鼻咽癌病人放疗前后VCA—IgA抗体及EB病毒DNA水平变化

目的检测鼻咽癌病人放疗前、放疗1个疗程及放疗结束后血清EB病毒衣壳抗原IgA（VCA—IgA）抗体水平及EB病毒DNA（EBVDNA）载量的变化，探讨其在鼻咽癌疗效监测及预后评估中的价值。方法收集EBV阳性鼻咽癌病人放疗前、放疗1个疗程及放疗结束后的血清标本，提取外周血细胞DNA。应用ELISA试剂盒检测血清VCA—IgA抗体水平的变化，实时荧光定量PCR方法检测EBVDNA载量的变化。结果22例鼻咽癌病人3个不同放疗阶段血清VCA—IgA抗体和EBVDNA水平比较差异均有显著性（F=3．305、9．461，P〈O．05）。放疗结束后VCA-IgA抗体水平显著低于放疗前水平（t=2．081，P〈O．05），而放疗1个疗程后与放疗前及放疗结束后相比差异均无显著性（P〉0．05）。7例病人从治疗开始至治疗结束均未检测到EBVDNA，其余15例病人EBVDNA载量放疗前与放疗1个疗程及放疗结束后相比差异均有显著性（t=2．47、4．34，P〈0．05），而放疗1个疗程和放疗结束后相比差异无显著性（P〉0．05）。结论同时检测血清中EBV抗体及EBVDNA水平有助于鼻咽癌疗效监测及预后评估。

CHANGES OF EPSTEIN-BARR VIRUS DNA AND VCA-IgA TITERS DURING RADIOTHERAPY OF NASOPHARYNGEAL CARCI-NOMA

Objective To detect EBV VCA-IgA and EBV DNA before, after one course and at the end of radiotherapy in patients with nasopharyngeal carcinoma （NPC） and assess their value in monitoring the efficacy and predicting the prognosis of the disease. Methods Blood samples from EBER1 positive patients were collected before, after one course and at the end of the ra- diotherapy, peripheral blood cell （PBC） DNA was extracted. Serum VCA-IgA was detected by using enzyme linked immunosor- bent assay （ELISA）, and EBV DNA by real-time PCR. Results A comparison between the levels VCA-IgA and EBV DNA in three different stages of radiotherapy showed a significant difference （F= 3. 305,9. 461;P〈0.05）. The level of VCA-IgA upon completion of radiotherapy was much lower than that before radiation （t= 2. 081, P〈0.05）, but there was no significant differ- ences after one course of radiotherapy as compared with before and after completion of the therapy （P〉0.05）. Of the 22 patients, EBV DNA load was detected in 15, except eight patients, the differences of EBV DNA load among before, after one course and completion of the therapy were significant （t= 2.47,4.34;P〈0.05）, but the difference of that between one-course therapy and upon completion of the therapy was not significant （P：〉0.05）. Conclusion Simultaneous detection of serum VCA-IgA and EBV DNA is conducive to monitor of curative effect and assessment of prognosis of patients with NPC.