Any abnormal lump or bump is considered a tumor. A tumor can also be referred to as a “mass”. The term “tumor” does not necessarily mean it is malignant or it is a cancer. In fact, the vast majority of hand tumors are benign or non-cancerous. Any lump or bump in your hand is a tumor regardless of what causes it.
Hand tumors can occur on the skin, like a mole or a wart, or can occur underneath the skin in the soft tissue or even the bone. Because there are so many tissue types in the hand (e.g. skin, tendon, fat, ligaments, bone, etc) there are many types of tumors that can occur. However, only a few of them are seen commonly.