CA19-9 is traditionally taken as a cancer marker for the pancreas. This marker is unfortunately not specific and can also be found in patients with bile duct, stomach and colon cancers. Unknown to many, an elevation of this tumour marker is commonly seen in people with inflammation of the pancreas as well as bile duct obstruction due to stone disease.
As your CA19-9 is well within normal limits, there is no reason why you should be concerned especially if there is no risk factor such as personal or family history of cancers involving the liver, bile duct or pancreas. There is also no necessity for you to repeat the test.
There is an increasing trend for people to participate in health screening program these days and tumour markers are part of many of these packages. If there is no significant family history of cancers and you are not experiencing any symptom, my advice is to omit these markers which can create unnecessary worries and anxiety.
Do listen to your body and address symptoms which persist. Besides breast, cervical and colon cancer which should be screened after a certain age, most other cancers are not cost effective to be screened in the general population and cancer work-up is usually done for symptomatic cases only.