What term describes the loss of tissue differentiation and function in malignancies?

Anaplasia refers to the loss of tissue differentiation and function that is commonly associated with malignancies. In this context, it describes how cancerous cells become less specialized and more primitive in appearance and behavior compared to normal cells. Anaplastic cells often exhibit varied shapes and sizes, irregular nuclei, and a rapid rate of division, indicators that they have lost their normal characteristics and are no longer functioning in the way that healthy cells do.

The importance of anaplasia lies in its association with tumor aggressiveness; the more anaplastic a tumor is, the more likely it is to be invasive and to metastasize, reflecting a poorer prognosis for the patient. In contrast, terms such as atrophy, dysplasia, and hyperplasia denote different processes related to tissue growth and differentiation, none of which encapsulate the profound loss of differentiation characteristic of anaplasia. Atrophy involves a decrease in cell size or number, dysplasia refers to abnormal cell growth but not necessarily malignant, and hyperplasia signifies an increase in cell number, often in response to a stimulus but maintaining normal function.