Cancer of the nasopharynx (that part of the throat between the back of the nose and the back of the mouth) is prevalent in Southeast Asia. It often causes no symptoms until locally advanced. In a study published in The New England Journal of Medicine on 10 August 2017, blood plasma samples from more than 20,000 men of Chinese descent aged 40 to 62 living in Hong Kong were tested for circulating DNA fragments of the Epstein-Barr virus. There were persistently positive results in 309 men who were then offered examination of their nasopharynx with an endoscope and by MRI scanning. Of the 300 men examined 34 (11%) were found to have nasopharyngeal cancer, and it was at an early and potentially curable stage in 16 of them.
Aspartate aminotransferase (AST) is an enzyme found in several parts of your body, including the heart , liver, and muscles. Since AST levels aren’t specific for liver damage, it’s usually measured together with ALT to check for liver problems. Your doctor may use an ALT-to-AST ratio to help with their diagnosis. When the liver is damaged, AST is released into the bloodstream. A high result on an AST test might indicate a problem with the liver or muscles. The normal range for AST is 8–48 U/L. Low AST is not indicative of any health issues.
Alkaline phosphatase is another liver enzyme that is frequently measured. This enzyme is usually found in the walls of the bile ducts (tube-like structures within the liver that connect liver cells together). Elevation of alkaline phosphatase may indicate an injury to the biliary cells. Common causes of biliary injury or biliary obstruction (cholestasis) are gallstones and certain medications, although, some of the conditions listed previously can also raise the levels of this enzyme. Alkaline phosphate is also found in the bone and can be elevated in bone diseases. GGT and 5' nucleotidase levels can be elevated in biliary conditions (disease of the gallbladder and bile ducts) along with alkaline phosphatase.