Cyst or tumour?

This probably sounds like a silly question, ,but is there a difference between a cyst and a tumour?  My "friend" is a 15 cm complex cyst. Is the term tumour used only when referring to cancer?

[sdp4314]

Tumours can be both.  They don't make it easy for us, do they?


Shawn

[Barcelona]

I went into surgery to remove a "cyst", but after surgery they called it a benign tumor.  I was told that because my mass was not filled with liquid, it was a tumor.  I go for a follow up next week and they will have pathology results then, so I will ask more questions.