Van Laethem J L, Bourgeois V, Parma J, Delhaye M, Cochaux P, Velu T, Devière J, Cremer M
Department of Gastroenterology, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium.
Gastrointest Endosc. 1998 Jun;47(6):479-85. doi: 10.1016/s0016-5107(98)70248-2.
Ki-ras mutation analysis from material collected during ERCP has been claimed to improve the diagnosis of pancreatic and bile duct carcinomas as compared with conventional cytology. Our aim was to study the relative contribution of both Ki-ras analysis and brush cytology in patients with a significant stricture at ERCP.
Brushings were collected in duplicate for both analyses in 142 patients in whom a definitive diagnosis was obtained by histology or a minimal follow-up of 6 months.
For pancreatic strictures, sensitivity, specificity, and accuracy of Ki-ras analysis vs. cytology in detecting malignancy were 81% vs. 66%, 72% vs. 100%, and 70% vs. 74%, respectively. For biliary strictures, they were 25% vs. 42%, 100% vs. 100%, and 35% vs. 43%, respectively. The combination of the two methods only marginally increased their sensitivity and accuracy in both types of strictures.
Ki-ras analysis is a sensitive method for diagnosing pancreatic but not biliary carcinoma. However, its specificity is lowered by a high frequency of Ki-ras mutations in patients with chronic pancreatitis (25%) who did not manifest cancer development within a 6-month follow-up period. In pancreatic duct strictures, brush cytology appears to be more specific in detecting malignancy; specificity for Ki-ras and cytology are equivalent for the diagnosis of malignant bile duct strictures. Therefore, making a clinical decision on the sole basis of Ki-ras analysis is probably not justified in the majority of the cases.
与传统细胞学检查相比，有人声称对经内镜逆行胰胆管造影（ERCP）采集的样本进行Ki-ras突变分析可改善胰腺癌和胆管癌的诊断。我们的目的是研究在ERCP检查时存在明显狭窄的患者中，Ki-ras分析和刷检细胞学检查的相对作用。
对142例患者进行重复刷检，用于两种分析，这些患者均通过组织学检查获得明确诊断或至少随访6个月。
对于胰腺狭窄，在检测恶性肿瘤方面，Ki-ras分析与细胞学检查的敏感性、特异性和准确性分别为81%对66%、72%对100%、70%对74%。对于胆管狭窄，它们分别为25%对42%、100%对100%、35%对43%。两种方法联合使用仅略微提高了两种类型狭窄的敏感性和准确性。
Ki-ras分析是诊断胰腺癌的敏感方法，但对胆管癌不敏感。然而，在6个月随访期内未发生癌症进展的慢性胰腺炎患者中，Ki-ras突变频率较高（25%），这降低了其特异性。在胰腺导管狭窄中，刷检细胞学检查在检测恶性肿瘤方面似乎更具特异性；Ki-ras分析和细胞学检查对恶性胆管狭窄诊断的特异性相当。因此，在大多数情况下，仅基于Ki-ras分析做出临床决策可能不合理。
