局限期小细胞肺癌胸部放疗靶区的前瞻性随机对照研究

目的 通过开展前瞻性随机对照研究探讨局限期小细胞肺癌(SCLC)胸部不同放疗靶区对预后的影响。方法 选取2002-2017年中山大学肿瘤医院及浙江省肿瘤医院收治的接受2程EP方案诱导化疗后无疾病进展的309例局限期SCLC患者。随机分为照射化疗后残留肿瘤组(159例)和照射化疗前原发病灶组(150例)。2个组患者均采用累及野照射纵隔阳性淋巴结的完整结区。胸部放疗采用45 Gy分30次3周完成,2 次/d,与第3程EP方案化疗同步进行。共化疗4-6程。放化疗后疗效评价完全缓解及部分缓解的患者接受全脑预防性放疗25 Gy分10次2周完成或30 Gy分15次3周完成。采用Kaplan-Meier法分析生存数据。结果 照射化疗后残留肿瘤组和化疗前原发病灶组1、2、5年局部控制率分别为79.4%、61.5%、60.1%和79.8%、66.5%、57.3%(P=0.73)。化疗后残留肿瘤组和化疗前原发病灶组中位生存时间分别为22.1个月(95%CI:18.2~26.0)和26.9个月(95%CI:23.5~30.3),1、3、5、7年总生存率分别为81.1%、31.6%、23.9%、 22.2%和85.3%、36.6%、26.1%、20.0%(P=0.51)。化疗后残留肿瘤组和化疗前原发病灶组2-3级急性放射性食管炎发生率分别为32.9%和43.2%(P=0.01),2-3级肺纤维化发生率分别为2.0%和10.9%(P=0.01)。结论 对于诱导化疗后的局限期SCLC,胸部放疗可仅照射化疗后残留原发灶,纵隔淋巴结引流区可常规采用累及野放疗。

Final report of a prospective randomized study on thoracic radiotherapy target volumes for limited-stage small cell lung cancer

Objective In view of the controversy over radiotherapy target volume for patients with limited-stage small cell lung cancer (SCLC),a prospective randomized controlled trial was conducted to compare the impact of different radiotherapy target volumes on prognosis. Methods After 2 cycles of EP chemotherapy,patients without progressive disease were randomly assigned to receive thoracic radiotherapy (TRT) to either the post-or pre-chemotherapy primary tumour extent as study arm or control. Involved field radiotherapy (IFRT) to the entire metastatic lymph node regions was applied for both arms. TRT consisted of 45 Gy/30Fx/19 d administered concurrently with cycle 3 chemotherapy. Prophylactic cranial irradiation was administered to patients achieved complete or partial remission. Kaplan-Meier method was used for survival analysis. Results Between June 2002 and December 2017,159 and 150 patients were randomly assigned to study arm and control respectively. The 1-,2-,and 5-year local/regional control rates were 79.4%,61.5% and 60.1% respectively in the study arm versus 79.8%,66.5%,and 57.3% in the control arm (P=0.73).The median OS time was 22.1 months in the study arm (95%CI,18.2-26.0 months) and 26.9 months (95%CI,23.5-30.3 months) in the control arm,the 1-,3-,5-,and 7-year OS rates were 81.1%,31.6%,23.9% and 22.2% respectively in the study arm versus 85.3%,36.6%,26.1% and 20.0% in the control arm (P=0.51).Grade 2-3 acute esophagitis was developed in 32.9% and 43.2% of patients respectively in study arm and control arm (P=0.01),while grade 2-3 pulmonary fibrosis was observed in 2.0% and 10.9% of patients (P=0.01) respectively. Conclusions For patients with limited-stage SCLC who received induction chemotherapy,thoracic radiotherapy can be limited to post-chemotherapy tumour extent and IFRT can be routinely applied.