Primary synovial sarcoma of the gastrocolic ligament

A case of primary mesenteric synovial sarcoma: a challenging presentation

BACKGROUND

Synovial sarcoma is an uncommon soft tissue malignancy that mainly occurs near tendon sheath and bone joints. Primary intra-abdominal location is exceedingly rare and characterized by non-specific clinical signs.

CASE PRESENTATION

We report the case of a young female without medical history who presented with acute abdominopelvic pain. Ultrasound echography revealed a right mass measuring 7 cm in greater diameter cystic with solid areas, likely of ovarian origin. A coelioscopy with peritoneal biopsies was performed. Histological examination with immunohistochemistry concluded the diagnosis of GIST. The patient was referred to the surgery department and after laboratory routine analysis and computed tomography, the patient was proposed to surgical management. Per-operative findings revealed a mesenteric mass locally invading the greater omentum and the appendicular wall. Pathological examination with immunochemistry confirmed the diagnosis of mesenteric monophasic synovial sarcoma invading the appendicular wall with positive surgical margins. Chemotherapy was proposed with a good response. Our patient is free from disease 9 months later.

CONCLUSIONS

We aimed through this case report to discuss mesenteric presentation monophasic SS, mimicking ovarian malignancy, emphasizing clinicopathological features and differential diagnoses.

The Biology of Synovial Sarcoma: State-of-the-Art and Future Perspectives

New molecular insights are being achieved in synovial sarcoma (SS) that can provide new potential diagnostic and prognostic markers as well as therapeutic targets. In particular, the advancement of research on epigenomics and gene regulation is promising. The concrete hypothesis that the pathogenesis of SS might mainly depend on the disruption of the balance of the complex interaction between epigenomic regulatory complexes and the consequences on gene expression opens interesting new perspectives. The standard of care for primary SS is wide surgical resection combined with radiation in selected cases. The role of chemotherapy is still under refinement and can be considered in patients at high risk of metastasis or in those with advanced disease. Cytotoxic chemotherapy (anthracyclines, ifosfamide, trabectedin, and pazopanib) is the treatment of choice, despite several possible side effects. Many possible drug-able targets have been identified. However, the impact of these strategies in improving SS outcome is still limited, thus making current and future research strongly needed to improve the survival of patients with SS.

Primary renal synovial sarcoma presenting with a retroperitoneal bleed

Synovial sarcomas are most commonly localised in extremities, especially in the lower thigh and knee areas. Comprising less than 1% of all malignancies, retroperitoneal synovial sarcoma is very rare with primary synovial sarcoma of the kidney being even more infrequent and difficult to diagnose. We describe a case report of a renal synovial sarcoma in a young adult who was initially managed as a case of Wunderlich's syndrome secondary to what was believed to be a ruptured renal angiomyolipoma. After biopsy confirmation, the patient was eventually managed with neo-adjuvant chemotherapy followed by a right radical nephrectomy and right hepatectomy. Despite its rarity, synovial sarcoma should be considered as differential diagnosis of a bleeding retroperitoneal soft tissue mass detected in young adults.

Monophasic synovial sarcoma of the greater omentum: case report and review of literature

Synovial sarcoma is a malignant spindle cell neoplasm normally arising from tissues around joints, bursa and tendon sheaths. Several reports involving the gastrointestinal tract, mainly the oesophagus and stomach, have been documented; however, the omentum remains an extremely unusual location. Monophasic type is composed exclusively of spindle cells arranged in fascicles. Establishing the correct diagnosis of these tumours could be challenging because of the similarities with gastrointestinal stromal tumours and other mesenchymal tumours with similar histology.

