noun, plural: hamartomas or hamartomata
A hamartoma is a non-cancerous (benign) mass that forms from a faulty development in an organ. It is tumorlike and made up of disorganized tissue, or a mixture of cells that are normally present at the particular site. Since it resembles a neoplasm, it is not uncommon for a hamartoma to be misdiagnosed to a neoplasm. It may also be mistaken to a choristoma, which is also a tissue malformation but the cell components are not normally found at the site. For example, an excess pancreatic tissue in the duodenum is an example of choristoma. Examples of hamartomas are bone island tumors, osteopoikilosis, melorheostosis, osteopathia striata, osteochondroma, enchondromatosis, nonossifying fibroma, fibrous dysplasia, hemangioma of bone, and skeletal hemangiomatosis.
Hamartomas are usually benign and may not grow. However, they may still pose a health risk when they are involved in obstruction, infection, infarction, hemorrhage, fracture, and neoplastic transformation.
The underlying reason for the development of hamartoma is still not fully understood.
Word origin: Greek hamartia (“fault, defect”) + -oma (of a tumor or neoplasm)