1.P.09 ONCOLOGICAL OUTCOME FOLLOWING LIMB SALVAGE SURGERY DONE FOR HIGH GRADE OSTEOSARCOMA PATIENTS WHO WERE INITIALLY TREATED INADEQUATELY BY CURETTAGE OR DRAINAGE

Abstract

Patients with high-grade osteosarcoma who have been previously misdiagnosed as benign lesions or infection and accordingly been treated by curettage, internal fixation or drainage present a challenge in deciding the most appropriate treatment plan. Since one of the contraindications of limb salvage is the inability to achieve a wide surgical margin, there has been a tendency to treat these patients by amputation. Due to contamination by previous surgeries, limb salvage surgery was thought to be associated with a higher risk of local recurrence.

The aim of this study was to evaluate the oncologic outcome following limb salvage surgery done for high-grade osteosarcoma patients who were initially treated inadequately by curettage, internal fixation or drainage.

The study included 24 patients (14 males and 10 females) with an average age of 19 years (range 7 to 39 years). All the patients had high-grade osteosarcoma of the extremities. Seven were located in proximal tibia, six distal femur, four proximal humerus, three proximal femur, two distal tibia, one distal radius and one fibula. 14 patients were previously diagnosed as benign lesions and treated by curettage. 5 patients were diagnosed as regular fracture and internally fixed. 5 patients were diagnosed as osteomyelitis and treated by drainage. The patients were staged then treated by neoadjuvant chemotherapy and limb salvage surgery. The average time between the initial procedure and the limb salvage procedure was 7 months (range 3 to 36 months). A wide resection margin was achieved in all patients.

The average follow up period was 40 months (range 18 to 110 months). Local recurrence occurred in three patients (12.5%). Three patients developed chest metastases and one patient developed bone metastases.

We conclude that patients who had an inadequate surgical procedure prior to the diagnosis of a high-grade osteosarcoma could still be treated by neoadjuvant chemotherapy and limb salvage surgery without a significant increased risk of local recurrence and chest metastases.