Intraneural Synovial Sarcoma Research Articles

Monophasic synovial sarcoma mimicking schwannoma: a case report of a rare peripheral nerve tumor and literature review

ABSTRACT Introduction Synovial sarcomas occurring as primary nerve tumors (SSPN) are rare and only 69 cases of SSPNs are reported in literature. Despite the little data available, SSPNs differ from other SSs in some distinctive aspects such as epidemiology, location, and early onset of symptoms. SSPN are consequently underdiagnosed and easily mistaken for benign or malignant peripheral nerve sheath tumors (PNST). Therefore, cytogenetic or molecular testing becomes essential in order to make a correct diagnosis. This article deals with an extremely rare case of monophasic SSPN of the posterior cords of the right brachial plexus. To our knowledge, this is only the tenth case of intraneural synovial sarcoma involving the brachial plexus. Case Presentation We report the case of a 64-year-old man, who came to our attention due to a slow-growing painful right axillary neoformation, approximately 25 mm in size. The patient did not show any neurological impairments. Ultrasonography and constrast MRI showed a heterogeneous mass arising from the posterior cord of the right brachial plexus, resembling a schwannoma. The patient underwent total resection of tumor and capsule. Histologically, a diagnosis of monophasic synovial sarcoma was made based on histologic features and the immunohistochemical profile. Conclusions We report a rare primary synovial sarcoma of the brachial plexus. Given its rarity, the diagnosis may be challenging and requires a core biopsy or the surgical specimen to permit immune-molecular analysis. Margin-free surgery is the mainstay of curative treatment, while chemo- or radiotherapy may have a role in advanced or margin-positive neoplasms.

Intraneural synovial sarcoma of median nerve

Synovial sarcomas are highly aggressive soft tissue tumour with a poor and dismal prognosis. These tumours have a high propensity for distant metastasis and local recurrence. Although originally believed to arise from synovium, these tumours have been found to occur anywhere in body [1],[2]. We report here, a case of median nerve sarcoma in a 15-year female. This is a rare tumour, which is diagnosed only after histopathological examination with only a few cases reported in the literature (Table 1). Although preoperatively tumour was thought to be a nerve sheath tumour, on histopathology analysis was found to be synovial sarcoma. Despite aggressive behaviour, wide local excision is recommended even in smaller lesions. So, the diagnosis should always be kept in differentials of nerve sheath tumour, as what may be a synovial sarcoma.

Intraneural synovial sarcoma of median nerve

Synovial sarcomas are highly aggressive soft tissue tumour with a poor and dismal prognosis. These tumours have a high propensity for distant metastasis and local recurrence. Although originally believed to arise from synovium, these tumours have been found to occur anywhere in body1,2. We report here, a case of median nerve sarcoma in a 15-year female. This is a rare tumour, which is diagnosed only after histopathological examination with only a few cases reported in the literature (Table 1). Although preoperatively tumour was thought to be a nerve sheath tumour, on histopathology analysis was found to be synovial sarcoma. Despite aggressive behaviour, wide local excision is recommended even in smaller lesions. So, the diagnosis should always be kept in differentials of nerve sheath tumour, as what may be a synovial sarcoma.

Intraneural synovial sarcoma of the tibial nerve

Synovial sarcomas are malignant soft tissue tumors that carry a metastatic potential and portend poor prognoses. We report a very rare synovial sarcoma arising from the tibial nerve and describe its successful treatment including limb preservation. To the best of our knowledge, this is the 40th reported incident of intraneural synovial sarcoma, and only the fourth arising from the tibial nerve. Extensive resection of synovial sarcoma arising in the popliteal region is difficult, particularly when limb preservation is desired. Ours is the first reported patient treated for tibial nerve-derived synovial sarcoma whose limbs were preserved.

Intraneural Synovial Sarcoma of the Digital Nerve in a Hand: A Case Report and Review of the Literature.

Kim, Jeong Hwan MD1; Lee, Hyuk Jin MD, PhD1; Han, Ilkyu MD, PhD1; Ha, Jae Hong MD1; Baek, Goo Hyun MD, PhD1 Author Information

Diagnostic utility of SOX10 to distinguish malignant peripheral nerve sheath tumor from synovial sarcoma, including intraneural synovial sarcoma