Primary malignant tumors of peritoneal and retroperitoneal origin: clinical and imaging features

Peritoneal carcinomatosis and metastatic involvement of the retroperitoneum are manifestations of many organ-based malignancies and lymphoproliferative disorders. Primary malignancies of peritoneal and retroperitoneal origin occur much less frequently, and are difficult to distinguish from metastatic disease on imaging alone. However, the imaging features of these primary tumors, taken in concert with the clinical data, can be helpful in narrowing the scope of the differential diagnosis. This review presents the clinical and imaging features of primary peritoneal and retroperitoneal tumors arising from the various tissue components that comprise the ligaments, mesenteries, and connective tissues of the peritoneal and retroperitoneal spaces.

From the archives of the AFIP: Imaging of synovial sarcoma with radiologic-pathologic correlation

Synovial sarcoma is the fourth most common type of soft-tissue sarcoma, accounting for 2.5%-10.5% of all primary soft-tissue malignancies worldwide. Synovial sarcoma most often affects the extremities (80%-95% of cases), particularly the knee in the popliteal fossa, of adolescents and young adults (15-40 years of age). Despite its name, the lesion does not commonly arise in an intraarticular location but usually occurs near joints. Histologic subtypes include monophasic, biphasic, and poorly differentiated; the cytogenetic aberration of the t(X;18) translocation is highly specific for synovial sarcoma. Although radiographic features of these tumors are not pathognomonic, findings of a soft-tissue mass, particularly if calcified (30%), near but not in a joint of a young patient, are very suggestive of the diagnosis. Cross-sectional imaging features are vital for staging tumor extent and planning surgical resection; they also frequently reveal suggestive appearances of multilobulation and marked heterogeneity (creating the "triple sign") with hemorrhage, fluid levels, and septa (creating the "bowl of grapes" sign). Two features associated with synovial sarcoma that may lead to an initial mistaken diagnosis of a benign indolent process are slow growth (average time to diagnosis, 2-4 years) and small size (< 5 cm at initial presentation); in addition, these lesions may demonstrate well-defined margins and homogeneous appearance on cross-sectional images. Synovial sarcoma is an intermediate- to high-grade lesion, and, despite initial aggressive wide surgical resection, local recurrence and metastatic disease are common and prognosis is guarded. Understanding and recognizing the spectrum of appearances of synovial sarcoma, which reflect the underlying pathologic characteristics, improve radiologic assessment and are important for optimal patient management.

Primary intra-abdominal synovial sarcoma

We report a case of primary intra-abdominal synovial sarcoma of the omentum in a 66-year-old man hospitalized for intermittent abdominal fullness for 1-2 months and tenesmus for 2 weeks. The patient had a palpable mass that was solid, hard and with well-defined thickness within his abdomen. A huge heterogeneous mass lesion over the middle abdomen that started from S2, S3 of the liver to the transverse colon was shown on abdominal computed tomography. The major cell types of the tissue mass were confirmed to be spindle and epithelial cells, which was consistent with biphasic synovial sarcoma according to pathologic and immunohistochemical findings.

[Primary retroperitoneal synovial sarcoma revealed by hemorrhagic shock]

INTRODUCTION

Primary retroperitoneal synovial sarcoma is a rare malignant neoplasm that typically arises in young adults. We report here an unusual presentation of this tumor during hemorrhagic shock and retroperitoneal hematoma.

CASE

A 31-year-old man was admitted complaining of acute violent pain of the right lower abdominal quadrant. Physical examination was normal. The computed tomography scan showed a heterogeneous retroperitoneal mass near the iliac bifurcation, with a diameter of 3 cm and spontaneous contrast. The tumor ruptured shortly afterwards and the patient underwent emergency surgery for hemorrhagic shock and retroperitoneal hematoma. No metastases were observed. Although six cycles of doxorubicin and ifosfamide led to initial clinical and tomographic remission, relapse occurred 17 months later.

DISCUSSION

Only 20 cases of primary retroperitoneal synovial sarcoma have been described. They are most often discovered following abdominal pain or anemia. Tumor rupture with retroperitoneal hematoma has not previously been reported. Surgical ablation remains the basis for management of this tumor, and survival appears to depend on its quality. Prognosis is poor. Our case is original by the tumor's location and mode of discovery.

