Synovial Sarcoma

Introduction Sarcomas are representing in less than 1% of adult malignancies and approximately 10% of pediatric cancers [1]. Synovial sarcoma (SS) is often affecting limbs and joints and is usually associated with a specific genetic translocation, t(X:18)(p11.2;q11.2) [2]. However, in this case SS has formed on a newborn’s forehead and specific t(X:18)(p11.2;q11.2) translocation was not found. For this reason, clinical knowledge of this condition is limited. Case Presentation A full-term newborn presented with a 4.5 x 4.5 cm mass on the right forehead, initially resembling an encephalocele. The mass was firm, mobile, and had altered skin overlying it. Neurosonography revealed a non-homogeneous, echogenic mass, which was not connected to the skull. Magnetic resonance imaging showed a well-defined soft tissue tumor, not involving the bone. Consultation with genetics, pediatrics, and oncology was initiated. The tumor was surgically removed and histologically tested. Histological analysis confirmed SS (most probably monophasic type): spindle-shaped cells with oval nucleus, multiple mitoses, positive CD99, TLE-1 marks. No spreading of disease was found. Genetic testing did not reveal SS18-SSX translocation. 3 months after tumor resection surgery, local recurrence of tumorous growth was clinically and radiographically confirmed. Patient has a treatment planed with 6 rounds of chemotherapy with Vincristine and Dactinomycine. Discussion Synovial sarcoma often affects the limbs, particularly around large joints [3]. Although the genetic test did not confirm the common SS18-SSX translocation, the histological features were consistent with SS. This case highlights the challenges in diagnosing SS in neonates, as well as the importance of considering a multidisciplinary approach for both diagnosis and treatment. The standard treatment involves surgery, with chemotherapy considered for highrisk cases [4]. Conclusions Synovial sarcoma, though rare, should be considered in cases of soft tissue tumors, even in neonates. Early surgical resection is crucial, but the risk of recurrence and metastasis requires ongoing monitoring and adjuvant treatment [4]. Further research is necessary to understand the genetic variations in SS and their impact on prognosis and treatment response.