Analysis Of Factors Influencing Local Progression Of Vertebral Metastases After Percutaneous Vertebroplasty(PVP)

Objective（s）:To investigate and analyze the risk factors of local development after percutaneous vertebroplasty（PVP）in patients with vertebral metastases;To explore the correlation and clinical significance between the index of"maximum bone cement diffusion cross-sectional area"and local progress after percutaneous vertebroplasty（PVP）.Methods:Clinical data of patients with spinal metastasis who underwent percutaneous vertebraplasty（PVP）in the Hospital from March 2017 to March 2022were retrospectively analyzed,A total of 89 patients,89 surgical vertebrae,Group by local progress or not,There were 26 cases of local progress,63 cases did not progress.The ages of the two groups were collecteddn,gender,Primary tumor type,Pathological compression fracture of the vertebra,The posterior margin of the vertebral body is intact,Postoperative radiotherapy and chemotherapy,Bone cement filling condition,Local progression time and image data,Horizontal CT images were obtained after operation,Select the layer with the largest cement area under the cross section,The ratio of bone cement cross-sectional area to vertebral body area under this level was measured,The maximum cross sectional area proportion of bone cement diffusion was calculated(S _{bone cement}/S _{vertebral body}),The average is obtained after many measurements.Postoperative observation index was pain core（VAS）,American Sinal Injury Association（ASIA）,Imaging progress,The patients were followed up for a long time,Local progressive symptoms and time were recorded.t test and x² test were used to analyze and compare the differences of each observation index between the two groups.Independent factors influencing local progress were analyzed by Logistic regression,With P<0.05 for the difference is statistically significant;Univariate analysis of local progression-free survival was performed using Kaplan-Meier’s Log-rank test,Univariate and stepwise regression analyses of local progression-free survival were performed by Cox regression analysis.Results:In group A,26 vertebral bodies developed locally after surgery（29.2%）,and in group B,63 vertebral bodies did not develop locally after surgery（70.8%）.The mean preoperative VAS was 8.35±1.90,and 24h postoperative VAS was significantly lower than preoperative VAS=2.05±1.67（P=0.0002）,There was no difference in visual simulation scores of pain before and 24h after surgery between group A and group B（P>0.05）.Univariate analysis showed that there were statistically significant differences in age,duration of last preoperative chemotherapy and interval of operation,frequency of postoperative chemotherapy,posterior edge destruction of vertebral body,and ratio of maximum bone cement diffusion cross section between the two groups（P<0.05）.In Logtisic regression analysis,age≥60years（P=0.044,OR=3.094）and maximum bone cement diffusion cross-section ratio>43%（P=0.048,OR=4.937）were independent factors affecting the local vertebral progression of patients with metastatic spinal cancer after PVP.Univariate Cox regression results showed that age（HR=3.140,P=0.006）,the number of postoperative chemotherapy（HR=0.279,P=0.038）,and the maximum cross-sectional area of bone cement diffusion（HR=3.042,P=0.017）had statistically significant effects on the local progression of spinal metastatic cancer after PVP.Multivariate stepwise Cox regression analysis showed that age（HR=3.140,P=0.006）was a risk factor for local progression of spinal metastatic cancer within 6 months after PVP.Among the 26 progressive vertebral bodies in group A,most of them had short-term local progression within 6 months after surgery（20 cases,76.92%）.Therefore,risk factors for local progression of affected vertebral bodies within 6months after surgery were analyzed.Univariate analysis showed that age,pathological compression fracture of vertebral vertebra and the proportion of maximum cross section of bone cement diffusion were the influencing factors of local progress within 6 months after surgery,with statistical significance（P<0.05）.Multivariate Logistic regression analysis showed that age≥60 years old（P=0.040,OR=3.408）and pathological vertebral compression fracture（P=0.043,OR=0.310）were independent influencing factors for local progression in patients with spinal metastatic cancer within 6 months after PVP surgery.Other variables influence on local progress has no statistical significance（P>0.05）.Univariate Cox regression showed that the maximum cross-sectional area ratio of bone cement diffusion（HR=3.432,P=0.017）,pathological compression fracture of operative vertebra（HR=0.348,P=0.025）,age≥60 years（HR=3.171,P=0.014）had a statistically significant effect on local progression within 6 months after PVP.Multivariate stepwise Cox regression analysis showed that age（HR=3.007,P=0.019）and pathological vertebral compression fracture（HR=0.369,P=0.034）were risk factors for local progression of metastatic cancer within 6 months after PVP。Conclusion（s）:PVP surgery can effectively improve the local pain in patients with metastatic spinal cancer.The main risk factors for local progression after PVP in patients with spinal metastatic cancer were age≥60,postoperative chemotherapy<4 times and maximum bone cement diffusion cross section ratio>43%,Patients aged 60 or older were more likely to have local progression.The risk factors for local progression within 6 months were age≥60 years and pathological compression fracture of the operative vertebra.