Hi. how would you know if a particular tumor is benign or malignant without doing biopsy? it's movable, smooth and sometimes with pain.

Need more info: Some times the history of the lesion can give you a clue, but saying that when in doubt the gold standard is a biopsy to make the diagnosis .

Cant tell: presence of a tumor mass, moveable or even fixed and smooth with occasional pain can give an impression of benign or malignant made on physical only. To determine benignity or malignancy and tumor type can only be made on bx. Certain lesions can be clinically defined as malignant but need bx for therapy.