Primary anatomical site as a prognostic factor for pleomorphic liposarcoma

Pleomorphic liposarcomas (PLS) is an aggressive, high-grade subtype of soft tissue sarcoma representing < 15% of liposarcomas. It most commonly arises in the retroperitoneum and proximal upper extremities. Current prognostic factors are centered around staging, which accounts for the grade, size, and location of the tumor in relation to the superficial fascia.

750 patients diagnosed with pleomorphic liposarcoma from the National Cancer Database were analyzed. Kaplan-Meier survival tables, log-rank tests, and Cox proportional hazards analysis were utilized to compare survival between groups within variables.

The most common primary anatomical site was the lower limb/hip. The head/neck primary anatomical site demonstrated the highest 10-year overall survival probability, while the retroperitoneum/abdomen had the lowest (50% and 18.4%). Compared to the thorax/lung site, the following sites demonstrated a decreased risk of death: lower limb/hip (HR = 0.54; 95% CI: 0.35-0.82, p = 0.004), pelvis (HR = 0.49; 95% CI: 0.28-0.84, p = 0.010), and the retroperitoneum/abdomen (HR = 0.54; 95% CI: 0.33-0.89, p = 0.015). Both adjuvant radiation (HR = 0.64; 95% CI: 0.48-0.85, p = 0.002) and neoadjuvant radiation (HR = 0.70; 95% CI: 0.49-1.00, p = 0.049) provided a survival benefit to patients. There was an increased risk of death for every 10-year increment in age (HR = 1.31; 95% CI: 1.12-1.45, p < 0.001).

Statistically significant prognostic factors for PLS include primary anatomical site, age, Charlson-Deyo Comorbidity Index Scores and the use of neoadjuvant and adjuvant radiation.