局限期小细胞肺癌预防性全脑照射的临床意义

Clincal study of prophylactic cranial irradiation on patients with limited small cell lung cancer in complete remission

目的探讨预防性全脑照射对局限期小细胞肺癌脑转移率和生存率的影响。方法46例经化疗加胸部放射治疗后完全缓解的局限期小细胞肺癌被随机分为脑照射组(23例)和对照组(23例)。全脑照射在完全缓解后第10～62天进行,采用双侧野对穿照射,常规分割照射,5次周,2Gy次,中平面剂量为30Gy。结果脑照射组脑转移率为13.0%,低于对照组的47.8%(χ2=5.03,P=0.025)。脑照射组1,3,5年生存率分别为82.6%、47.8%和39.1%,对照组分别为73.9%、30.4%和13.0%,两组比较差异有显著性(χ2=4.07,P=0.044)。PCI开始时间对生存率无影响,但对脑转移的发生有影响。生存期超过5年以上的脑照射组患者无严重的脑损伤后遗症。结论完全缓解的局限期小细胞肺癌行预防性全脑照射能减少脑转移发生率,提高生存率。PCI开始越早越好。

Objective To evaluate the efficacy of prophylactic cranial irradiation (PCI) on the survival and brain metastatic rates in patients with limited small cell lung cancer(SCLC) in complete remission(CR).Methods Forty-six patients with limited SCLC in CR after chemoradiotherapy were randomly divided into prophylactic cranial irradiation(PCI) group(n=23) and control(C) group (n=23).Patients in PCI group received irradiation at a dose of 30 Gy in 15 fractions of 2 Gy/fraction. Survival rates of the two groups were analyzed by Kapian-Meier and compared by Long-Rank, the difference of cranial metastases by χ~2 test.Results The clinical features of patients such as age,sex,means of treatment before PCI were similar between the two groups.The incidence of cranial metastases was 13.0% in PCI group in contrast to 47.8% in the C group with the difference significant (χ~2=5.03,P=0.025). The 1-,3-, 5-year survival rates was 82.6%, 47.8%,39.1% respectively in PCI group and 73.9%, 30.4%, 13.0% respectively in the C group (χ~2=4.07,P=0.044).The differences between the two groups of patients were statistically significant.Interval between CR and PCI was not significant on survival rates,but was significant on cranial metastases. No serious sequela was observed in patients of survival ≥5 years receiving PCI.Conclusion For patients with limited-stage SCLC in complete remission after chemoradiotherapy,PCI can decrease the incidence of cranial metastases and improve the survival rate.Early PCI is better than late.