The effect of pathological fractures on the prognosis of patients with osteosarcoma: a meta-analysis of 14 studies

// Yifei Zhou 1, * , Qian Lu 2, * , Jifeng Xu 3, * , Ruijian Yan 4, * , Junkun Zhu 5, * , Juntao Xu 6, * , Xuesheng Jiang 2 , Jianyou Li 2 and Fengfeng Wu 2 1 Department of Orthopedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China 2 Department of Orthopedics, Huzhou Central Hospital, Zhejiang University Huzhou Hospital, Huzhou, Zhejiang, China 3 Department of Orthopedics, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang, China 4 Department of Orthopedics, The Second Affiliated Hospital of Medicine College, Hangzhou, Zhejiang University, Zhejiang, China 5 Department of Orthopedics, Lishui Central Hospital, Lishui, Zhejiang, China 6 Department of Orthopedics, Huzhou Hospital of Traditional Chinese Medicine, Huzhou, Zhejiang, China * Authors contributed equally to this work and share co-first authorship Correspondence to: Fengfeng Wu, email: wufengfengzj@163.com Keywords: pathological fracture, osteosarcoma, meta-analysis Abbreviations: Newcastle–Ottawa scale (NOS), overall survival (OS), event free survival (EFS), relative risk (RR), confidence intervals (CI) Received: May 18, 2017 Accepted: August 07, 2017 Published: August 21, 2017 ABSTRACT Osteosarcoma is a leading cause of malignant tumor related death. We conducted a meta-analysis to evaluate the association between pathological fractures and prognosis in patients with osteosarcoma. We searched PubMed, Web of Science, and Embase for studies published until May 15, 2017. Crude and adjusted relative risk (RR) with 95% confidence intervals were used to compare data between the case and control groups. Fourteen studies and 3910 patients were included in the final meta-analysis. No statistically significant difference was detected between the pathological fracture and non-pathological fracture groups in local recurrences analysis (RR = 1.102, 95% CI: 0.813–1.495, P = 0.531); however, a statistically significant difference was found between group in distant metastasis (RR = 1.424, 95% CI: 1.089–1.862, P = 0.01). For survival rates, the following RRs were calculated: 3-year overall survival (OS) (RR = 0.736, 95% CI: 0.593–0.912, P = 0.005); 5-year OS (RR = 0.889, 95% CI: 0.791–0.999, P = 0.049); 3-year event-free survival (EFS) (RR = 0.812, 95% CI: 0.682–0.966, P = 0.018); and 5-year EFS (RR = 0.876, 95% CI: 0.785–0.978, P = 0.019). The pooled estimate of RR was 0.673 (95% CI: 0.364–1.244, P = 0.206) for local recurrence in the amputation and limb salvage groups. In conclusion, our analysis indicated that there were no differences in local recurrence and local recurrence after limb salvage between patients with or without a fracture. Additionally, the patients with pathological fracture had a higher risk of distant metastasis and lower 3-year OS, 5-year OS, 3-year EFS, and 5-year EFS. Considering the limitations of this study, we believe that future large-scale studies should be performed to confirm our conclusions.