Primary synovial cell sarcoma of the kidney: case report and review of the literature

Synovial Sarcoma of the Kidney: Diagnostic Pitfalls in a Case with Myxoid Monophasic Differentiation and No Epithelial Biomarkers Expression

Synovial sarcomas are soft tissue tumours of uncertain origin, most commonly found in the upper or lower extremities. They are characterised by distinctive chromosomal rearrangements involving the gene SS18. Synovial sarcomas can occasionally arise also in visceral sites, but retroperitoneal SSs are very unusual. Among them, a few primary renal synovial sarcomas have been described in the scientific literature. Primary renal synovial sarcomas tend to be monophasic and often show cystic changes. Histologically, they can closely resemble other primary kidney tumours, mainly paediatric tumours such as nephroblastoma and clear cell sarcoma of the kidney. In the current work, a primary synovial sarcoma of the kidney with unusual morphological features (extensively myxoid stroma and immunohistochemical positivity for BCOR) is described. Molecular analysis, through targeted RNA sequencing, was of invaluable help in reaching the correct diagnosis. Despite locally advanced disease at presentation, the patient showed an unexpectedly brilliant response to chemotherapy.

SS18-SSX Expression in a Contemporary Cohort of Primary Renal Synovial Sarcoma: A Multi-Institutional Experience of Fourteen Patients

Primary renal synovial sarcoma is a rare aggressive mesenchymal neoplasm of the kidney that accounts for less than 1% of renal sarcomas. Herein, we describe the clinicopathologic and molecular findings of 14 renal synovial sarcoma patients in one of the largest case series to date and to our knowledge, the only renal synovial sarcoma series to use novel SS18-SSX IHC. Clinicopathologic, IHC, molecular, management, and follow-up data were reviewed and analyzed. Macroscopically, the tumors had either homogeneous, tan-white, and solid (n = 10), variegated and solid (n = 3), or variegated and solid-cystic (n = 1) cut surfaces. Spindle cell (n = 10), round cell (n = 3), and round to epithelioid morphologies (n = 1) were observed. SS18-SSX IHC was positive in all 14 tumors (diffuse, n = 10; multifocal, n = 2; focal, n = 2). All the tumors harbored SS18::SSX1/2 gene rearrangement. Metastases to the liver, brain, and lung (n = 1); liver and bone (n = 1); liver and diaphragm (n = 1) were identified. Adjuvant chemotherapy was administered in 11/12 patients. Follow-up was available for 10 patients (time period range: 5 to 24 months). Four patients died of disease, and six patients are alive with no recurrence or metastasis. As SS18-SSX IHC showed an excellent concordance with the FISH results, this may reliably be used in the IHC panel of spindle/round cell sarcomas of the kidney and as a molecular surrogate for renal synovial sarcoma, particularly in a resource-limited setting. Also, the tumors with focal SS18-SSX expression had lower break apart signals in the FISH assay (19% and 23% in two tumors with focal SS18-SSX IHC positivity).

Primary Synovial Sarcoma of the Kidney: Diagnostic Approach and Therapeutic Modalities for a Rare Nosological Entity

Synovial sarcoma (SS) is a rare mesenchymal entity that represents 5–10% among soft tissue sarcomas (STS). Primary renal synovial sarcoma (PRSS) is an uncommon, rapidly growing tumor, with potential metastatic dissemination. The main prognostic factors of PRSS include tumor size and histologic grade, while translocation t (X; 18) (p11.2; q11.2) (fusion of SYT gene -chromosome 18- with SSX genes (1, 2 or 4)-chromosome X) is the most common pathognomonic sign. Aggressive surgical resection of the tumor along with concomitant regional lymphadenectomy is the treatment of choice for PRSS, while additional en bloc resection of the adjacent affected organs is often performed. To date, the role of preoperative or postoperative chemotherapy remains equivocal. The prognosis of patients with PRSS is poor, as the 5-year survival rate is only 20–30% and further deteriorates when a high mitotic activity is detected. Local recurrence even after complete R0 surgical excision remains the most frequent cause of death. The aim of this review was to meticulously discuss clinical features, histogenesis, and morphological and immunochemical findings of PRSS, while the role of current diagnostic and therapeutic management of this aggressive neoplasm was emphasized.

Primary Renal Synovial Sarcoma and Clinical and Pathological Findings: a Systematic Review

PURPOSE OF REVIEW

To update epidemiological, diagnostic, and therapeutic information on primary synovial sarcoma of the kidney.