Primary neoplasms of peritoneal and sub-peritoneal origin: CT findings

Peritoneal carcinomatosis is a common metastatic manifestation of many organ-based malignancies, particularly carcinomas of the gastrointestinal tract and ovaries. Primary neoplasms of peritoneal and sub-peritoneal origin occur much less frequently than metastatic peritoneal involvement from a known or occult primary tumor; however, these rare primary lesions (peritoneal mesothelioma, papillary serous carcinoma, desmoplastic small round cell tumor, benign and malignant mesenchymal tumors, lymphoproliferative disorders) are often first detected at computed tomography (CT) and should be considered in the absence of a known or suspected organ-based malignancy. A precise diagnosis based on imaging findings alone is often not possible. Furthermore, distinguishing a benign from a malignant process and a primary from a metastatic process is also challenging. Nevertheless, CT features combined with the patient's relevant clinical and demographic data can help narrow the differential diagnosis for a peritoneum-based neoplasm in many cases. CT is useful not only for the detection, characterization, and staging of primary neoplasms of peritoneal and subperitoneal origin, but also for guiding biopsy for tissue diagnosis.

Anterior Abdominal Wall Synovial Sarcoma

Synovial sarcoma usually arises in the extremities and in close proximity to large joints. Primary synovial sarcoma of the anterior abdominal wall is rare. A 17-year-old girl was admitted to the hospital with a palpable abdominal mass, and there was a 9.5 cm x 7.5 cm x 6-cm lobulated, cystic, and semisolid lesion of in the external oblique abdominal muscle shown on the abdominal magnetic resonance image. She was then operated and pathology was consistent with synovial sarcoma. The presence of synovial sarcoma in extraarticular sites such as the abdominal wall argues against an origin from arthrogenous mesenchyme.

Intra-abdominal synovial sarcoma: a clinicopathological study

AIMS

To evaluate a series of synovial sarcomas arising in the abdomen, pelvic cavity, or retroperitoneum. Synovial sarcoma is rare within the abdomen. In this location, it can be confused with other biphasic tumours and with other spindle and round cell sarcomas.

METHODS AND RESULTS

Cases were retrieved from archives. There were 11 intra-abdominal tumours among 300 synovial sarcomas in two referral practices (3.7%). Three were pelvic (two midline, one sidewall) and eight were retroperitoneal. They occurred in six males and five females aged from 25 to 75 years (mean 49 years, median 46 years), and ranged in diameter from 65 to 470 mm (mean 210 mm, median 150 mm). Six examples were biphasic, five were monophasic and seven had poorly differentiated areas. Monophasic tumours displayed at least one epithelial marker. One biphasic tumour had a SYT-SSX2 fusion gene. Seven sarcomas were high-grade and four of intermediate grade malignancy. Follow-up data were available in 10 patients. In all but one case, tumour recurred or metastasized within the abdomen. The pelvic sarcomas also metastasized outside the abdomen. Eight of 10 patients (80%) died of disease with survival from 4 to 36 months (mean 17 months, median 18 months). Two patients were alive with disease at 43 and 48 months.

CONCLUSIONS

Synovial sarcomas rarely arise within the abdomen and pelvis. They occur mainly in middle age, attain a large size, are difficult to excise and recur locally. Pelvic tumours metastasize distantly. Retroperitoneal tumours remain confined to the abdomen and, unlike synovial sarcomas elsewhere, do not metastasize remotely, although mortality is high.

Cystic malignant fibrous histiocytoma of the gastrocolic ligament

A case of malignant fibrous histiocytoma (MFH) of the gastrocolic ligament is presented. It appeared as a huge, thin walled cystic tumour in the upper abdominal cavity on CT. Barium studies showed splaying of the stomach and transverse colon by the mass. 1 year after resection of the cystic tumour, recurrence occurred at the greater curvature of the stomach and in the liver, with a cystic appearance similar to the primary tumour. To our knowledge, the CT appearance of primary cystic MFH of the gastrocolic ligament has not been previously documented.