Analysis of Lung Metastases in Patients with Primary Extremity Sarcoma

PURPOSE To investigate the incidence, radiographic findings, and the time course for the appearence of lung metastases from primary extremity sarcoma. PATIENTS AND METHODS Four-hundred patients with extremity sarcoma were evaluated retrospectively for lung metastases. Multiple clinical factors were analyzed for possible influence on the metastases-free interval and subsequent metastases development. Radiographic findings of metastases were also reviewed. RESULTS Ninety of 400 patients (23%) developed lung metastases. Median time from presentation to detection of metastasis was 8.0 +/- 1.1 months (95% CI: 6.02-9.98). More than 75% of patients developed metastases within 1 year after presentation of the primary sarcoma. As disease grade increased, the metastases-free intervals shortened significantly. Histologically, synoviosarcoma and osteogenic sarcoma were more often associated with the development of lung metastases. In this subgroup, 54 patients (60%), the presence of solitary (11) or multiple (43) nodular metastases was the only radiological finding. In 36 of 90 patients (40%), parenchymal mass, pleural effusion, hilar lymphadenopathy and pneumothorax were found. CONCLUSIONS Twenty-three percent of patients in our study developed lung metastases. As the grade of the disease increased, metastases-free intervals are shortened. Although it has been reported that lung metastases in patients with extremity sarcomas may present as solitary or multiple nodules in earlier trials with radiographic screening methods, the current review of 400 patients found that a substantial number of patients may present radiological appearances other than nodular formations.