Predisposing factors for metastatic disease at initial diagnosis of synovial sarcoma: A big data analysis (n = 2162).

BACKGROUND: Synovial sarcoma (SS) is an aggressive soft tissue malignancy of mesenchymal origin. We reexamined potential predisposing factors predictive of metastatic disease at initial diagnosis of SS using Big Data Analysis. METHODS: The U.S. Surveillance, Epidemiology, and End Results (SEER) Program database was queried to identify patients diagnosed with SS from 2000 to 2018. Cases were stratified at presentation as metastatic or localized disease. Patient demographics and tumor characteristics were analyzed using univariate and multivariable logistic regression models to identify factors independently associated with metastatic presentation including age greater than 50 years, tumor in the pelvic area, and relative tumor size. RESULTS: A total of 2162 cases of histologically confirmed SS were identified, of which 382 (17.7%) presented with metastatic disease at diagnosis. Based on an unadjusted logistic regression analysis, patients had the highest odds of metastatic disease at initial diagnosis if they were over the age of 50 (odds ratio [OR] = 2.77; 95% confidence interval [CI], 2.00-3.80), had tumors located in the pelvic region (OR = 3.28; 95% CI, 2.13-5.06), or had a tumor size greater than 10 cm (OR = 8.98; 95% CI, 5.87-13.74). These factors remained significant when combined in a multivariable model controlling for age, sex, race, tumor location, histology, size, and socioeconomic factors. CONCLUSION: SS patients who are over the age of 50 years, have tumors in the pelvic region, or have tumors larger than 10 cm in size are more likely to present with metastatic disease at initial diagnosis.