What are tumor-like lesions to be distinguished from true tumors?

Heterotopia is applied to microscopically normal cells or tissues that are present in abnormal locations. Ex: a rest of pancreatic tissue found in the wall of the stomach or small intestine, or a small mass of adrenal cells found in the kidney, lungs, ovaries, or elsewhere. These heterotopic rests are usually of little significance, but they can be confused clinically with neoplasms. •Hamartoma refers to an excessive, focal overgrowth of cells and tissues native to the organ in which it occurs. Although the cellular elements are mature and identical to those found in the remainder of the organ, they do not reproduce the normal architecture of the surrounding tissue. The line of demarcation between a hamartomaand a benign neoplasm is often unclear