鼻咽癌XRCC4基因第8外显子突变与临床分期及预后的关系

  目的  探讨XRCC4基因突变与鼻咽癌分期及放疗疗效的关系。  方法  选取68例病理确诊为鼻咽癌的鼻咽肿瘤活检新鲜组织标本，变性高效液相色法检测XRCC4基因突变情况，收集患者的性别、年龄、病理类型、肿瘤分期、生存等临床资料，分析XRCC4基因突变与临床分期、肿瘤局部复发、远处转移以及疾病相关死亡等关系。  结果  27例标本检出XRCC4基因存在第8外显子突变，突变率39.7%（27/68）。全组中位随访98（6~106）个月，XRCC4基因第8外显子突变与T分期有关，局部晚期患者（T₃~T₄）的突变率高于早期（T₁~T₂）（χ2=4.686, P=0.03），突变与N分期、临床分期、局部复发、远处转移、疾病相关死亡均无相关性。T分期、N分期、临床分期分别是影响局部复发、远处转移和疾病相关死亡的独立预后因素，而XRCC4基因突变对生存无影响。  结论  鼻咽癌组织中存在XRCC4基因第8外显子突变，这种突变与鼻咽癌的放疗疗效无关，但与T分期有关，考虑XRCC4基因突变可能参与了肿瘤发展的某个阶段。 

Relationship among XRCC4 Gene Exon 8 Mutation,Clinical Staging,and Prognosis in Patients with Nasopharyngeal Carcinoma

  Objective  The relationship among X-ray repair cross-complementing group 4 (XRCC4) gene mutations, clinical staging, and radio-therapeutic efficacy in patients with nasopharyngeal carcinoma (NPC) was determined.  Methods  The XRCC4 gene mutations were determined using denaturing high performance liquid chromatography in 68 NPC patients. Clinical data including gender, age, histological type, tumor stage (T staging), and survival of patients were collected. The correlations among XRCC4 gene mutation, clinical stages of the disease, local recurrence, distant metastasis, and disease-related death were investigated.  Results  Mutations in section 8 of the XRCC4 gene exon were detected in 27 NPC cases, with a mutation rate of 39.7% (27/68). The median follow-up period was 98 (6 to 106) months. The gene exon mutation was related to the T staging. The mutation rates were higher in the locally advanced NPC patients (T₃ to T₄) than in the early NPC patients (T₁ and T₂) (χ2 = 4.686, P=0.03). No correlation was observed among the XRCC4 gene exon mutation, nodal staging (N stage), clinical stage, local recurrence, distant metastasis, and disease-related death. The T, N, and clinical stages were the independent prognostic factors for local recurrence, distant metastasis, and disease-specific death, respectively. The XRCC4 gene mutation had no effect on the survival rate.  Conclusion  XRCC4 gene exon 8 mutation exists in NPC. This mutation has no relation with the prognosis of the disease but is well correlated with the T stage, which implies its probable involvement in selected stages of nasopharyngeal carcinoma pathogenesis.