Synovial sarcoma and malignant peripheral nerve sheath tumor pose a significant diagnostic challenge given similar histomorphology. The distinction is further complicated by similar immunophenotype and especially by occasional synovial sarcomas that present as intraneural tumors. Although the presence of a t(X;18) rearrangement or expression of TLE1 can help confirm the diagnosis of synovial sarcoma, negative results for these tests are not diagnostic of malignant peripheral nerve sheath tumor. The SOX10 transcription factor, a putative marker of neural crest differentiation, may have diagnostic utility in this differential, but immunohistochemical data are limited. The goal of the present study was to determine the diagnostic utility of SOX10 to discriminate between synovial sarcoma and malignant peripheral nerve sheath tumor. Forty-eight cases of malignant peripheral nerve sheath tumor, all from patients with documented neurofibromatosis, and 97 cases of genetically confirmed synovial sarcoma, including 4 intraneural synovial sarcomas, were immunohistochemically stained for SOX10. The stain was scored for intensity and fraction of cells staining. Thirty-two of 48 malignant peripheral nerve sheath tumors (67%) were SOX10-positive. The majority of malignant peripheral nerve sheath tumors showed ≥2+ staining, but staining did not correlate with grade. By contrast, only 7/97 (7%) synovial sarcomas were SOX10-positive. Only three synovial sarcomas showed ≥2+ staining but, importantly, two of these were intraneural synovial sarcoma. Therefore, SOX10 is a specific (93%), albeit not very sensitive (67%), diagnostic marker to support a diagnosis of malignant peripheral nerve sheath tumor over synovial sarcoma. Furthermore, the stain needs to be interpreted with caution in intraneural tumors in order to avoid a potential diagnostic pitfall. It remains to be determined whether SOX10-positive cells in intraneural synovial sarcoma represent entrapped Schwann cells, synovial sarcoma cells or both.

Pediatric primitive intraneural synovial sarcoma of L-5 nerve root

Primitive intraneural synovial sarcomas are rare in children. The authors report the case of a 7-year-old girl affected by intraneural synovial sarcoma of a lumbar nerve root, the first such lesion in this location described in a child. The lesion mimicked a schwannoma clinically and radiologically. There was long-lasting leg pain in a radicular distribution, and a well-demarcated intraneural tumor was seen on MRI. On this basis, the first resection was conservative. However, histological examination documented a classic biphasic synovial sarcoma, which was confirmed by immunohistochemistry. After radical resection and adjuvant treatment, complete disease control was achieved and verified at 5-year follow-up. This case strongly suggests that early diagnosis and a multidisciplinary approach to this unusual spinal lesion are essential to achieving a better prognosis.

Intraneural synovial sarcoma of the median nerve

Synovial sarcomas are soft-tissue malignancies with a poor prognosis and propensity for distant metastases. Although originally believed to arise from the synovium, these tumors have been found to occur anywhere in the body. We report a rare case of synovial sarcoma arising from the median nerve. To our knowledge, this is the twelfth reported case of intraneural synovial sarcoma, and only the fourth arising from the median nerve. Because the diagnosis may not be apparent until after pathological examination of the surgical specimen, synovial sarcoma should be kept in mind when dealing with what may seem like a benign nerve tumor.

Intraneural synovial sarcoma: two cases

We report two cases of intraneural synovial sarcoma. The first patient is a 46-year-old female who presented for several months with soft-tissue mass in the right infra-auricular region. The second patient is a 11-year-old girl who fell and then presented with pain in the area innervated by the right C7 spinal root and a nodule identified in the nerve root foramina. Both lesions were of small size and presented with features of synovial sarcoma. A biphasic variant was found in case 1 and a monophasic variant was present in case 2. Immunohistochemical studies were performed to confirm the diagnosis, excluding the main differential diagnoses, namely schwannoma and malignant peripheral nerve sheath tumor. Ultrastructural study was performed in case 2 allowing exclusion of other possible diagnoses. Molecular studies were performed on paraffin-embedded tissue in both cases and revealed the known characteristic t(X;18)(SYT-SSX) translocation.

Intraneural synovial sarcoma: two cases

We report two cases of intraneural synovial sarcoma. The first patient is a 46-year-old female who presented for several months with soft-tissue mass in the right infra-auricular region. The second patient is a 11-year-old girl who fell and then presented with pain in the area innervated by the right C7 spinal root and a nodule identified in the nerve root foramina. Both lesions were of small size and presented with features of synovial sarcoma. A biphasic variant was found in case 1 and a monophasic variant was present in case 2. Immunohistochemical studies were performed to confirm the diagnosis, excluding the main differential diagnoses, namely schwannoma and malignant peripheral nerve sheath tumor. Ultrastructural study was performed in case 2 allowing exclusion of other possible diagnoses. Molecular studies were performed on paraffin-embedded tissue in both cases and revealed the known characteristic t(X;18)(SYT-SSX) translocation.

INTRANEURAL SYNOVIAL SARCOMA OF THE MEDIAN NERVE

Intraneural synovial sarcomas are extremely rare in the main nerve trunks of the upper limb. We report on a 16-year-old youth who presented with a painless mass on the flexor aspect of the wrist with the clinical appearance of a ganglion. At operation there was a tumour of the median nerve that was shown on histology to be an intraneural synovial sarcoma.

Intraneural synovial sarcoma

This report describes and discusses the clinical, MRI, and pathologic findings in a case of synovial sarcoma arising within a peripheral nerve. Intraneural origin of synovial sarcoma is very unusual, and the MR imaging appearance of this condition has not been previously reported. MR imaging was valuable, as it showed the intraneural location and extent of the tumor, but it did not allow a specific histologic diagnosis.