Conflicting findings have been reported on the survival and
Conflicting findings have been reported on the survival and function recovery between treatments of LSS and amputation in patients with osteosarcoma. Toward this end, a meta-analysis of published clinical trials was performed to compare the clinical efficacy of LSS and amputation treatments in terms of local recurrence, 5-year overall survival rate, and metastatic occurrence. Several studies have attempted similar meta-analysis ; however, the included studies were much smaller, and their scopes were restricted to specific therapies compared with this meta-analysis. Through more extensive osteosarcoma literature, this meta-analysis tries to give a comprehensive conclusion on the outcomes in osteosarcoma patients receiving LSS and amputation. Such information will help us determine the most appropriate osteosarcoma-treating method.
Material and methods
Discussion With the improved efficacy of chemotherapy, the number of patients with osteosarcoma who received LSS instead of amputation has significantly increased recent years [33–37]. Moreover, LSS benefits not only malignant primary osteosarcoma patients, but also high-grade, localized osteosarcoma patients. However, there are substantial studies showing that the survival rate and local recurrence between LSS and amputation for osteosarcoma have been conflicting [25,38]. In this study, it was concluded that patients treated with LSS had a similar local recurrence and a lower igf ir occurrence compared with those treated with amputation, which was identical with that of Yin  but with more expansive literature included in our study. In addition, we found that 5-year overall survival rate of patients treated with LSS was higher than those treated with amputation. Therefore, our results provide more comprehensive evidence to support LSS for the treatment of osteosarcoma patients. In the meta-analysis of local recurrence of LSS vs. amputation for the treatment of osteosarcoma, there was no significant difference in the two surgery methods (OR: 1.03 with 95% CI ranging from 0.65 to 3.30; Z=0.14, P=0.89) (Table 3; Fig. 3). In five of 17 articles, the local recurrence rate in patients undergoing LSS was dramatically higher than those receiving amputation [15,19,23,25,29]. The sample sizes of these five studies were relatively small. Differently from these studies, other included studies revealed similar local recurrence rates between the two surgery methods. Moreover, in a study of Bacci et al.  with more than 500 samples investigated, local recurrence rates were found to be similar between LSS and amputation, which offered solid evidence to evaluate the local recurrence of LSS for the treatment of osteosarcoma. In this meta-analysis, the overall survival at 5 years was slightly better in those treated by LSS than those who had amputation(OR: 1.47 with 95% CI ranging from 1.10 to 1.97; Z=2.61, P<0.05)for treating osteosarcoma patients. Among the included studies, only two studies of Xu et al., Hegyi et al. [21,29] found that the amputation resulted in better 5-year survival. Abudu et al.  found that amputation didn’t come with a prolonged overall survival, though it provide better eradication of local tumor than LSS. However, in another article which was not included in the meta-analysis , it was indicated that LSS did not affect the survival rate. Even through our analysis results were somewhat inconsistent with previous research, we still concluded that LSS had a similar 5-year overall survival rate to that of amputation. The metastatic occurrence rate for patients treated with LSS was significantly lower than those treated with amputation (OR: 0.24 with 95% CI ranging from 0.10 to 0.60; Z=3.05, P<0.05) (Table 5; Fig. 5), which was identical with the results of Yin et al. . However, only 4 of 17 studies reported the metastasis, including 125 patients. Abudu  found that the treatment of LSS or amputation influenced the development of metastases to some degree, 44% in patients with LSS and 69% in patients with amputation; Niu  reported that metastasis happened in 25% patients treated with LSS compared with 60% in patients treated with amputation; in the study of Mavrogenis et al. , one of 23 patients receiving LSS developed metastasis while 3 of 19 patients receiving amputation did; in another study, one of 13 patients undergoing LSS had metastatic occurrence and 4 of 8 patients undergoing amputation had metastatic occurrence . Our analysis of metastatic occurrence was based on only four articles. There are some important prognostic factors of osteosarcoma, such as radical resectability of the tumor, extent of disease at diagnosis, initial tumor volume, and response to neoadjuvant chemotherapy, which makes the comparison of the two surgery methods complicate. Thus, additional high-quality, randomized controlled studies are needed to confirm the conclusions.