目的 探讨血清细胞角蛋白19片段(cytokeratin-19 fragment，CYFRA21-1)定量检测在鼻咽癌(nasopharyngeal carcinoma，NPC)的临床诊断和TNM和临床分期的意义。方法 用ELISA法测定112例NPC患者(NPC组)及93例良性疾病 组(良性对照组)血清CYFRA21-1浓度，并分析其在NPC诊断的敏感性、特异性，以及与NPC分期之间的关系。结果 NPC组患者血清CYFRA2l-1水平及阳性率显著高于良性对照组(P=0.000)，NPC组敏感性为66.1％，特异性为97.8%。 T4期、N2+N3期、M1期CYFRA21-1水平及阳性率分别高于T1期、N0+N1期、M0期(p<0.05)，N3组测定值水平及阳性 率分别显著高于N2、N1、N0组(p<0.05)，Ⅳ期测定值水平及阳性率分别显著高于Ⅱ、Ⅲ期(p<0.05)。T3+T4期、 Ⅳb期水平分别高于T1+T2期、Ⅳa期(p<0.05)。NPC组CYFRA21-1水平与T、N、临床分期之间均呈正相关(P值均小于 0.05)。结论 治疗前血清CYFRA21-1对于NPC的早期诊断及其与其他头颈部良性疾病的鉴别诊断有较高的价值，对于 评估NPC的进展情况具有一定的价值。

Objective To investigate the clinical significance of quantitative analysis of serum CYFRA21-1 for diagnosis and tumor TNM and clinical stages in nasopharyngeal carcinoma (NPC). Methods Pretreatment serum CYFRA21-1 in 112 firstly diagnosed NPC patients and 93 benign controls were measured by ELISA. Results The serum CYFRA21-1 positive rate of NPC was 66.1%.The level and positive rate of serum CYFRA21-1 in NPC group are significantly higher than those in controls respectively(P<0.05).The level and positive rate of serum CYFRA21-1 in T4, N3 and M1 group were significantly higher than those in T1,N2,N1,N0 and M0 group, respectively(p<0.05).The level of serum CYFRA21-1 in T3+T4 group was significantly higher than that in T1+T2 group(p<0.05).In the clinical staging,the level and positive rate of serum CYFRA21-1 in IV group were significantly higher than those in II,III group respectively(p<0.05),and the level of serum CYFRA21-1 in the IVb subgroup were also higher than the IVa subgroup(p<0.05).The level of serum CYFRA21-1 in NPC group positively correlated with the T,N classification and clinical stages. Conclusion Pretreatment serum CYFRA21-1 level has clinical value for diagnosis,differential diagnosis,tumor staging in NPC.