Synovial Sarcoma of the Neck

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.

Synovial sarcoma of the posterior neck : a case report and review of literature

We recently experienced a case of synovial sarcoma in the posterior neck, which involved adjacent bony structures. Synovial sarcoma is rare, malignant soft tissue tumor that occur predominantly in the lower extremities. Wide surgical excision with involved tissue is the treatment of first choice, because most synovial sarcomas reveal aggressive features. We removed the tumor with involved bony structures and patient was given postoperative radiation therapy. Despite these treatment options, the patient died 1 year after surgery. We report this case with a review of the literature.

Activation of the non-canonical Dvl-Rac1-JNK pathway by Frizzled homologue 10 in human synovial sarcoma

We previously reported that Frizzled homologue 10 (FZD10), a member of the Wnt signal receptor family, was highly and specifically upregulated in synovial sarcoma and played critical roles in its cell survival and growth. We here report a possible molecular mechanism of the FZD10 signaling in synovial sarcoma cells. We found a significant enhancement of phosphorylation of the Dishevelled (Dvl)2/Dvl3 complex as well as activation of the Rac1-JNK cascade in synovial sarcoma cells in which FZD10 was overexpressed. Activation of the FZD10-Dvls-Rac1 pathway induced lamellipodia formation and enhanced anchorage-independent cell growth cells. FZD10 overexpression also caused the destruction of the actin cytoskeleton structure, probably through the downregulation of the RhoA activity. Our results have strongly implied that FZD10 transactivation causes the activation of the non-canonical Dvl-Rac1-JNK pathway and plays critical roles in the development/progression of synovial sarcomas.

Molecular target therapy for synovial sarcoma

Although the specific chromosomal translocation and fusion gene SYT-SSX in synovial sarcoma (SS) has been identified, the molecular mechanism of its tumorigenesis is largely unknown. Recent gene-expression profiles of soft-tissue tumors using cDNA microarray demonstrated that SS has the distinct gene-expression pattern from other sarcomas and has a similar pattern to that of malignant peripheral nerve sheath tumors, indicating that the origin of SS is likely to be the neural crest cells. Through this analysis, several genes were found to be specifically upregulated in SS and considered to play an important role in the proliferation of SS cells. Among them, Frizzled homolog 10 was identified as a good candidate molecule for the development of novel therapies to treat SS patients.