Clinical outcomes of molecularly confirmed clear cell sarcoma from a single institution and in comparison with data from the Surveillance, Epidemiology, and End Results registry

BACKGROUND: The authors compared disease‐specific survival (DSS) in stage‐specific subgroups of patients with clear cell sarcoma, including those with lymph node metastases (N1M0) and those with distant metastases (N0M1). METHODS: Clinical data regarding soft tissue sarcoma patients were obtained from The University of Texas M. D. Anderson Cancer Center (MDACC) (1980‐2007) and the Surveillance, Epidemiology, and End Results (SEER) registry (1988‐2004). When possible, clear cell sarcoma diagnoses were confirmed using fluorescence in situ hybridization or reverse‐transcription polymerase chain reaction. Kaplan‐Meier estimates were used to calculate DSS, and Cox multivariate analysis was performed to identify prognostic factors. RESULTS: Fifty‐two patients at MDACC and 130 SEER patients were diagnosed with clear cell sarcoma. Five‐year DSS for the MDACC and SEER cohorts were 67% and 62%, respectively. Patients with N1M0 and N0M1 disease demonstrated significant differences in 5‐year DSS: 74% versus 14% at MDACC (P = .014) and 52% versus 0% in SEER (P = .014). After adjustment, the hazards ratio (HR) for dying was 2.79 for N1M0 disease (95% confidence interval [95% CI], 1.32‐5.91) and 11.37 (95% CI, 5.19‐24.91) for N0M1 disease compared with stage II disease (P < .001). Non‐Caucasian ethnicity (HR, 3.99; 95% CI, 2.27‐6.99 [P < .001]) and truncal tumor site (HR, 2.41; 95% CI, 1.15‐5.05 [P = .02]) were also found to be predictors of decreased DSS. CONCLUSIONS: The findings of the current study suggest that patients with N1M0 clear cell sarcoma have 5‐year DSS that is more similar to that of patients with stage III than stage IV soft tissue sarcoma. Cancer 2009. © 2009 American Cancer Society. The authors examined stage‐specific, disease‐specific survival in clear cell sarcoma patients identified from a prospectively maintained single‐institution database and from the Surveillance, Epidemiology, and End Results registry and found that patients with isolated regional lymph node metastases had better outcomes than patients with distant metastases.