Editing Cholangiocarcinoma (section)

===Blood tests===
There are no specific [[blood test]]s that can diagnose cholangiocarcinoma by themselves. Serum levels of [[carcinoembryonic antigen]] (CEA) and [[CA19-9]] are often elevated, but are not [[sensitivity (tests)|sensitive]] or [[specificity (tests)|specific]] enough to be used as a general [[screening (medicine)|screening]] tool. They may be useful in conjunction with [[medical imaging|imaging methods]] in supporting a suspected diagnosis of cholangiocarcinoma.<ref>Studies of the performance of serum markers for cholangiocarcinoma (such as carcinoembryonic antigen and CA19-9) in patients with and without primary sclerosing cholangitis include the following:
* {{cite journal | vauthors = Nehls O, Gregor M, Klump B | title = Serum and bile markers for cholangiocarcinoma | journal = Seminars in Liver Disease | volume = 24 | issue = 2 | pages = 139–54 | date = May 2004 | pmid = 15192787 | doi = 10.1055/s-2004-828891 | s2cid = 260316851 }}
* {{cite journal | vauthors = Siqueira E, Schoen RE, Silverman W, Martin J, Rabinovitz M, Weissfeld JL, Abu-Elmaagd K, Madariaga JR, Slivka A, Martini J | display-authors = 6 | title = Detecting cholangiocarcinoma in patients with primary sclerosing cholangitis | journal = Gastrointestinal Endoscopy | volume = 56 | issue = 1 | pages = 40–7 | date = July 2002 | pmid = 12085033 | doi = 10.1067/mge.2002.125105 }}
* {{cite journal | vauthors = Levy C, Lymp J, Angulo P, Gores GJ, Larusso N, Lindor KD | title = The value of serum CA 19-9 in predicting cholangiocarcinomas in patients with primary sclerosing cholangitis | journal = Digestive Diseases and Sciences | volume = 50 | issue = 9 | pages = 1734–40 | date = September 2005 | pmid = 16133981 | doi = 10.1007/s10620-005-2927-8 | s2cid = 24744509 }}
* {{cite journal | vauthors = Patel AH, Harnois DM, Klee GG, LaRusso NF, Gores GJ | title = The utility of CA 19-9 in the diagnoses of cholangiocarcinoma in patients without primary sclerosing cholangitis | journal = American Journal of Gastroenterology | volume = 95 | issue = 1 | pages = 204–7 | date = January 2000 | doi = 10.1111/j.1572-0241.2000.01685.x | pmid = 10638584 | s2cid = 11325616 }}</ref>