Long-term Survival Following Radiofrequency Ablation of Lung Metastases in an Elderly Patient With Calcaneal Osteosarcoma: a Case Report and Review of the Literature

Abstract Background: Lung metastases are the primary cause of death from osteosarcomas. Complete resection of lung metastases can prolong the survival. However, complete surgical resection in elderly patients is often difficult due to high risk of peri-operative complications. Radiofrequency ablation (RFA) is a minimally invasive technique to destroy tumor nodules using heat. Here, we present an elderly patient with osteosarcoma in calcaneus a scapular osteochondroma, who metachoronusly developed multiple lung metastases. Subsequently, he has been surviving a relatively long period by the use of percutaneous computed tomography (CT)-guided lung RFA against his lung metastases.Case presentation: A 74-year-old male presented with 1-year history of heel pain. Imaging analysis demonstrated a mixture of osteolytic and osteosclerotic lesions in the calcaneus with extraskeletal lesions. The histology of the biopsy specimen showed osteoid matrix with malignant spindle cells, which was diagnosed as a conventional high-grade osteosarcoma. Below-knee amputation was performed. However, 6 lung metastases were found in both lungs 1 year after surgery. During 4.5 years from the initial percutaneous CT-guided lung RFA, 18 lung metastases were treated in 8 procedures. Lung RFA was performed under moderate sedation and local anesthesia. The most frequent complication was pneumothoraxes in 3 procedures followed by pleuritis with pneumothorax in 1 procedure. Chest tube drainage was required in 2 of 8 (25%) lung RF procedures. Mean duration of hospital stay for lung RFA was 5.3 ± 2.1 days (range, 3-10 days). The patient has been alive with disease for 5.5 years after initial surgery. Conclusion: Our experience indicates that lung RFA is effective for elderly patients with lung metastases of osteosarcoma without serious complications.