Abstract
Sarcomas generally metastasize to the lung, while extra-pulmonary metastases are rare. However, they may occur more frequently in certain histological sub-types. Bone metastases from bone and soft tissue sarcomas account for a significant number of extra-pulmonary disease. Resection of lung metastases is widely accepted as therapeutic option to improve the survival of oligometastatic patients but there is currently no literature supporting curative surgical management of sarcoma bone metastases. Most are treated on a case-by-case basis, following multidisciplinary tumour boards recommendations. One study reported some success in controlling bone metastases using radiofrequency ablation. Our goal was to assess the impact of curative resection of bone metastases from soft tissue and bone sarcomas on oncologic outcomes.
Extensive review of literature was done to evaluate epidemiological and outcomes of bone metastases in sarcoma. We examined our prospective database for all cases of bone metastases from sarcoma treated with surgical resection between 1990 and 2016. Epidemiology, pathology, metastatic status upon diagnosis, type of secondary relapses and their treatments were recorded.
Overall survival and disease-free survival were calculated and compared to literature.
Thirty-five patients were included (18 men, 17 women) with a mean age of 46 years. Fifteen were soft tissue (STS) and 20 were bone (BS) sarcomas. Most STS were fibrosarcomas, leiomyosarcomas or UPS while chondrosarcomas and osteosarcomas were the most frequent BS. Nine (60%) STS were grade 3, 4 (27%) grade 2 and one grade 1 (3%). Eight (23%) were metastatic upon diagnosis (6 lungs, 3 bone). Treatment of the primary tumour included wide excision with reconstruction and (neo)-adjuvant therapies as required. Margins were negative in 32 cases and micro-positive in 3 cases. Amputation occurred in 6 (17%) cases. Primary lung metastases were treated by thoracotomy and primary bone metastases by wide excision. First relapse occurred in bone in 19 cases (54%), lungs and bone in 7 cases, 5 in lungs and 4 in soft-tissues. Lung metastases were treated by thoracotomy and chemotherapy in 3 cases, chemotherapy alone in the remaining cases. Bone metastases were treated by wide resection-reconstruction in 24 cases, extensive curettage in 4. Soft tissue relapses were re-excised in 4 patients. Two amputations were required. All margins were negative except for the 4 treated by curettage. Fourteen second relapses occurred in bone, 7 were radically-excised and 2 curetted.
At last follow-up, 6 patients were alive (overall survival of 17%), with a mean survival of 57 months, a median overall survival of 42.5 months and a median disease-free survival (DFS) of 17 months. Overall survival was 17%, compared to an 11% 10-year survival previously reported in metastatic sarcomas. Median disease-free survival was better in this study, compared to 10 months in literature, so as median OS (42.5 months vs 15). Three patients were alive with no evidence of disease. DFS, OS and median survival seemed to be improved by bone metastases wide excision and even if several recurrences occur, curative surgery with adjuvant therapies should be considered.
