A Population-based Analysis of Lymph Node Metastasis in Extremity Soft Tissue Sarcoma: An Update

Area of Science:

• Oncology
• Surgical Pathology
• Cancer Research

Background:

• Soft tissue sarcomas (STSs) are rare mesenchymal tumors.
• Lymph node metastasis is an uncommon but significant event in STSs.
• Regional lymph node metastasis (RLNM) in extremity STS requires further investigation.

Purpose of the Study:

• To evaluate the incidence and prognostic impact of RLNM in extremity STS.
• To identify prognostic factors associated with disease-specific survival (DSS) in extremity STS.
• To inform potential modifications to STS staging systems.

Main Methods:

• Retrospective review of the Surveillance, Epidemiology, and End Results (SEER) database (1975-2016).
• Analysis of a national cohort of patients with extremity STS.
• Application of Cox proportional hazards models to determine prognostic factors for DSS.

Main Results:

• RLNM was identified in 3.7% of extremity STS cases.
• Specific STS subtypes showed higher rates of RLNM, including rhabdomyosarcoma (26.7%) and epithelioid sarcoma (14.5%).
• The 5-year DSS was significantly lower for patients with RLNM (26%) compared to those without (69%).
• Advanced age, higher tumor grade, larger tumor size, and distant metastasis were also independent prognostic factors.

Conclusions:

• RLNM in extremity STS carries a poor prognosis, with a 5-year DSS of 26%.
• These findings support the inclusion of nodal status in STS staging.
• The study contributes to understanding RLNM rates and their clinical significance in STS.