Periosteal margin in soft-tissue sarcoma

BACKGROUND: Soft-tissue sarcomas frequently rest in contact with bone. The purpose of the study was to evaluate the risk of local recurrence for sarcomas adjacent to bone and to determine whether the periosteum provides an adequate margin of resection. METHODS: Fifty patients with soft-tissue sarcomas abutting bone were treated at a single institution between 1990 and 2004. All patients had high-grade, T2 (>5 cm), nonmetastatic disease in the lower extremity. Bone contact was verified by preoperative magnetic resonance imaging (MRI) and/or computed tomography (CT) scans. Forty-three of 50 patients received preoperative radiation with a mean dose of 50 Gy. In 11 cases a composite resection of bone and soft tissue was performed. In 39 cases the excision involved only soft tissue. RESULTS: True bone invasion was verified by histopathologic examination in 3 of 50 cases (6%). Local recurrence in the soft tissues developed in 8 of 50 (16%) patients. In no case did the recurrence involve destruction of cortical bone or erosion into bone. The recurrent tumor resided against the region of previous bone contact in 1 of 8 cases. There was no statistically significant difference in local recurrence between patients who had composite bone resection and patients who had soft-tissue resection only (P = .87). CONCLUSIONS: Relatively few sarcomas are able to penetrate cortical bone. Composite bone and soft-tissue resections are indicated primarily for frank bone invasion. In the absence of this, the periosteum is an adequate surgical margin for sarcomas treated with wide excision and radiation.