[Surgical treatment of pulmonary metastases from osteogenic sarcoma-significance of aggressive resection of bilateral multiple metastases and tumors invading adjacent organs].

: The results of surgical treatment of pulmonary metastases from osteogenic sarcoma were analyzed. Total cases were 23 with mean age of 17.0 +/- 9.1. The number of operations were 46, and operative procedures consisted of pneumonectomy in 1, lobectomy in 3, partial resection in 37 and resection of adjacent organs in 5. The overall five-year survival rate from the first thoracotomy was 21%. This was significantly higher than prognosis of the previous cases with pulmonary metastases which were not resected (p less than 0.001). Three-year survival rate for the group with 5 or less metastases was 57%, whereas that for the group with 6 or more metastases was 0% (p less than 0.02). To assess both the number and the diameter of metastases, an index called number-size score (NS score) was introduced, which was the sum of the diameters of each metastatic lesion. The three-year survival rate for the group with NS score 6 or less was 73%, whereas that for the group with NS score 7 or more was 9% (p less than 0.001). Disease free interval, the time of operation and histological effect of chemotherapy were not significantly related with prognosis. There was no long-term survivor among the patients with resection of adjacent organs. In conclusion, an aggressive resection of pulmonary metastases from osteogenic sarcoma should be performed with intensive chemotherapy, but significance of the resection of multiple metastases more than 20 or tumors invading adjacent organs is doubtful.