Clinical Result With Simultaneous Integrated Boost Intensity Modulated Radiation Therapy(SIB-IMRT)for Brain Metastasis Of Non-small Cell Lung Cancer

Objective To explore the response and safety with SIB-IMRT for 1-5 brain metastases of non-small cell lung cancer(NSCLC).Methods Two hundred and ninety-four patients of Non-small-cell lung cancer with 1-5 brain metastases were enrolled from July 2009 to July 2015,114 cases of the SIB-IMRTgroup,62 cases of the 3DCRT group,40 cases of the pure WBRT group and 10 cases of the pure local brain metastases radiotherapy group.To observe the efficacy and toxicity,through the Mini Mental State Scale(MMSE)and daily life ability scale(ADL)to evaluate the changes of quality of life between the SIB-IMRT group and the 3DCRT group after treatment.Result The response rate of the SIB-IMRT group,the 3DCRT group,the pure WBRT group and the pure local brain metastases radiotherapy group were 53.8%,42.9%,50%,and 42.9%,respectively,the 1-,2-year OS and MST were 47.9%and 45%,23.9%and 15%,0%and 0%,0%and 0%,16 months.12 months.9months and 7months,respectively.Stratified analysis showed the response rate of the SIB-IMRT group and the pure WBRT group were stastistically significant for 1-2 lesions of brain metastases(z=-0.892,P=0.011).The four groups in the intracranial recurrence and death factors were no ststistically significant.The mean duration of the SIB-IMRT group irradiation was 15.29 days,significantly shorter than other groups,there wasstastistically significant compared withother groups.The MMSE score had no different significantly in the two groups pre and post-treatment;Stratified analysis showed a downward trend after 3 month for 1-2 lesions of brain metastases in SIB-IMRT group and it can recovery after 6 month,while the 3DCRT group showed a downward trend post-treatment,it showed a Upward trend for 3-5 lesions of brain metastases in the two groups after treatment;The ADL score had stastistically significant in the SIB-IMRT group pre and after 1 month treatment(t=-2.459,P=0.017).it had no stastistically significant in the 3DCRT group pre and post-treatment;,Stratified analysis showed a upward trend after 1 month,but it would show a downward trend after 3 month for 1-2 lesions or 3-5 lesions of brain metastases in SIB-IMRT group and it can recovery after 6 month,and it showed a downward trend post-treatment for 1-2 lesions of brain metastases in the 3DCRT group but it showed a upward trend post-treatment for 3-5 lesions of brain metastases in the 3DCRT group.There was a stastistically significant in the incidence of acute toxicity between the SIB-IMRT group and the pure WBRT group in the central nervous system(P=0.019),but there was no stastistically significant compared with the 3DCRT group and the pure local brain metastases radiotherapy group.Conclusion SIB-IMRT technology is safety and effective,no influence on cognitive function and life of ability,the acute toxicity can be tolerated and significantly shorten the time of radiotherapy for patient with other treatment time.