Does high ca 19-9 blood test means cancer?

No: It's not the test used to diagnose cancer, but in the presence of certain cancers, this marker can be positive. It is used for monitoring of cancer progression especially in the course of treatment thereof.

NO: Ca 19-9 a carbohydrate associated tumor maker is elevated from normal range of 0-37 to very high levels in GI cancers used as a monitoring tool , ; to see the progress or recurrence after treatments ( pancreas , liver , stomach, colon etc ) also can have high levels in non cancer benign diseases , like pancreatitis, liver diseases , diabetes etc , so it does not mean cancer , .

Very likely: A very high CA19-9 is a strong evidence of cancer of the pancreas or , less often, of the stomach or bile duct system