sonogram endoscopy

I have been told that I have a cyst on the tail of my pancreas and the doctor wants to do a sonogram endoscopy.  How is this procedure helpful?  Can they only see a better picture of the cyst?  What is the percentage of pancreatic cysts that are malignang?

[boron]

With endoscopic ultrasound, it will be possible to say, is it an "empty" cyst or a solid tumor. Exact diagnosis still won't be possible. I think a biopsy of pancreas, with a needle through the abdominal wall would be needed - maybe it can be done just during your investigation, you should ask the doc.

About statistic, go and search, but how can this help you. We may all get some rare disease...