TWO-STAGE RECONSTRUCTION OF A FEMORAL METASTASIS FROM PAPILLARY THYROID CARCINOMA USING A CEMENT SPACER AND STRUCTURAL FIBULAR AUTOGRAFT: A CASE REPORT

Abstract

Introduction and importance: Femoral metastases from differentiated thyroid carcinoma may occur in patients with prolonged survival and create a dual oncological and mechanical challenge. Durable reconstruction after wide resection is therefore particularly relevant in selected patients. Case presentation: A 54-year-old woman with differentiated thyroid carcinoma and a history of papillary thyroid carcinoma metastasis presented with progressive mechanical pain of the left thigh. Radiographs showed an approximately 7-cm osteolytic lesion at the junction of the middle and distal thirds of the femur without pathological fracture. PET imaging demonstrated a hypermetabolic femoral lesion. Wide en bloc resection was performed with macroscopically safe 3-cm proximal and distal margins. The first-stage reconstruction used an intramedullary nail and a polymethylmethacrylate cement spacer. Histopathology confirmed a femoral metastasis from papillary thyroid carcinoma with clear resection margins. In a second stage, the spacer was removed and biological reconstruction was performed using an ipsilateral structural fibular autograft stabilized with a plate. Clinical discussion: In patients with an expected prolonged survival, biological reconstruction may provide a durable alternative to purely prosthetic reconstruction. A staged strategy can maintain segmental length and temporary stability before definitive graft-based reconstruction. Conclusion: Two-stage reconstruction using a cement spacer followed by structural fibular autografting achieved graft integration, radiographic union and satisfactory functional recovery in this patient, with no local recurrence or mechanical or infectious complication at the latest follow-up.