Solitary pulmonary metastases at first recurrence of osteosarcoma: Presentation, treatment, and survival of 219 patients of the Cooperative Osteosarcoma Study Group

BACKGROUND: To evaluate patient and tumour characteristics, treatment and their impact on survival in patients with a solitary pulmonary metastasis at first relapse of high‐grade osteosarcoma. PROCEDURE: Two‐hundred and nineteen consecutive patients who had achieved a complete surgical remission and then developed a solitary pulmonary metastasis at first recurrence of high‐grade osteosarcoma were retrospectively reviewed. RESULTS: Two hundred and three (94.9%) of 214 patients achieved a second complete remission. After a median time from initial diagnosis of osteosarcoma to first relapse of 2.3 years (range, 0.3–18.8 years), actuarial post‐relapse overall survival after 2 and 5 years was 72.0% and 51.2%. Post‐relapse event‐free survival was 39.1% and 31.1%. Median follow‐up time was 3.2 years (range, 0.1–29.4 years). A longer time until first relapse and diagnosis due to imaging were positive prognostic factors in uni‐ and multivariate analyses, as were a second complete surgical remission and, in regard to death, the absence of a subsequent relapse. The use of salvage chemotherapy and radiotherapy were not associated with patient outcomes, nor was the surgical approach (thoracoscopy vs. thoracotomy) nor the exploration (uni‐ vs. bilateral). CONCLUSION: Approximately half of the patients who experience a solitary pulmonary relapse at first recurrence of osteosarcoma remain alive 5 years after this first relapse. Only one third will remain disease‐free. A complete surgical resection of the lesion is essential for long‐term survival while relapse chemotherapy does not seem to improve survival. Innovative therapies are required to improve outcomes.