Risk Factors Involved In The Develoment Of Hemorrhage During Microwave Ablation Of Lung Neoplasms

Background and ObjectiveAffected by smoking,air pollution and occupational carcinogen,lung cancer incidence has become the highest among the incidence of all kinds of cancer.What was worse,lung is the second most common tumor metastatic site only to liver cancer.Surgical resection is the first choice for the treatment of early lung cancer and lung metastasis.However,most patients have been diagnosed in a late stage and most of the lung metastasis are multi-lesions,making lots patients lose the chance of surgery.At present,local thermal ablation therapy is an important supplementary therapy,with radiofrequency ablation(RFA)and microwave ablation(MWA)to be the most widely used therapy in clinical practice.Microwave ablation is less susceptible to the low conductivity and high impedance of the aerated lung tissue,and the aerated lung tissue is even better for the microwave conduction,which enables the microwave to produce greater ablation range.Microwave ablation has certain advantages over other lung tumor ablation methods as it is less likely to be influenced by the thermal sedimentation of blood vessels and the ablation time is short.Thermal ablation therapy for lung cancer is standing out than other therapies,such as radiotherapy,chemotherapy and surgery,because of its higher curative effect and lower side effect.Microwave ablation can not only reduce the tumor load,but also improve the life quality of the patients,which brings good news to patients with advanced malignant tumors who have lost the chance of surgery.Though this minimally invasive treatment is of high security,it can lead to postoperative complications.Bleeding is one of the common complications,which has an incidence rate ranging from 3% to 8%.Although the incidence is relatively low,massive hemoptysis is life-threatening.Previous reports of ablation postoperative complications are normally about pneumothorax,only a few reports are about the incidence and risk factors analysis of bleeding.In this study,the clinical data of all patients with pulmonary MWA are collected and analyzed to obtain the incidence,risk factors and treatment of postoperative hemorrhage.Methodologies1.This study investigated 83 MWA(microwave ablation)cases for lung tumor that were performed at our institution from May 2013 to September 2016 to determine the potential contributive factors to the hemorrhage.we try to establish a relation between hemorrhage and the age of the patients,coagulation function,tumor size,tumor blood supply,tumor location(puncture needle length),target skin distance,ablation time,ablation power and times of puncture in and out of the chest.2.Statistical analysis was performed using software SPSS 17.0.Correlational analysis of each related factors of the patients and the bleeding conditions during intraoperative and postoperative period was conducted.The Pearson correlation coefficients between each factor and bleeding conditions were calculated.Results1.In 83 patients with lung tumor MWA,operations were done successfully with no mortality.The incidence of bleeding was 16.87%(14/83);13 of 83 cases(15.66%)were needle bleeding;1 of 83 cases(1.2%)was pleural hemorrhage;1 of 14 cases(7.14%)was pleural hemorrhage;10 of 83 cases(12.04%)were hemoptysis;the rate of postoperative application of hemostatic drugs was 62.65%(52/83).2.The possibility of hemorrhage was strongly correlated with coagulation function,tumor location(the length of the ablation needle),the blood supply of the tumor,and the number of puncture.However,there was no significant correlation between bleeding with the age of patient,tumor size,target skin distance,ablation time and ablation power.Conclusions1.Bleeding is one of the common MWA postoperative complications for lung tumor.The incidence of bleeding is not high and massive hemoptysis is quite rare.As the clinical symptoms are normally mild,most patients do not need treatment or only need conservative treatment.However,sufficient attention should be paid to patients with massive bleeding.2.Risk factors for bleeding after local ablation for lung tumor include: poor coagulation,long needle length,abundant tumor blood supply and multiple puncture times.Coagulation is an independent risk factor for bleeding after ablation.Clinical significanceBleeding is an important factor which affects the prognosis of patients with lung cancer after ablation.Research on the risk factors of bleeding after MWA provides very useful information to do the preoperative evaluation of the patients,to figure out the precautions during operation,and to do the postoperative monitoring of the patients.