Synovial Sarcoma of the Tongue: Report of a Case and Review of the Literature

Successful reconstruction using a buccal fat pad flap in misdiagnosed buccinators intramuscular synovial sarcoma: A case report

INTRODUCTION

Synovial sarcoma (SS) is a subtype of soft tissue sarcoma that primarily usually occurs in the lower extremities but rarely arises in the head and neck areas, including the oral cavity. Due to its variable presentation and similarity to benign masses in terms of age at onset, growth rate, and favorable outcomes, SS is often misdiagnosed as a benign tumor. However, it is a malignant tumor.

PATIENT CONCERNS

We report the case of intramuscular SS in the oral cavity. Initially, the lesion was clinically suspected as a benign mass but was ultimately confirmed as malignant SS.

DIAGNOSIS

Although histopathological examination is the first step in diagnosing SS, molecular testing to confirm the presence of SYT-SSX fusion can provide a definitive diagnosis when the histopathology is inconclusive. In this patient as well, the postoperative pathological report confirmed the diagnosis of biphasic SS, and molecular testing revealed positive SYT/SSX fusion.

THERAPEUTICS INTERVENTIONS

Following the recommendation of multidisciplinary care system, a wide excision was performed including the buccinators muscle, and reconstruction was performed using a buccal fat pad flap to prevent cheek depression.

OUTCOMES

On the final pathologic report, SS was removed margin-free, and there were no metastatic lymph nodes. No evidence of cheek dimpling was observed, and follow-up neck CT showed no significant changes in the lymph nodes. As a result of observation up to several months after surgery, there were no functional and aesthetic complications.

CONCLUSIONS

We report a successful case of intramuscular SS resection, initially misdiagnosed as a benign mass, using a buccal fat pad flap. We also highlight the importance of correctly diagnosing SS, especially in the craniofacial region where it can be mistaken for benign masses.

Primary Intraosseous Synovial Sarcoma in the Mandible

Synovial sarcoma (SS) is a rare malignant mesenchymal tumor that mainly occurs in body extremities, being uncommon in the head and neck region. In the present study, we described a case of primary intraosseous SS arising in the mandible of a 22-year-old young male. The patient reported a painful swelling on the left side of the mandible for the last 7 months. Imaging exams showed the presence of an expansive and multilocular radiolucent lesion, extending from the left condyle to the mandibular body. The clinic diagnostic hypotheses were ameloblastoma or malignant neoplasm. Histologically, the lesion was characterized by a proliferation of spindle cells exhibiting vesicular nuclei and evident nucleolus. Neoplastic cells were positive for AE1/AE3, cytokeratin 7, vimentin, CD-99, and TLE-1 and negative for CD-34, S-100, SMA, and HHF-35. A combination of clinical, histologic, and immunohistochemical characteristics supported the diagnosis of SS. The patient was referred for treatment, and preoperative exams did not reveal any other tumor foci in the body of the patient. The final diagnosis was of a primary intraosseous SS of the mandible.

Calcifying synovial sarcoma of the tongue with SS18 rearrangement: a rare variant in a rare location

Synovial sarcoma is a soft tissue malignancy harboring t(X;18) resulting in fusion of two genes SS8 (at 18q11) and SSX (1, 2 or 4 at Xp11) forming the gene fusion product SS18-SSX. It affects adults in their 3rd-4th decades, most frequently in the para-articular regions of the extremities. Less than 10% of the cases occur within the head and neck region and of these, 60% occur in the neck and only 10% occur in the oral cavity. We report a synovial sarcoma of the tongue in a 14-year-old female patient with unusual histology. The patient presented with a mass occupying most of the tongue with extension into the floor of mouth and the lingual gingiva of the anterior mandibular teeth. The tumor was composed of a highly cellular proliferation of spindle cells in a herringbone pattern with many small vessels but without glandular structures, and with extensive calcifications throughout the tumor. Tumor cells were positive for epithelial membrane antigen and transducin-like enhancer of split-1, and fluorescence in situ hybridization studies identified SS18 gene rearrangement. The patient was managed with two debulking procedures followed by chemoradiation and is currently alive with disease.

Synovial sarcoma of the tongue: report of a case and review of the literature

This report outlines the work-up and management of a 35-year-old man with a synovial sarcoma of the lateral border of the tongue. Synovial sarcoma of the tongue is an extremely rare tumour with variable morphological microscopic types and characters of immunohistochemical profile. There have only been 15 cases previously reported. This report aims to update the literature on this subject and explore the best treatment options.