RECENT FINDINGS

A total of 96 studies were analyzed; age at presentation was 38.6±14.2 years, predominant location of tumor was right kidney; frequent reported symptoms at diagnosis were hematuria and pain. For definitive diagnosis, cytogenetic technique was used. Detected oncogene was available in 37.8% cases with fusion of SS18-SSX in most patients. Surgery is treatment of choice, with adjuvant chemotherapy; most frequently ifosfamide-based associated with doxorubicin or epirubicin. Overall median survival was 34 months. Mortality was 29% of the cases which reported death and the recurrence rate was 39.8%. Risk of death was increased in patients with metastases at diagnosis Primary RSS occurs more often in young men. RSS often presents with symptoms and in an advanced stage. Surgical treatment is the most commonly used and chemotherapy for advanced or recurrent treatment.

Primary synovial sarcomas in the paediatric and young adult population: A pictorial review

PURPOSE

To present a pictorial essay of paediatric primary synovial sarcomas from common and less documented anatomical locations. To review the literature for the imaging characteristics and prognostic factors of this rare but important childhood malignancy.

METHOD

24 primary synovial sarcoma cases (17 male, 7 female with an age range 4-21 years) were reviewed in a collaborative effort between St Jude Children's Research Hospital and Great Ormond Street Hospital for Children. Images from 19 cases were selected for inclusion, to demonstrate the spectrum of appearances across imaging modalities, in a range of different anatomical locations (upper limb, lower limb, chest/abdomen/pelvis, and head and neck). A literature review depicting the typical radiological features and the prognostic significance of these features, was also conducted.

RESULTS AND CONCLUSIONS

Primary synovial sarcoma can occur in any anatomical location, but typically within the extremities and often in close association with joints. Rarer anatomical locations described in our essay include the gastrohepatic ligament and femoral nerve sheath. We detail the salient imaging characteristics, including the T2 'triple signal' pattern which is believed to be highly specific for this particular sarcoma and in many cases predicts a poor outcome. Other poor prognostic factors include haemorrhage, lack of calcification and tumour size >10 cm. A broad range of radiological appearances are described, and in some cases related to anatomical position and size, however the presence of a soft tissue mass close to a joint in a young patient are suggestive of this diagnosis.

Primary renal synovial sarcoma: two cases and review of the literature

OBJECTIVE

To investigate the clinicopathological features, treatment, and prognosis of primary renal synovial sarcoma.

METHOD

Retrospectively collected and analyzed clinical and pathological data of two cases of patients with renal primary synovial sarcoma, and reviewed domestic and foreign related literature.

RESULTS

The first patient was admitted for progressive enlargement of a left renal mass, then she underwent a radical resection of left kidney and adrenal gland, and the final diagnosis was primary renal synovial sarcoma. However, the tumor progressed with multiple nodules in the left peritoneal retroperitoneal space and abdominal wall 3 months later. The second patient was hospitalized for a left lung mass and left renal mass after 3 months. She received left nephrectomy and left lower lobectomy. The final diagnosis was primary renal synovial sarcoma with extensive metastasis in both lungs and pelvic and abdominal cavity. The patient underwent chemotherapy and targeted therapy after operation, and died because of tumor burden after 23 months.

CONCLUSION

Primary renal synovial sarcoma is a rare soft tissue tumor in the kidney with a poor prognosis. An accurate diagnosis needs consideration of the morphology, immunohistochemistry, and SYT-SSX gene results. Clinically, radical nephrectomy is the main strategy, and adjuvant ifosfamide-based chemotherapy after operation has benefits.

Primary synovial sarcoma of the kidney: a case report of complete pathological response at a Lebanese tertiary care center

Background

Primary synovial sarcoma of the kidney is a rare type of soft tissue sarcoma. Its presenting features can resemble those of other renal tumors; rendering its early diagnosis, a dilemma. Several cases of renal synovial sarcoma have been reported in the literature with varying treatment options and outcomes. This article describes a rare case of primary renal synovial sarcoma and reviews all cases in the literature.

Case presentation

A 26-year-old male presented with flank pain and hematuria. Initially diagnosed with Wilm’s tumor, revision of pathology and histology, along with the immunohistochemical profile, confirmed, nevertheless, the diagnosis of primary monophasic synovial sarcoma of the kidney with the SYT-SSX2 fusion transcript. Follow-up, post nephrectomy, revealed recurrence within the lungs and at the surgical bed. Surgical resection followed by adjuvant chemotherapy regimen constituting of Doxorubicin and Ifosfamide, achieved complete pathological response.

Conclusion

In this case report, we emphasize the need for accurate diagnosis and prompt treatment. We propose multimodality treatment approach including surgery along with anthracycline-based chemotherapy to induce complete remission.