stedman 's medical dictionary defines a hamartoma as : ' a focal malformation that resembles a neoplasm grossly and even microscopically , but results from faulty development in an organ ; it is composed of an abnormal mixture of tissue elements , or an abnormal proportion of a single element , normally present in that site , which develop and grow at virtually the same rate as normal components , and are not likely to result in compression of the adjacent tissue ( in contrast to neoplastic tissue ) . '
C0018552
hamartoma
C0027651
neoplasm