淋巴结转移率对胃癌预后价值的评价

Prognostic Value of Metastatic Lymph Node Ratio in Gastric Cancer Patients After Surgery

目的:评价淋巴结转移率(MLR)对胃癌术后患者预后的预测价值。方法:回顾性分析2004年至2006年间在我院就诊,临床资料完整的363例胃癌术后患者。按照第七版UICC/TNM(pN分期)及淋巴结转移率两种方法对淋巴结进行分期,比较两种方法评价胃癌预后的准确性及适用性,确定MLR分期方法的特点及优势。结果:363例胃癌术后患者按单变量生存分析方法将淋巴结转移率(MLR)分为四期:MLR0(0.0%)、MLR1(0-30%)、MLR2(30-70%)、MLR3(≥70%),其5年生存率分别为84.9%、58.3%、28.7%、12.9%,有显著性统计学差异(P<0.001)。pN分期分为pN0、pN1、pN2、pN3a、pN3b,其5年生存率分别为84.9%、60.8%、32.0%、21.9%、6.8%,有显著性统计学差异(P<0.001)。单因素COX生存分析后显示,MLR分期越高,预后越差(HR:MLR1,MLR2,MLR3/MLR0=1.589,4.455,9.900,P<0.001)。按清除淋巴结个数将所有病例分成两组:group1(≤15个)、group2(>15个),在该两组中比较pN及MLR分期的预后,结果显示pN3a在group1组中的5年生存率明显低于group2组(6.2%vs.38.4%,P<0.001),而MLR分期与清除淋巴结个数无统计学生存相关差异(P>0.05)。COX比例风险模型多因素分析表明,pN分期、MLR分期、肿瘤浸润深度、肿瘤分化程度均为影响预后的独立因素,以pN及MLR分期风险比最高。结论:MLR分期是评价胃癌术后患者预后的独立因素,该方法不受淋巴结清扫个数的影响,与pN分期方法相比,实用、准确、简单,可以降低pN分期因淋巴结清扫不足造成的期别转移现象。

Objective： To evaluate the prognostic value of metastatic lymph node ratio by comparing with the 7th AJCC, UICC/TNM classification （pN） in patients with gastric cancer after surgery. Method： We retrospectively reviewed clinical and pathological data of 363 patients who had undergone curative surgery at our institution more than 5 years. The MLR was assessed into 4 categories： 0, 0-0.3, 0.3-0.7, 〉 0.7. The MLR classification was compared with pN classification in terms of the accuracy and valid value. Results： Both the MLR system and pN system were well classified patients with significantly different prognosis （P〈0.001）. Patients were divided into two groups： groupl （≤15 examined lymph nodes）, group 2 （≥15 lymph nodes）. Patients belonged to the group 1, the 5 year survival rate ofpN3a was significant lower than that in group 2（6.2 % vs. 38.4 %,P〈0.001 ）. While the 5 year survival of MLR in group 1 and group 2 had no significantly differences, P〉0.05. By the way of Cox proportional regression hazard model, the text revealed that the degree of dif- ferentiation, depth of invasion, MLR and pN staging system were independently prognostic factors. The main hazard of the two models was the lymph node classification. Conclusion： Our findings confirmed the role of MLR staging system as independent prognostic factors of survival in patients with gastric cancer surgically treated. The MLR staging system which was a more practical and effective approach to evaluate the prognosis with gastric cancer could decrease the staging immigration.