Primary Mediastinal Synovial Sarcoma Presenting as Superior Vena Cava Syndrome: A Rare Case Report and Review of the Literature

Abstract

Primary mediastinal sarcomas are aggressive tumors with a very rare incidence. This report describes the case of a 35-year-old male patient who presented with acute symptoms of dyspnoea, facial puffiness, voice-hoarseness, and engorged neck veins. With the clinical picture consistent with the superior vena cava (SVC) syndrome, the patient was investigated with computed tomography of the chest. This revealed a large soft tissue density mass lesion compressing the SVC along with other critical superior mediastinal structures. Histopathological evaluation of the mass revealed features consistent with a soft tissue sarcoma and positive staining was observed for vimentin and S-100. Cytogenetic analysis by fluorescent in situ hybridisation (FISH) demonstrated the t(X:18) translocation. Thus diagnosis was established as primary mediastinal synovial sarcoma. Patient was treated with three cycles of neoadjuvant chemotherapy, to which there was a partial response as per the RECIST criteria. Surgical excision of the mediastinal mass was performed, and further postoperative treatment with adjuvant chemoradiotherapy was provided. Patient currently is free of disease. This is to the best of our knowledge the first report in the world literature of a successfully treated case of “primary mediastinal sarcomas presenting as SVC syndrome.” Patient is under regular surveillance at our clinic and remains free of recurrence one year after treatment completion.

A Primary Mediastinal Monophasic Spindle-Cell Synovial Sarcoma with Superior Venacaval Obstruction

“…The common sites of occurrence are in the lower extremities and near the joints [ 5 ]. They occur at other sites of the body, but only a few cases reported the mediastinum as a site of origin [ 2 , 6 ]. However, in our case, the age of presentation was the fifth decade, and the site of origin was the mediastinum, which was unusual.…”

“…The classically recognized variant is the biphasic type, which consists of a mixture of epithelial and bland-looking spindle-shaped cells. On the other hand, the monophasic type exhibits either spindle cells or epithelial components only [ 5 , 6 ].…”

Management of locally advanced primary mediastinal synovial sarcoma

“…Independent case reports of PMSS have been reported with treatment using different modalities. [ 5 6 7 ] Patients with borderline resectable or unresectable localized disease can be treated with neoadjuvant chemotherapy (NACT) to downstage the tumor and achieve an R0-resection. [ 5 6 ] SS is sensitive to chemotherapy with reported response rates of 30–55%.…”

“…[ 5 6 7 ] Patients with borderline resectable or unresectable localized disease can be treated with neoadjuvant chemotherapy (NACT) to downstage the tumor and achieve an R0-resection. [ 5 6 ] SS is sensitive to chemotherapy with reported response rates of 30–55%. Ifosfamide-based regimens are commonly used[ 8 ] with or without doxorubicin and appear to be associated with the highest reported objective response rate.…”

A case of marantic endocarditis with systemic emboli in a patient with metastatic soft tissue sarcoma

“…Sarcomas are mesenchymal neoplasms arising either from bone or soft tissue. [1][2][3] Although this disease group tends to be uncommon in the spectrum of adult medicine, malignant sarcomas represent the most common type of solid tumor in pediatric oncology patients and are increasingly important to the medical community. [3] Soft tissue sarcomas are further subclassified as deriving from muscle, tendon, fat, fibrous connective tissue, synovial tissue, blood vessels or nerve.…”