Chondrosarcoma of the Flat Bones: Differential Survival Between High-Grade Lesions of the Pelvis and Scapula.

Abstract

Background: Flat bone chondrosarcomas have worse outcomes than extremity tumors, but there is no data directly comparing the different flat bones. The aim of this study was to examine differences in recurrence and survival between pelvic and scapular chondrosarcoma.

Methods: One hundred and sixty-nine (42 scapula, 127 pelvic) patients with chondrosarcoma who underwent surgical resection were reviewed. High-grade tumors were defined as lesions that were Grade 3 or dedifferentiated on surgical pathology.

Results: Patients with low-intermediate grade lesions of the scapula were more likely to have positive margins during definitive surgical management (14% vs. 3%, OR 5, 95% CI [1.15, 22.6], p = 0.02), however, this did not translate to differences in recurrence or survival (p > 0.05). The presence of an associated soft tissue mass in low-intermediate grade lesions was not associated with increased recurrence. Among high-grade tumors, patients with scapular lesions had worse DSS (HR 2.99, 95% CI [1.05, 8.51], p = 0.04). One- and 2-year DSS for high-grade pelvic tumors was 75% and 57%, respectively, and 50% and 33% for scapular tumors.

Conclusion: Survival for high-grade chondrosarcoma of the flat bones is poor, particularly for those of the scapula. Despite a higher rate of positive margins for low-intermediate grade lesions of the scapula, there was no significant difference in survival compared to low-intermediate grade lesions of the pelvis. Additional studies with larger sample sizes are needed to further elucidate differences between these locations.