A case of primary synovial sarcoma of the retropharyngeal space

Abstract

Background：Most malignant tumors that occur in the pharynx are epithelial in origin, as typified by squamous cell carcinoma, and malignant tumors of submucosal origin are rarely observed. We herein report a case of synovial sarcoma originating in the submucosal region of the hypopharynx. Case：A 50-year-old man consulted a physician complaining of pharyngeal pain. Imaging tests suggested a retropharyngeal space abscess. Transoral incision and drainage were performed, during which a solid lesion was observed in the retropharyngeal space, and a tissue biopsy was performed. A definitive diagnosis of synovial sarcoma was made, and the patient was referred to our department. Because the tumor was highly malignant, we performed laryngopharyngeal and cervical esophagectomy to ensure a sufficient safety margin. He developed pulmonary metastasis in the early postoperative period, and despite multiple resections of the pulmonary lesions and continued chemotherapy, the disease became uncontrollable. He ultimately died of primary disease approximately five years after the initial surgery. Conclusion: Malignant tumors that develop under the pharyngeal mucosa are difficult to detect. This disease should always be considered as a differential diagnosis in cases of pharynx-related chief complaints, and an early imaging diagnosis should be actively considered.