Primary renal synovial sarcoma: A case report

Abstract

BACKGROUNDSynovial sarcoma, a rare mesenchymal tumor type with unclear histological origin and direction of differentiation, accounts for 6%–10% of soft tissue tumors. It is mainly located near the joints and tendons of the limbs, and occurs primarily in children or young adults. Primary renal synovial sarcoma (PRSS) is very rare, accounting for approximately 1% of synovial sarcomas. It is a spindle cell tumor type affecting mesenchymal tissue, and has morphological, genetic, and clinical characteristics, and a certain degree of epithelial differentiation. It is highly malignant and has the fourth highest incidence among soft tissue sarcomas. Here, we report a case of PRSS and share some valuable information about the disease.CASE SUMMARYA 54-year-old male patient was admitted to the hospital for a space-occupying lesion in the right kidney for 2 d upon ultrasound examination. The patient had no cold or fever; no frequency, urgency or pain of urination; and no other discomfort. The results of a hemogram, blood biochemistry, and tumor markers were in the normal range. The patient was examined by computed tomography (CT), which indicated the presence of a soft tissue density shadow with a diameter of approximately 6.8 cm in the right renal pelvis area, showing uneven enhancement. Ultrasound indicated a cystic solid mass of approximately 6.8 cm × 6.5 cm in the right kidney, with an unclear boundary and irregular shape. Meanwhile, color Doppler flow imaging showed dotted blood flow signals in the periphery and interior. Contrast-enhanced ultrasound (CEUS) showed "slow in and fast out" hyperenhancement of the right renal mass after contrast agent injection. The postoperative pathological diagnosis was (right kidney) synovial sarcoma. Despite postoperative adjuvant chemotherapy, tumor recurrence was detected two years later.CONCLUSIONPRSS is a rare malignant tumor. To date, no characteristic imaging findings have been observed. The diagnosis is confirmed primarily through postoperative pathological immunohistochemistry and SS18 (SYT) gene detection. In this case, CEUS was used preoperatively. We found that PRSS has the characteristic of "slow in and fast out" hyperenhancement, and its particular characteristics have diagnostic value. Postoperative adjuvant chemotherapy is not very effective.

Primary renal synovial sarcoma

“…Postoperative chemotherapy is commonly used, but the effect of chemotherapy is not satisfactory, and recurrence was reported within 3 years. [ 17 ] Targeted therapy has also been tested and found to be successful. [ 18 ]…”

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

“…Tumors reported in the literature ranged in age from 4 to 76 years with a median of 36.2 years. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] In published cases, 3% of patients were younger than 18 years of age which is less than in our cohort. There is a slight male predominance both in published cases (M: F = 1.14:1) and in our cohort (1.8:1).…”

“…5,6 Primary renal synovial sarcoma is one of the rarest types of sarcomas of kidney and comprises 2% of all malignant renal tumors and 1% of all synovial sarcomas across the anatomic sites. 7 The first case of primary renal synovial sarcoma was reported by Argani et al in 2000 and to date, 88 case reports and 23 case series, [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] with only two case series consisting of more than 14 tumors, have been reported in the literature. 8,9 The most common presenting symptoms include hematuria, pain, and palpable mass.…”

Two Cases of Biphasic Synovial Sarcoma With Expression of PAX8 and ER: A Diagnostic Pitfall

“…To date, only limited publications in the English literature reported PAX8 positivity in SSs, with most cases of renal origin (12,14,18), 1 case of sub-diaphragm location (13) and 1 case in the wrist (19). PAX-8 and ER expression in SS from the current English literature review are summarized in Table 2.…”