Synovial Sarcoma of the Hand and Foot: An Institutional Review

Synovial sarcomas (SS) arising in distal extremities are rare and have been studied using mostly case reports and small series. We aimed to evaluate clinical presentation and survival outcomes for patients with hand or foot SS.

We conducted a retrospective review of 84 patients diagnosed with primary hand (n=20) and foot (n=64) SS between 1979 and 2019. Progression-free survival (PFS), overall survival (OS), local recurrence-free survival and metastasis-free survival were estimated using the Kaplan-Meier method and log-rank test. Cox-proportional hazards regression was used to estimate the hazard ratios.

Of 84 patients, 63 (75%) presented with localized disease with 36 years median age at diagnosis (range: 4 to 76) and 21 (25%) with metastasis with 30 years median age at diagnosis (range: 15 to 64). Among patients presenting with localized disease, (1) 5 years-PFS, OS, local recurrence-free survival, and metastasis-free survival rates were 82%, 88%, 100%, and 86%, respectively. (2) Tumor size <3.0 cm corresponded to 95% 5 years-PFS (vs. 84% for 3.0 to 4.9 cm, 53% for ≥5.0 cm; P=0.007) and 100% 5 years-OS (vs. 77% for ≥3.0 cm; P=0.04). (3) Patients with ≥5.0 cm (vs. <3.0 cm) tumor size had 7.99 (95% confidence interval: 1.68, 37.91) times higher hazard of progression. Remarkably, patients presenting with metastasis had 50% 5 years-OS rate. Also, younger age (15 to 39 vs. 40 y and above) predicted better OS among patients presenting with localized disease (P=0.04) and with metastasis (P=0.03).

Survival outcomes are favorable for younger patients with <3.0 cm hand or foot SS. Local control is excellent, but we observed larger tumor size to be associated with poorer outcomes. Therefore, we recommend consideration of systemic therapy for patients with ≥3.0 cm hand or foot SS.