527例鼻咽癌患者调强放射治疗后第二原发癌的临床特征分析

目的 分析鼻咽癌患者调强放疗后第二原发癌的临床特征。方法 回顾性分析2007年1月至2011年12月行根治性调强放疗527例鼻咽癌患者的临床和随访资料,分析其调强放疗后第二原发癌的特征。结果 全组患者中位随访时间为45.5个月(4.0~97.0个月),出现第二原发癌12例,发生于照射野内、野外各6例,发生部位肺3例、舌2例、颈部2例、肾2例、脑1例、口腔1例、胃1例。全组患者第二原发癌1年、3年和5年累计发生风险率分别为0.4%、1.4%和3.1%,照射野内1年、3年和5年第二原发癌累计发生风险率分别为0.4%、0.8%和1.5%。不同性别、年龄、临床分期、放疗时间及有无化疗患者调强放疗后第二原发癌的累计发生风险率差异无统计学意义(P>0.05)。结论 上呼吸消化道是鼻咽癌调强放疗后第二原发癌最常见的发生部位,肺癌是最常见的第二原发癌。

Clinical characteriestics of second primary tumors in patients with nasopharyngeal carci-noma after intensity-modulated radiotherapy:series of 527 cases

Objective To analysze the clinical characteristics of second primary tumor in nasopharyngeal carcinoma(NPC) patients after intensity-modulated radiotherapy(IMRT). Methods Clinical characteristics and follow-up of second primary tumor in 527 patients with NPC after IMRT from January 2007 to December 2011 were analyzed retrospectively. Results During a mean follow-up of 45.5 months(4.0-97.0), 12 cases developed second primary tumor, and 6 cases occurred in the radiation field. The number of second primary tumor located in lung, tongue, neck, kidney, brain, oral or stomach was,respectively, 3, 2, 2, 2,1, 1 and 1. The cumulative risk of second primary tumor were 0.4% at 1 year, 1.4% at 3 year ,and 3.1% at 5 year, while they were 0.4%, 0.8% and 1.5% respectively in the radiation field. Sex, age, clinical stage, chemotherapy and radiation duration in NPC patients with IMRT were not related with the cumulative risk of second primary tumor(P>0.05). Conclusions Upper gastrointestinal tract is the most common site of second primary cancers in NPC after IMRT treament, and the most common cancer is lung cancer.