An unusual case of a synovial sarcoma of the parotid gland in an elderly patient

Synovial sarcoma of the head & neck: A review of reported cases in the literature

Synovial sarcoma is a high-grade malignancy that seldom manifests in the head and neck. The purpose of this paper is to provide a comprehensive review of the existing literature on primary HNSS. This review study includes case reports, case series and retrospective cohort studies on primary HNSS published in the English language. All cases identified via PubMed were analyzed individually. Articles were included according to specified eligibility criteria. The total number of cases analyzed was 243 (91 case reports, 53 cases from 16 case series, and 99 cases from 8 retrospective cohort studies). The average age at the time of HNSS diagnosis was 33.5 years. The ratio of male-to-female was 1.64:1. The most frequently occurring histologic subtype was biphasic (59.2%). The most common location was the neck. Hoarseness was the most common presenting symptom. Almost all patients (98.3%) underwent surgical excision. 55.6% of patients received adjuvant radiotherapy. A smaller number of patients (30.7%) received adjuvant chemotherapy. 60.3% of patients were alive with no evidence of disease at follow-up while 28.0% of patients died of HNSS at follow-up. The average follow-up period was 52.0 months. Synovial sarcoma is a rare head and neck malignancy. Surgical excision with adjuvant radiation is the most frequently employed treatment modality. Regardless of treatment modality, the prognosis of the tumor is guarded.

Tumor size predicts prognosis of head and neck synovial cell sarcoma

Head and neck synoviosarcoma (HNSS) is uncommon. To the best of our knowledge, the specific clinicopathological characteristics, treatment outcome and prognostic factors of HNSS were uninvestigated at the time of writing, so a meta-analysis was performed. An online data collection was carried out using PubMed and Google Scholar. Studies that reported primary HNSS and the treatment, follow-up time and outcome were chosen for the present study. In total, 93 cases from 26 studies were included for analysis. The study sample consisted of 55 males and 38 females and the median age was 32.1 years (range, 4-76 years). The median follow-up period was 62.1 months (range, 1-373 months). The tumor size was correlated with local recurrence and metastasis of HNSS, as well as with mortality (P=0.001, P<0.0001 and P<0.0001, respectively). The three-year, five-year and 10-year survival rates were 82.1, 80.4 and 78.2% for treatment with surgery alone, and 88.5, 85.5 and 82% for treatment with surgery plus radiotherapy, respectively. A significant tumor size-dependent difference was found between the overall survival (OS) rates (P<0.0001), as tumors that were >5.0 cm in diameter were associated with a worse OS rate (hazard ratio, 6.460; 95% confidence interval, 206-18.917; P=0.001). The tumor size was found to be an independent adverse prognostic factor for the OS of HNSS patients. In conclusion, surgical excision is a mainstream treatment of HNSS and post-operative adjuvant radiotherapy improves the OS rate of HNSS patients.

Primary synovial sarcoma involving the submandibular gland

Synovial sarcoma represents 5.6%-10% of all soft-tissue sarcomas. Adolescents and young adults are most frequently affected, mainly in the deep soft tissue of the extremities. Only 10% of synovial sarcomas affect the head and neck region; most of these are biphasic. We describe a case of an 18-year-old man who complained of a mass in the right submandibular region that had been present for approximately 12 months. On surgical removal, microscopic analysis showed a tumor formed by sheets of malignant spindle cells involving the submandibular gland. Immunohistochemistry displayed positivity for AE1/AE3, CK18/8, epithelial membrane antigen, CD99, CD56, and TLE-1. Based on these immunohistochemical and histopathologic features, a diagnosis of monophasic synovial sarcoma was rendered. The patient was treated with adjuvant radiotherapy and after 1 year was free of disease. To the best of our knowledge, this is the first reported case of synovial sarcoma involving the submandibular gland.