摘要分析同时型多发骨肉瘤（synchronous multifocal osteosarcoma，SMOS）的好发年龄、性别、发病部位、肿瘤学特征、以及不同治疗方式的存活时间。在医学常用外文数据库检索"multifocal osteosarcoma"，在医学常用中文数据库检索"多发骨肉瘤、多灶性骨肉瘤、多中心骨肉瘤"，时间选取1949至2020年，所有被检索的文献及参考文献均被用于分析，经文题、摘要、全文内容二次筛选，共筛选出80篇文献，将所涉及的同时型多发骨肉瘤患者作为研究对象，删除重复报告的病例；收集每例入选患者的性别、年龄、发病部位、碱性磷酸酶、病理类型、治疗方式、存活时间等。采用系统分析的方法对数据进行分项研究。将本例患者及从80篇文献中筛选出的263例，共264例同时型多发骨肉瘤患者纳入研究进行系统分析，发病年龄为2~70岁，平均16.17岁，高发年龄10~20岁；男女比例为1.76∶1。188例（92.16%，188/204）患者发病部位位于四肢。135例（95.10%，135/142）患者碱性磷酸酶升高。134例（76.14%，134/176）患者病理类型为成骨细胞型骨肉瘤。有3例患者合并低钙血症、2例患者合并贫血。15例放弃治疗的患者（15/58）平均生存时间为4.51月；23例化疗的患者（23/58），平均生存时间为8.97个月；11例术前化疗+手术治疗的患者（11/58），平均生存时间为16.17个月；9例新辅助化疗+手术+术后化疗的患者（9/58），平均生存时间为23.28月。同时型多发骨肉瘤较为罕见，恶性程度高，预后差，高发年龄为10~20岁，目前最有效的治疗方法是新辅助化疗+手术+术后化疗。

abstractsSynchronous multifocal osteosarcoma (SMOS) was analyzed for its predisposing age, sex, location, oncology characteristics, and survival time with different treatment. The key words about "multifocal osteosarcoma" had been used to search articles which includ Synchronous multifocal osteosarcoma patients databases from 1949 to 2020. The articles have been filtratedby title, abstract and full text. There were 80 articles used for thisstudy. All the patients were objects of thisstudy. Butthe same patients' data in different articles had not been used repeatedly. The patients' data had been collected as much aspossible, including age, location, treatment, survival timeand so on. All the patients' data had been used forsystematic analysis. All of the 80 articles and 264 patients had been studied. The mean onset age was 16.17 years old and the peak age of onset was 10-20 years old. The gender difference had been uncovered and the sex ratio was 1.76∶1. The incidence site of 188 patients (92.16%) was located in the extremities. Alkaline phosphatase was elevated in 135 patients (95.10%). The pathological type was osteoblastic osteosarcoma in 134 patients (76.14%). There were 3 patients with hypocalcemia and 2 patients with anemia. The mean survival time of 15 patients (15/58) who gave up treatment was 4.51 months. The mean survival time of 23 patients with chemotherapy was 8.97 months. The mean survival time was 16.17 months in 11 patients with preoperative chemotherapy and surgical treatment. Nine patients with neoadjuvant chemotherapy, surgery and postoperative chemotherapy had an average survival time of 23.28 months. Multiple osteosarcoma of the same type was rare, with high degree of malignancy and poor prognosis. The age of high incidence was 10-20 years old. Currently, the most effective treatment was neoadjuvant chemotherapy, surgery and postoperative chemotherapy.