Whats the difference between a lipoma, infected lymph node, and cyst? i have a bump on my neck (left back side) and doc says its one of those 3.

Can be hard to tell: inflamed lumps like you mentioned can be difficult to tell apart clinically. A lymph node that is swollen is usually deeper in the tissue and the surface skin looks normal. A lipoma is usually not inflamed and is soft to touch and often slides around when pushed or manipulated. A cyst is fro a hair follicle and when they rupture are often inflamed and tender. A biopsy may be needed to find out