胃癌术中腹腔游离癌细胞检测临界值的确定及其临床意义

目的 探讨胃癌术中腹腔游离癌细胞(FCC)检测的最佳阳性判定值,以及腹腔FCC的存在对预后的影响.方法 用实时荧光RT-PCR方法检测术中腹腔FCC,并进行5年的随访.用MedCalc软件分析FCC最佳阳性判定值;[大于此值表示FCC存在,标记为FCC(+)],并前瞻性地分析FCC(+)组及(-)组与预后的关系.最后用多因素Cox回归模型分析影响预后的独立因素.结果 (1)最佳阳性判定值为31.21拷贝/mL时约登指数最高;(2)FCC(+)与(-)组的平均存活期分别为17.2个月和48.7个月,中位存活期分别为8.1个月和60.0个月;5年累积存活率分别为9.1%和67.4%.Kaplan-Meier生存分析显示,FCC(-)组生存时间明显长于FCC(+)组(P=0.000).Cox模型分析发现FCC,浆膜及远处转移是影响生存预后的独立因素(P＜0.05).结论 (1)FCC最佳阳性判定值为31.21拷贝/mL;(2)腹腔FCC是影响预后的独立危险因素之一,FCC(+)反映手术时肿瘤存在扩散状态.预示患者预后较差.

The optimal cut off value of CEA mRNA level for detection of free cancer cells in peritoneal washes and its clinical significance

Objective: To determine the optimal cut off value of  carcinoembryonic antigen (CEA) mRNA level for detection of  free cancer cells (FCC)  in peritoneal washes with real time PCR and its clinical significance.
Methods: The CEA mRNA levels in peritoneal washes from 65 cases of gastric cancer were detected by real time RT PCR. After 5 year follow up, cut off value of CEA mRNA level was obtained with the ROC curve analysis and the relationship between FCC and prognosis with Kaplan Meier method was studied.
Results: (1)With the ROC curve analysis, if the cut off value of CEA mRNA level was31.21,the Youden’s index was the  highest.(2)The mean survival time (months) in group of FCC(+),(-)was 17.2 and  48.7 months respectively, The median survival was 8.1 and 60.0 months, respectively, with significant difference (P= 0.000).The 5 year survival rate was  9.1% and67.4%，respectively. Compared with FCC(+) group, the FCC(-) group had significantly extended life span. COX regression showed that FCC was an independent prognostic factor.
Conclusions: (1) Our results suggest that the best cut off value of CEA mRNA levels for detection of FCC in peritoneal washes is 31.2 copies/mL; (2) This study shows that FCC is an independent factor that affects prognosis. FCC(+) denotes the presence of intraoperative tumor dissemination and predicts a poor prognosis.