The Short-Term Effects And Prognostic Analysis Of NSCLC Brain Metastases Patients After Intensity Modulated Radiation Therapy

Objective: The purpose of this study was to evaluate the prognostic factors in Non-Small-Cell Lung Carcinoma(NSCLC)patients with brain metastases who received Intensity Modulated Radiation Therapy(IMRT)and discuss how its intracranial metastatic tumor volume would change.Materials and Methods: The retrospective analyses were conducted on the clinical data of 87 NSCLC patients with brain metastases and were admitted to our hospital during June 1st 2009 to June 30 th 2016 who accepted the brain intensity modulated radiation therapy.Patients with leptomeningeal metastases and those who underwent craniotomy or stereotactic radiotherapy before IMAT were excluded.To collect the age,sex,pathological type,number of intracranial metastases,molecular targeted therapy,total volume of intracranial metastases before radiotherapy and other clinical data.The survival rate was calculated by Kaplan-Meier method,and the Cox proportional hazards model was used to analyze the various prognostic factors.In addition,the brain MRI transection sequence images of the patients before radiotherapy and 1,3,6,9,12,15 months after radiotherapy were imported one by one into the Swedish Raystation treatment planning system.The intracranial metastases shortest diameter of the target lesions is more than 5mm,then select less than 3 largest target lesions to sketch,and the system can automatically calculate the lesion volume.The total volume of intracranial target lesions before radiotherapy as a baseline,you can calculate the relative volume and volume retraction rate of target lesions on the reexamined brain MRI image at all points in time.The multi-factors analysis of the intracranial metastases volume retraction rate at 1 month post-treatment are counted by Logistic regression method.Results: Up to October 30 th 2016,the follow-up rate was 94.3%(82/87).In the 87 patients,there were 54 deaths,28 survivors and 5 loss to follow-up.The median follow-up time was 12 months.The median survival time was 15.9 months,and the survival rate was 80.7%,66.3% and 27.5% in 6,12 and 24 months.Cox regression multi factors analysis showed that gender(P=0.021),age(P=0.004),KPS score(P=0.001)and molecular targeted therapy(P=0.002)were independent factors influencing the prognostic.Female,the age was 57 or younger,the KPS scores are higher,and molecular targeted therapy were the favorite prognostic factors for the survival time.In 87 patients,the proportion of the intracranial metastases total volume retraction was 95.4%(83/87),and the tumor volume was reduced swiftly within the first month.The Logistic regression multi factors analysis showed that total volume(P=0.039)of intracranial metastases before radiotherapy is an independent factor that affect the intracranial metastasis total volume retraction rate at 1 month post-treatment.The intracranial metastases total volume before radiotherapy is less than 3cm3,the intracranial metastases total volume is more likely to shrink at 1 month post-treatment.Conclusion: Female,age younger than 57 years old,the KPS score is higher,and the molecular targeted therapy were associated with longer survival time.The parts lesions of NSCLC brain metastases after IMRT have high local control rate.The total volume of intracranial metastases before radiotherapy is less than 3cm3,the lesions volume of intracranial metastases is more likely to shrink at 1 month post-treatment.