Nodal Involvement and Survival Analysis in Synovial, Clear Cell, Angio, Rhabdo, and Epithelioid(SCARE) Sarcoma

Abstract

Synovial, Clear cell, Angiosarcoma, adult Rhabdomyosarcoma and Epithelioid sarcoma is often referred to by the mnemonic SCARE as soft tissue sarcoma subtypes with higher risk of lymph node involvement(LNI). This study is to identify the incidence of LNI, prognosis and predictors of LNI, treatment and patterns of failure. We identified 829 patients with the diagnosis of the above 5 histologies who were treated in our institution and retrospectively reviewed 343 patients who were diagnosed from 2000 to 2017. Statistical significance was assessed with Chi-square and Wald tests. Kaplan-Meier analysis was used to analyze survival outcomes. Primary SCARE sarcoma sites include head and neck(71, 21%), upper extremity(57, 17%), lower extremity(90, 26%), thorax, abdomen and pelvis(47, 14%), trunk and retroperitoneum(44, 13%), GU, GYN and other(34, 10%). 152 present with Stage 2 and 109 with Stage 3 disease (AJCC7). Primary tumor size was =< 5 cm in 123, 5-10 cm in 77 and >10 cm in 57. LNI was found in 54(16%) patients, of whom 48 were positive at diagnosis and 6 were found during follow up. LNI rates differed significantly (table 1). Tumor size(p=0.05), histology(p<0.001), metastasis(p<0.001) were found as predictors of LNI. 282(82%) patients underwent resection with R0 in 177 patients. Sentinel lymph node biopsy was performed in a limited number of patients. 171(50%) patients received chemotherapy. 247(72%) patients received radiation therapy. Median follow up is 26.5 months. 5-year overall survival(OS) in SCARE histology is 72.7, 41.3, 34.5, 30.8, 45.4% respectively. Synovial sarcoma(SS) has better survival compared to others(p<0.001). LNI was associated with worse OS (p=0.001) and progression free survival(PFS, p=0.001). Multivariate analysis identified LNI(HR=1.89, p=0.005), large tumor size(HR=1.05 per cm, p=0.003), metastasis(HR=3.31, p<0.001) as significant factors affecting OS. For PFS, LNI(HR=1.75, p=0.02), and metastasis(HR=2.13, p=0.002) are independent negative prognostic factors. LNI is significantly higher in clear cell, angiosarcoma, rhabdomyosarcoma and epithelioid sarcoma than SS, is predicted by larger tumor size, and has poorer prognosis.Abstract 153; Tablesynovialclear cellangiosarcomarhabdomyosarcomaepithelioidTotal 34312518787349LNI(p=0.0015)6%28%15%21%29%metastasis(NS)10%3%23%27%24% Open table in a new tab