Clinical profile and outcome of pediatric synovial sarcoma - Eleven-year experience from a tertiary cancer center in LMIC.

Background: Synovial sarcoma (SS) is the most common non-rhabdomyosarcoma soft tissue sarcoma in children. Data regarding the outcome in children from developing countries are scarce. We analyzed the clinical characteristics and outcome of pediatric SS.

Materials and methods: Children ≤14 years of age, diagnosed to have SS between January 1, 2007 and December 31, 2017 at a tertiary cancer center in India, were retrospectively analyzed. Details regarding clinical presentation and treatment were recorded, and the outcome was analyzed using Kaplan-Meier survival analysis.

Results: Fourteen children were diagnosed with SS. The median age was 132 months (range 54-168 months), and the male:female ratio was 1.8:1. Group I, II, III, and IV disease was seen in four (28.6%), six (42.9%), three (21.4%), and one (7.1%) child, respectively. Extremity was the most common site of primary (n = 13, 92.8% children). Tumor size was ≤5 cm in nine (64.3%) children. The treatment modalities were surgery only (n = 2, 14.3%), surgery and radiation (n = 1, 7.1%), surgery and chemotherapy (n = 5, 35.7%), and surgery, radiation, and chemotherapy (n = 6, 42.9%). At a median follow-up of 62.5 months (range 18-125 months), the 4-year event-free survival (EFS) and the overall survival were 77.7% and 85.7%, respectively. The 4-year EFS for children with smaller tumors (≤5 cm) was 77.8%, compared to 60% for children with larger tumors. The 4-year EFS for male was 53.3%, compared to 100% for female patients.

Conclusion: Our study demonstrates that good survival can be achieved in children with SS in low- and middle-income countries (LMICs) by appropriate utilization of the available resources judiciously. Smaller tumor size and female gender were associated with a better outcome.