Risk factors and oncological outcomes of pulmonary metastasis in patients with giant cell tumor of bone.

ABSTRACT

BACKGROUND: Giant cell tumor (GCT) of bone has a rare potential for metastatic spread. This study aimed at evaluating the incidence of chest metastases in GCT and their oncological outcome and identifying possible risk factors. METHODS: Medical records of 466 (313 de novo and 153 recurrent) patients with primary GCT of bone were retrospectively reviewed. Fifteen (3.2%) patients developed chest metastasis. Time from diagnosis of the primary bone lesion to the diagnosis of metastasis, treatment modalities of metastasis, and the course of treatment were revised. The functional outcome was evaluated using the Musculoskeletal Tumor Society (MSTS) scoring system, and postoperative complications were recorded. RESULTS: This study included 7 males and 8 females with a mean age of 27.3 ± 7.9 years. The most common site of the primary tumor was the distal femur. All fifteen patients were recurrent cases. The mean follow-up period was 67.7 ± 33.2 months. Chest metastasis was diagnosed after a mean time of 28.1 ± 28.9 months from the initial diagnosis of the bone lesion. One patient died of disease (DOD) 18 months after the surgical intervention. The incidence of chest metastasis in recurrent cases was 9.8%, while de novo cases did not develop chest metastasis, P < 0.001. Previous curettage was associated with a higher incidence of chest metastasis (14.6%) compared to previous resection (4.2%), P = 0.03. CONCLUSIONS: Chest metastasis following GCT of bone is rare. Risk factors include recurrent cases, especially following previous curettage. Patients have a good prognosis and a low mortality rate. LEVEL OF EVIDENCE Level IV, retrospective.