Detection of Rare Variant of SS18-SSX1 Fusion Gene and Mutations of Important Cancer-Related Genes in Synovial Sarcoma of the Lip: Gene Analyses of a Case and Literature Review

Synovial sarcoma (SS) accounts for 5 to 10% of soft tissue sarcomas; however, intraoral SS is rare. Histopathologically, SS shows a biphasic pattern with epithelial and spindle cell components or a monophasic pattern with only spindle cells. The precise diagnosis of SS, especially at an unusual site, is often a challenge to pathologists and clinical oncologists, because the differential diagnosis of SS includes a broad range of tumors, such as soft tissue sarcomas and carcinomas. In the present case, the patient was a 50-year-old woman who presented with the chief complaint of swelling and a slowly enlarging mass of the lower lip in the mucolabial fold region. The mass was covered with intact mucosa and intraoral examination showed no malignant findings. The clinical diagnosis was a benign tumor and a probable salivary gland tumor. Macroscopically, the excised mass also indicated a benign tumor; however, histopathologic findings suggested the diagnosis of SS. For definitive diagnosis, genetic analyses were performed with conventional polymerase chain reaction and next-generation sequencing. As a result, a rare variant of the SS18-SSX1 fusion transcript, which could not be identified by routine procedures for genetic diagnosis, was detected. In addition, 8 missense mutations of cancer-related genes were confirmed. Detection of the fusion transcript is widely used in the diagnosis of SS; however, reported cases of transcript variants of each fusion gene type are limited. Reports of mutational analysis of cancer-related genes on SS also are rare. The accumulation of rare transcript variants and the cytogenetic characters of SS are suggested to be necessary for assuming a genetic diagnosis of SS.

Submental flap in intraoral reconstruction after pathologic resections: indications and limitations

INTRODUCTION

Submental flap is used to reconstruct intraoral and facial soft tissue defects. Submental flap is used for intraoral reconstruction in eighteen patients. Complications of this flap that includes local recurrence, remaining metastatic lymph node in the field of neck dissection, wound dehiscence at donor site and probability of transferring metastatic tissue are evaluated.

MATERIALS AND METHODS

This flap is used as an alternative to free tissue transfer, and this article presents 18 cases after pathologic lesion resections, such as verrocous carcinoma (2 patients), odontogenic myxoma (1 patient), oral squamous cell carcinoma (SCC) (10 patients), adenoid cystic carcinoma (2 patients), leukoplakia (2 patients) as well as osteosarcoma in one patient.

RESULTS

There was no case of local recurrence and remaining metastatic lymph node in the field of neck dissection. A case of metastatic lymph node involvement in posterior triangle of the neck, 2 years after surgery was occurred. One case of metastatic tissue transfer and a case of wound dehiscence in submental region are reported.

CONCLUSION

Submental flap is an useful aid for reconstruction of oral cavity mucosal defects. Its use in oral SCC reconstruction should be done in carefully selected cases.

Synovial Sarcoma of the Tongue Confirmed by Molecular Detection of the SYT-SSX2 Fusion Gene Transcript

Involvement of the tongue by a synovial sarcoma (SS) is an extremely rare event; there have only been 13 cases previously reported. The authors present herein a case of monophasic SS arising in the tongue in a 32-year-old woman. The neoplasm expressed cytokeratins AE1-3, OSCAR, and EMA as well as Bcl-2 and TLE1. Molecular analysis indicated that the patient tested positive for the SYT/SS2 fusion transcript.

Diagnosis and treatment of primary synovial cell sarcoma that occurred in the left mandible body: a case report and literature review

OBJECTIVE

The authors describe a case of synovial sarcoma in the left mandible body.

STUDY DESIGN

The primary tumor was investigated morphologically and immunohistochemically. The patient was treated with madibulectomy and lymph node dissection, which was followed by an immediate reconstruction of the left mandible with a revascularized osteomyocutaneous fibula free flap.

RESULTS

The primary tumor was described as gingival sarcoma. The initial preoperative biopsy showed positive staining for cytokeratin, vimentin, smooth muscle actin, and desmin by immunohistochemistry. The definitive diagnosis of monophasic synovial sarcoma was established following postoperative excision biopsy. Antigens of S-100 and CD99 displayed positive staining but epithelial membrane antigen, Bcl-2, and CD34 were negative. Also, no metastasis or other bone swelling was observed by radionuclide survey suggesting the left mandible was the primary lesion of occurrence.

CONCLUSIONS

Synovial sarcoma is an uncommon soft tissue malignant neoplasm. This is the sixth case of primary synovial sarcoma occurring in the jaw.