pancreas

I noticed that hemoptysis is a symptom of pancreatic cancer. I thought this happens because, as the cancer grows, it compresses on the nearby blood vessels - but I don't understand how compression of abdominal blood vessels can cause hemoptysis. Could someone please explain this to me. Thanks!

Anybody do the Khan Academy passage called https://www.khanacademy.org/test-prep/mcat/biological-sciences-practice/biological-sciences-practice-tut/e/the-role-of-alcohol-abuse-in-pancreatitis I had a question regarding the answer to this question