摘要Objective:To investigate the serum lipid profiles of patients with localized osteosarcoma around the knee joint before and after neoadjuvant chemotherapy.Methods:After retrospectively screening the data of 742 patients between January 2007 and July 2020,50 patients aged 13 to 39 years with Enneking stage Ⅱ disease were included in the study.Serum lipid levels,including total cholesterol(TC),triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),lipoprotein-α[Lp(a)],and apolipoprotein Al,B,and E(ApoA1,ApoB,and ApoE),and clinicopathological characteristics were collected before and after neoadjuvant chemotherapy.Results:The mean levels of TC,TG,and ApoB were significantly increased following neoadjuvant chemotherapy(16％,38％,and 20％,respectively,vs.pretreatment values;P＜0.01).The mean levels of LDL-C and ApoE were also 19％and 16％higher,respectively(P＜0.05).No correlation was found between the pretreatment lipid profile and the histologic response to chemotherapy.An increase in Lp(a)was strongly correlated with the Ki-67 index(R=0.31,P=0.023).Moreover,a trend toward longer disease-free survival(DFS)was observed in patients with decreased TG and increased LDL-C following chemotherapy,although this difference was not statistically significant(P=0.23 and P=0.24,respectively).Conclusion:Significant elevations in serum lipids were observed after neoadjuvant chemotherapy in patients with localized osteosarcoma.There was no prognostic significance of pretreatment serum lipid levels on histologic response to neoadjuvant chemotherapy.The scale of increase in serum Lp(a)might have a potential prognostic role in osteosarcoma.Patients with increased LDL-C or reduced TG after chemotherapy seem to exhibit a trend toward favorable DFS.