Pathogenesis of salivary gland neoplasms: The concepts of histogenesis and morphogenesis

Abstract

Many features overlap between different salivary gland neoplasms (SGNs) and as a result, classifying them distinctly has always been challenging. The differences in pathogenesis give rise to variations in the histopathological morphology of the SGNs. More accurate classification of SGNs can be made if the underlying pathogenesis is adequately understood in these terms. The present review aims to elaborate on the classification of SGNs based on the concepts of histogenesis and morphogenesis. In tumor pathology, histogenesis corresponds to the origin of the neoplastic cells; whereas morphogenesis refers to the development of the shape of an organ. The type of cell in which neoplastic transformation has occurred governs the events that follow the initiation of the multistage process which results in neoplasia. Our review elucidates the pathogenesis of the salivary gland tumor to understand the resulting histopathology, tumor morphology, and cellular differentiation of the tumor which reflects the parent cell. It comprehensively covers histogenesis, morphogenesis, and their relevance to the common salivary gland tumors, along with a brief account of the immunohistochemical markers.