Clear Cell Sarcoma Incidence and Survival: A Surveillance, Epidemiology, and End Results (SEER) Database Analysis

Background Clear cell sarcoma (CCS) is a rare soft tissue cancer that predominantly affects young to middle-aged adults. Current literature lacks recent and accurate estimates of patient outcomes due to the disease's low incidence and the small sample sizes in existing studies. This study aims to examine the incidence and survival of patients with CCS. Methods Patients from the Surveillance, Epidemiology, and End Results (SEER) database diagnosed with CCS between 2000 and 2019 were selected. Additional variables collected included age, sex, race, stage, metastases, tumor size, treatment status for surgery, radiation, and chemotherapy, median household income, and population size. Descriptive statistics, population-based incidence, chi-square tests, and Cox regression analyses were performed. Results A total of 268 patients were included. The population-adjusted incidence ranged from 0.012/100,000 to 0.027/100,000. The total percent change over the study period was 16.751%, and the annual percent change was 0.561%. The survival rates at one, three, and five years were 78.4%, 62.0%, and 57.1%, respectively. Cox regression results showed that Black patients (p = 0.007), tumor size greater than 4.0 cm (p = 0.033), and the presence of metastases (p = 0.040) were all associated with shorter survival. Significance The findings showed that CCS incidence has remained unchanged in recent years and that prognosis is poor. Black patients were found to have shorter survival durations. Contrary to prior findings, staging and tumor size were only significantly associated with survival in univariate analyses. Limitations include a small sample size and the constraints of variables available in the SEER database. Nonetheless, future research will benefit from assessing whether race is an independent risk factor for CCS survival and from exploring ways to improve prognosis.