Cholangiocellular carcinoma is a relatively rare malignant tumor, originating from cholangiocytes, with poor prognosis and late diagnosis. It is a malignancy with a variable biological etiology, numerous genetic and epigenetic changes. Its incidence in the Czech Republic is about 1.4 per 100,000 people per year. For good prognosis and long-term survival, early diagnosis with surgical treatment is important. In these cases, a 5-year survival rate is about 20-40 %. In the early diagnosis imaging methods and histopathological verification play an essential role, whereas laboratory oncomarkers are not yet sufficiently accurate. The same applies for genetic markers. This leads to the search of new molecular targets and the high effort in the introduction of cytological and molecular-biological methods with high specificity and sensitivity into routine practice. Current early diagnosis is based on the use of efficient imaging methods. The use of genetic testing, and especially knowledge of the molecular basis of this disease, will be of a great benefit. The observation of the association between the genetic pathways, IDH1, RAS-MAPK etc., and genetic mutations of genes, such as TP53, KRAS, SMAD4, BRAF, IDH1/2, may be significant. From the molecular point of view, it is also interesting to monitor oncogenic potential in HBV/HCV infection.