36例鼻咽癌放疗后第二原发口腔鳞癌的临床分析

Clinical Analysis of Second Primary Oral Squamous Cancer in Patients with Nasopharyngeal Carcinoma after Radiotherapy

目的:探讨鼻咽癌放疗后第二原发口腔鳞癌的临床特点及影响预后的因素,并探索其治疗模式。方法:回顾性分析1990年12月至2005年12月15年间在中山大学肿瘤防治中心接受首次治疗的鼻咽癌患者12121例,其中发生第二原发口腔鳞癌患者共36例,采用Kaplan-Meier法计算累积生存率,Cox回归方法进行多因素分析。结果:随访至2010年7月,36例患者中死亡21例,Kaplan-Meier法统计接受治疗的36例患者总的3、5、10年生存率分别为38.9%、22.2%、11.1%。口腔鳞癌发生在舌23例,牙龈7例,硬腭3例,其他3例。单因素分析第二原发癌的T分期、N分期、临床分期及治疗方式是影响其预后重要因素,多因素分析淋巴结阳性是影响预后的独立因素结论:鼻咽癌放疗第二原发口腔鳞癌中发生舌癌的比例较高,T分期、淋巴结阳性是影响预后的独立因素;鼻咽癌放疗后5年要警惕第二原发癌的发生,对鼻咽癌放疗后第二原发口腔鳞癌进行早期诊断,行手术为主的综合治疗。

Objective： To investigate the clinical characteristics of second primary oral squamous cancer （ SPOSC ） in nasopharyngeal carcinoma （ NPC ） patients after radiotherapy. The related prognostic factors are also investigated. Methods： Data of 12,121 NPC patients admitted to the Cancer Center of Sun Yat-Sen University during the period January 1990 to December 2005 were retrospectively analyzed. Of these, SPOSC occurred in 36 cases after radiotherapy for NPC. The Kaplan-Meier curve was used to calculate the accumulated survival rate, and multivariate analysis was performed in these patients using the Cox proportional hazard model. Results： Of the 36 SPOSC patients, 21 died during the follow-up. The overall 3, 5, and 10-year survival rates of the 36 patients who underwent SPOSC treatment were 38.9%, 22.2% and 11.1%, respectively. Of the 36 cases, SPOSC in the tongue occurred in 23 cases, SPOSC in the gum were found in 7 cases, and SPOSC in the palate were found in 3 cases. Lesions at the other sites were seen in the remaining 3 cases. The univariate analysis showed that the major prognostic factors influencing the survival of the SPOSC patients were tumor size, N stage, mode of treatment, and clinical TNM staging. The multivariate analysis for risk factors of the positive lymph node was the independent factor affecting the prognosis. Conclusion： There is a high risk of SPOSC in the tongue after radiotherapy of NPC. Tumor size, pathological N stage, and treatment method are the independent factors affecting survival. Vigilance for SPOSC should be maintained for 5 years after radiotherapy of NPC. Our data indicate that early diagnosis and combined therapy, with surgery as the first choice of treatment for SPOSC, may lead to better survival rate and prognosis.