastasize,
when the
diagnosis of
giant cell
tumor is
suspected, a
chest x-ray
or CT may be
needed. MRI
can be used
to assess
intramedullary
and soft
tissue
extension.
Treatment
Surgery is
the
treatment of
choice if
the tumor is
determined
to be
resectable.
Patients
with tumors
that are not
amenable to
surgery are
treated with
radiation
therapy
(Mendenhall
et al,
2006). The
situation is
complicated
in a patient
with a
pathological
fracture. It
may be best
to
immobilize
the affected
limb and
wait for the
fracture to
heal before
performing
surgery.
Other bone
tumors with
giant cells
A number of
tumors have
giant cells,
but are not
true benign
giant cell
tumors.
These
include,
aneurysmal
bone cyst,
chondroblastoma,
simple bone
cyst,
osteoid
osteoma,
osteoblastoma,
osteosarcoma,
giant cell
reparative
granuloma,
and brown
tumor of
hyperparathyroidism. |
