Clinical Analysis Of 35 Cases Of Radiation Encephalopathy In Nasopharyngeal Carcinoma

Objective Through nasopharyngeal carcinoma clinical data of 35 patients were retrospectively analyzed for Radiation encephalopathy occurred after radical radiotherapy, and discussed the occurrence rules of Radiation encephalopathy and clinical characteristics, as to provide theoretical basis for the occurrence and development of Radiation encephalopathyMethod Collected January 2008 to December 2011 in the first affiliated hospital of guangxi medical university branch line of nasopharyngeal carcinoma radiotherapy after radical radiotherapy treated first occurs the clinical data of 35 patients with radiation encephalopathy, statistics into the group of patients age, sex, when the first stage, treatment, total dose, dose of REP site-related factors, such as volume, whether chemotherapy were analyzed. All patients were provided by nuclear magnetic resonance imaging(MRI) diagnosis. Count data by chi-square test, measurement data using t test; Survival analysis using Kaplan Meier method, compare the Log-rank test methods, nonparametric test using Wilcoxon rank and inspection, using Pearson correlation rank correlation analysis, through SPSS 16.0 statistical software for statistical analysis, the inspection level of a= 0.05, P< 0.05 for the difference was statistically significant.Result1. In our hospital, REP rate is 8.04%,,male:female=2.5:1, radiation encephalopathy is apart from the radiation of the end of the time for the first time for 15-83 months and the median time of 47 months, of which 6 to 12 months is 0,12 to 24 months was 8.6%(3/35),24 to 36 months was 14.3% (5/35),36 to 48 months was 34.3%(12/35),48-60 months was 22.9%(8/35), 60-72 months was 14.3%(5/35),72-84 months was 5.7%(2/35), the main time REP occured at the end of the radiation most likely three to four years,91.4% REP patients at the end of the radiotherapy 2 year.2. To February 4,2016, the total follow-up rate of the patients into the group reached 100%. Clinical symptoms:significant memory loss in 23 cases (65.7%), headache in 19 cases (54.3%) and 9 cases of bulbar paralysis symptoms (25.7%), dizziness, nausea and vomiting (8 cases) (22.8%), decreased visual acuity in 6 cases (17.1%), limb weakness, numbness in 5 cases (14.3%),3 cases of epilepsy (8.6%), and diplopia in 3 cases (8.6%) and facial sensory abnormalities in 2 cases (5.7%).3. According to the international union of cancer (UICC) staging of nasopharyngeal carcinoma (NPC) in 2010 into the group of patients during the initial stage, T2 patients accounted for 11.4%(4/35), T3 patients was 34.3% (12/35), T4 patients accounted for 54.3%(19/35); NO patients in 22.9%(8/35), 25.7%(9/35) patients with N1, N242.5%(15/35) patients, patients with N38.6 (3/35); Stage Ⅱ 5.7%(2/35), the phase Ⅲ (13/35),37.1% %,IVa51.4 period (18/35), IVb5.7%(2/35); Late T stage (T3、T4) nasopharyngeal carcinoma patients are more likely to happen REP; N staging with the REP did not see obvious relationship.4. In the group of patientsby MRI diagnosis of temporal lobe necrosis type of injury, did not see the brain stem, cerebellar damage, such as the temporal lobe is REP occurs most often.2D-CRT treatment group with IMRT treatment group in REP of 40.5 months and the median time distribution was 48 months, but there was no statistically significant difference (P=0.122>0.05). Confirmed REP died after 10 cases (28.6%),25 cases (71.4%), survival based on 2D-CRT treatment group and IMRT treatment group after REP deaths were 8 cases and 2 cases respectively, IMRT group survival curve of cumulative survival rate than 2D-CRT group that is high, but the Log-rank test of two kinds of treatment methods there was no statistically significant difference after REP survival time (P=0.527>0.05).After treatment with IMRT REP necrosis degree good after treatmen than 2D-CRT necrosis degreet (P=0.023<0.05). And CT-Sim group bilateral temporal lobe damage more (P=0.002).IMRT group REP post treatment of the median time from 2D-CRT group delay, survival time and the necrosis degree good, compared with the 2D-CRT should try to use the IMRT treatment5. IMRT treatment group, unilateral temporal lobe happened REP, maximum dose lateral temporal lobe injury suffered relatively unscathed side the maximum dose of comparative difference was statistically significant (P= 0.006), prompted IMRT treatment group caused by unilateral temporal lobe happened REP that dose factor is the main factor.2D-CRT treatment group, unilateral temporal lobe happened REP, on both sides of the temporal lobe largest dose comparison difference has no statistical significance (P=0.422), the correlation analysis on both sides of the dose has significant correlation (r= 0.997, P=0.997), prompted in 2D-CRT treatment group causes of unilateral temporal lobe disease may be related to other factors (immune factors, free radicals reaction and so on.6. REP focal necrosis area biggest point dose range fluctuations in 6709 cgy-8198 cgy, necrosis occur most often dose fluctuations in 76-78 Gy. And when the focal necrosis area dose≥76 Gy and<76 Gy when there are differences between the extent of necrosis (P=0.000).7. REP damaged and undamaged in patients with temporal lobe its V60, V65, V70, V75, V80, Domax differences have statistical significance. RTOG dose recommended temporal lobe 60 Gy or less, or V65< 1%, brainstem recommended dose 54 Gy or less, or its V60<1%. This study found there was no temporal lobe dose REP group were greater than 60 Gy, and V65 median volume was 7.98%, the V70 median volume was 2.95%; 35 patients did not cause the brain stem injury, but in the brain stem volume its V60=3.42%, V65 =0.87%, for the temporal lobe, brain stem limit dose to redefine.Conclusion1. T3, T4 in patients with nasopharyngeal carcinoma after radiotherapy is easy to occur REP;2. Nasopharyngeal carcinoma related REP mainly occurred in 36 to 60 months after the end of radiotherapy, the median time of onset was 47 months;3. Nasopharyngeal carcinoma associated REP showed significant time and dose dependence;4. The biological effect of a dose of more than 127Gy, it is possible to cause nasopharyngeal carcinoma related REP;5.2D-CRT is associated with more severe REP than IMRT.