J. HECKMAN ET AL.
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The patient was referred to a medical oncologist and
radiation oncologist for additional evaluation and treat-
ment. A staging work-up, including a chest radiograph
and computed tomography (CT) scan, demonstrated
prominent bilateral axillary lymph nodes but no evidence
of metastatic disease. Staging identified the lesion as a
T2b N0 M0 synovial cell carcinoma. Due to the lesion
size, the patient was determined to be at high risk for
recurrence. As such, the patient was subsequently treated
with a combination of adjuvant chemotherapy and radia-
tion. Four cycles of ifosfamide and doxorubicin, which
were tolerated well, were initiated prior to radiation
therapy.
3. Discussion
Synovial sarcomas are rare malignant tumors historically
regarded as high grade malignancies with significant
metastatic risk. Synovial sarcoma accounts for 6-10% of
all adult soft tissue sarcomas, rendering it the fourth most
common type of sarcoma. Despite its name, this tumor is
uncommon in joint cavities, instead occurring primarily
in periarticular regions of extremities and often associ-
ated with tendon sheaths, bursae, and joint capsules.
Principally affecting young adults aged 15-40 years, with
the median age of patients in the third decade of life,
synovial sarcoma most commonly presents as a palpable,
deep-seated swelling or mass associated with pain or
tenderness. The extremity is the most common site of
primary disease, and the tumor tends to grow insidiously,
frequently delaying diagnosis and therapy. [1,2]
Definitive diagnosis is often deferred until histopa-
thologic examination of the surgical specimen upon re-
section. Pre-operative radiographs may exhibit calcifica-
tions within the tumor. Synovial sarcomas frequently
appear as round or oval, lobulated, in close association
with a large joint, and without involvement of the under-
lying bone. Computed tomography (CT) and magnetic
resonance imaging (MRI) may be utilized in further elu-
cidating the site of origin and extent of the mass. Syno-
vial sarcoma represents a malignancy of two morpho-
logically distinct cell types that form a characteristic bi-
phasic pattern: epithelial cells and fibrosarcoma-like
spindle cells. Synovial sarcomas may be classified into
biphasic variant, monophasic fibrous variant, monopha-
sic epithelial variant, and poorly differentiated variant.
Large studies, however, have not demonstrated his-
tologic type to be of prognostic or therapeutic signify-
cance. [3] Immunohistochemical stains further aid in the
diagnosis of synovial sarcoma, the most useful of which
are epithelial markers, including pankeratin, CAM 5.2,
and EMA, as identified in our patient. These markers are
less apparent in the spindle cell component of these tu-
mors, leading to the distinctive patchy staining pattern
found in synovial sarcoma. In addition, in accordance
with our findings, synovial sarcoma stains positively for
bcl-2 and is consistently negative for CD34. Cytogenetic
studies also indicate the presence of a translocation be-
tween chromosomes X and 18, t(X; 18) (p11.2; q11.2), in
nearly all (>90%) cases of synovial sarcoma. This char-
acteristic translocation involves the SYT gene on chro-
mosome 18 and the SSX1 and SSX2 genes, located on
the X chromosome, and leads to the creation of abnormal
fusion proteins. [4]
Synovial sarcoma traditionally carries a poor progno-
sis. [3] In a retrospective analysis of synovial sarcoma in
patients of all ages, Ferrari et al. [5] determined survival
rates to vary significantly, measuring 5-year event-free
survival to be 37 % for the study cohort as a whole, with
the rate varying with age (66%, 40%, and 31% for pa-
tients age ≤16, 17-30, and >30 years, respectively).
0Large tumor size has been consistently shown to be
related to the progression to distant metastasis and de-
creased disease specific survival, and most studies dem-
onstrate that prognostic indicators of distant recurrence
parallel survival. [4] In a multivariate analysis of prog-
nostic factors, Lewis et al. [6] demonstrated tumor size
≥5 cm and invasion of bone and neurovascular structures
to be the only independent adverse predictors of distant
recurrence and mortality.
Complete surgical resection remains the foundation of
treatment for synovial sarcoma. Despite the frequent
close proximity of the tumor to neurovascular structures,
en bloc resection of the tumor is standard and these
structures are usually spared. Adequate margins require
that the resected specimen be tumor free at the margins,
preferably with a margin of normal tissue. There is no
role for non-curative surgery. [4] Achieving adequate
surgical margins, however, must be balanced with
maximal preservation of function and minimal morbidity.
[3] Surgery is also the mainstay of treatment for locally
recurrent disease. The role of surgery in treating metas-
tatic synovial sarcoma is less well defined and limited to
selected patients based on disease extent, length of dis-
ease-free interval, and response to systemic chemother-
apy. [4]
Beyond surgery, the optimal therapeutic approach to
synovial sarcoma has not yet been definitively estab-
lished. However, prognosis is poorest in patients treated
only with local excision with inadequate margins and no
adjunctive therapy, with recurrence rates recorded as
high as 70-83%. [2] As in the management of other soft
tissue sarcomas, there is a role for adjuvant radiation
therapy. Although good local control can be accom-
plished through surgery and radiation therapy, distant
metastasis remains the limiting factor with regard to the