Background
Retroperitoneal sarcomas (RPS) are rare tumors for which complete surgical resection remains the mainstay of treatment. We sought to determine the impact of hospital case volume on RPS outcomes.
Methods
We identified 6950 patients with primary RPS who underwent surgical resection from the National Cancer Data Base (1998–2011). Treating hospitals were classified by annual case volume; low volume hospitals (LVHs) and high volume hospitals (HVHs) were defined as ≤10 and >10 cases/year, respectively. Overall survival (OS) was compared using Kaplan-Meier curves. Cox proportional hazard models were created to compare risks.
Results
Of 1131 reporting hospitals, most (n=1127, 99.6%) were LVHs treating the majority of patients (n=6270; 90.2%). Patients treated at LVHs were more likely to have lower grade and smaller tumors, receive radiation therapy, and undergo incomplete gross (R2) resection. Patients treated at HVHs had lower 30-day readmission rates (1.8% vs 3.4%, p<0.001), 30-day (1.9% vs 3.1%, p=0.004) and 90-day mortality (3.2% vs 5.7%, p=0.007); longer median OS (76.2 vs 64.2 months, p<0.001) and higher 5-year OS (58% vs 52%, p<0.001). After controlling for age, gender, insurance status, tumor size, tumor grade, resection margin status, and radiation administration, treatment at a HVH was independently associated with a reduced risk of death (HR 0.77, 95% CI 0.65–0.91, p=0.003).
Conclusion
Primary RPS are rare tumors for which few surgeons and institutions have significant experience and expertise in their multidisciplinary management and surgical resection. Although additional studies are needed, patient outcomes may be impacted by treating facility case volume and experience.