The prevalence of
cholangiocarcinoma (CCA) in Southeast Asia is much higher than other areas of the world. Eating raw, fermented, or undercooked cyprinid fish, infected with the liver fluke, Opisthorchis viverrini sensu lato (sl), results in chronic biliary
inflammation, periductal
fibrosis, and increased
cancer risk. There may be associated
glomerulonephritis. The process of
infection is difficult to disrupt because eating practices have proven extremely difficult to change, and the life cycle of the fluke cannot be broken due to high prevalence in canine and feline reservoir hosts. Fecal analysis and
enzyme-linked
immunosorbent assay tests can be used to diagnose
opisthorchiasis. Diagnosis of CCA is complex, partly due to the lack of definitive imaging characteristics but also due to the difficulty of obtaining samples for cytology or histology. This
cancer has proven to be resistant to common
chemotherapy treatments and so the two avenues of treatment available are surgical resection and
liver transplantation, both requiring early detection of the
tumor for the best chances of success. Late presentation of symptoms reduces the chances of successful surgical intervention. While liver fluke
infections can be treated with
praziquantel, individuals will often become reinfected, and multiple
reinfections can be more harmful than a singular,
long-term infection. A key research on the detection and characterization of novel
biomarkers in all parts of the carcinogenic pathway for early diagnosis is needed.