第一原发性舌癌和鼻咽癌放疗后第二原发性舌癌的比较分析

目的探讨放疗后第二原发性舌癌的临床特点及治疗效果。方法回顾性分析53例鼻咽癌放疗后第二原发性舌癌和252例第一原发性舌癌的临床和随访资料,比较其临床特点、治疗及预后。Kaplan-Meier方法计算累计生存率,Cox比例风险模型进行多因素分析。结果第二原发性舌癌与第一原发性舌癌患者的平均发病年龄、性别、原发灶大小、cTNM分期、肿瘤组织分化程度和远处转移发生率差异无统计学意义,而两组5年生存率、原发灶位置、临床和病理淋巴结转移率差异有统计学意义。多因素分析显示,患者年龄、颈淋巴结清扫、cTNM分期是影响舌癌预后的独立因素。结论鼻咽癌放疗后第二原发性舌癌在原发灶发生部位、临床和病理淋巴结转移率等方面有自身的特点,其预后差于第一原发性舌癌;但鼻咽癌放疗史不是影响舌癌患者预后的独立因素,对鼻咽癌放疗后第二原发性舌癌患者行手术或包含手术的综合治疗可能有利于其预后。

Comparison of primary tongue carcinoma with second primary tongue carcinoma after radiotherapy for nasopharynx cancer

Objective To investigate the clinical characteristics and prognosis of second primary tumor of tongue (SPTT) after nasopharyngeal carcinoma (NPCR) treated with radiotherapy. Methods Clinical data of 53 patients with SPTT after NPCR ( group A) and 252 patients with primary tongue carcinoma ( group B) were analyzed retrospectively with regard to clinical characteristics and survival rate ( Kaplan-Meier) ; and multivariate analysis was performed using Cox proportional hazards model. Results There was no significant difference between group A and group B(P>0. 05) in the presenting age, sex, tumor size, cTNM stage, tumor differentiation and the rate of distant metastasis. The overall 5-year survival rates were 41.6% in group A and 56. 3% in group B(x2= 4.40,P = 0. 0359) with a statistically significant difference between two groups. The differences of tumor location(x2 =61. 18,P=0.000) and rate of clinical (cN+ ,x2=6.846, P =0.009) or pathological lymph node metastasis ( pN + ,x2 = 3. 993, P = 0. 046) were also statistically significant between group A and group B, respectively. Multivariate analysis showed that age at presence, cTNM stage and with or without neck lymph node dissection were independent risk factors affecting survival. Conclusion Second primary tongue carcinoma after radiotherapy for nasopharyngeal carcinoma is likely to occur on the dorsal aspect of the tongue with worse prognosis but with a lower rate of lymph node metastasis than that of primary tongue carcinoma. However, radiotherapy history is not an independent influencing factor on prognosis. Surgical resection or combined modality therapy may give a better prognosis.