Disease Characteristics, Patterns of Care and Survival Outcomes in Patients with Synovial Cell Sarcoma of the Head and Neck (HNSCS)

Abstract

<h3>Purpose/Objective(s)</h3> HNSCS is a rare diagnosis with an overall poor prognosis. Due to its rarity, our understanding of HNSCS and its optimal management is mainly derived from retrospective and single-institution studies. We aimed to evaluate the disease characteristics, patterns of care, and survival outcomes in patients with HNSCS. <h3>Materials/Methods</h3> Using the National Cancer Database (NCDB), we identified patients with HNSCS diagnosed between 2004 and 2018. Kaplan-Meier analysis was used to evaluate the significance of treatment options and disease characteristics on overall survival (OS). Univariate (UVA) and multivariate Cox proportional hazard models (MVA) were used to identify prognostic factors associated with OS. <h3>Results</h3> Our study cohort consisted of 414 patients with a mean age of 38.1 years (range 1 to 82 years). 61.1% of patients were male and 38.9% were female. 40.1% of cases were coded as spindle cell histology, and 18.7% were coded as biphasic; in 40.9% of cases, the tumor was classified as synovial sarcoma, NOS. Regarding tumor size, 9.7% (n=40) were ≤2 cm, 27.8% (n=115) were >2 cm and ≤4 cm, and 49.3% (n=204) were >4 cm. 354 patients (85.5%) were treated with surgery (among whom n=126 had laser/excisional biopsy). Of the patients who underwent surgery, 203 patients achieved negative margins and 109 patients had positive margins. 56.3% of patients received radiation therapy (RT) to the head and neck while 37.9% did not. Of the patients who received head and neck RT, 188 received adjuvant RT, 23 received neoadjuvant RT, and 17 received RT alone. The 5-year OS rate for the entire cohort was 75.4%. The 5-year OS for no surgery, laser/excisional biopsy, and surgery were 55.5%, 84.3%, and 74.9%, respectively (p<0.001). On MVA, factors associated with worse OS included no surgery or positive margins, tumor size >4 cm, node-positive disease, CDCC score ≥1, male sex, and older age were significantly associated with worse OS. <h3>Conclusion</h3> HNSCS is a rare and aggressive oncological entity with limited information regarding the optimal management and disease characterization. In a national database analysis of patients with HNSCS, the largest cohort of patients with this rare condition reported to date, we report a 5-year OS of 75.4%. Proper management should include surgery with negative resection margins when possible.