What term describes the change from one mature cell type to another and is associated with cancer?

Metaplasia refers to the process in which one differentiated cell type is replaced by another type that is better suited for a particular environment, often in response to chronic irritation or injury. This cellular change can be a precursor to more serious conditions, including cancer. In cancer pathology, metaplasia is noteworthy because the altered cell type can lose its original function and undergo further changes that may lead to dysplasia and eventually neoplasia, which is the uncontrolled growth characteristic of tumors.

For example, in the respiratory tract, chronic smoking can cause the normal columnar epithelial cells to transform into squamous cells, a classic instance of metaplasia. This adaptation can contribute to the risk of developing malignancies, particularly if the irritant remains present over time.

This concept contrasts with hyperplasia, which involves an increase in cell number and does not necessarily involve a change in cell type, and dysplasia, which indicates abnormal growth and differentiation within a tissue but does not inherently represent a change of one mature cell type to another. Neoplasia specifically refers to new, abnormal growth that can be benign or malignant but does not describe the process of cellular transformation as metaplasia does. Thus, metaplasia is the term that accurately