The adenomatoid odontogenic tumour: ultrastructure of tumour cells and non‐calcified amorphous masses

Abstract

The ultrastructure of tumour cells and tumour droplets (TD, non-calcified amorphous masses) was studied in three cases of AOT using freshly prepared tissue. The fine structure of the epithelial tumour cells (cell type I-III) corresponded to that of earlier descriptions. The extracellular location of TD was clearly demonstrated. TD were of varying, sometimes bizarre, configuration. Some TD showed a homogeneous matrix; however, in addition most revealed electron-dense plaques. At high magnification, homogeneous types of TD showed only tubular elements; all others revealed granulo-tubular structures. The tubular elements were arranged concentrically. The nature of the TD is discussed and compared to former interpretations. From the present ultrastructural findings, it appears that the TD most probably represent some form of enamel matrix and as such may be considered a type of pre-enamel. Further studies are needed to elucidate the complex structure of the TD-material so characteristic of the AOT.

Study on the origin and nature of the adenomatoid odontogenic tumor by immunohistochemistry

“…Carmo and Silva 2 (1998) tried to correlate its clinical behavior with the cell proliferation rate assessed by AgNOR histochemistry. Philipsen and Reichart 14 (1999) considered AOT a non-invasive slow-growing benign lesion (hamartomatous). For Takahashi, et al 19 (2001) transferrin detection by immunohistochemistry in part of the tumoral cells indicated a neoplastic nature.…”

Adenomatoid odontogenic tumour in mandible in a 14-year-old boy

“…Moreover, eosinophilic, uncalcified and amorphous material can be seen, and is called ‘tumour droplets’. Some tumour droplets show a homogenous matrix whereas most tumour droplets reveal electron-dense plaques 14. In this case, tumour droplets are not seen.…”

Adenomatoid odontogenic tumor in pregnancy: A case report

“…Philipsen and Reichart considered AOT as a non-invasive slow-growing benign lesion [5] while Takahashi et al through their transferrin detection by immunohistochemistry revealed the neoplastic nature of the tumor [6].…”

“…Under histological examination, the tumor may be partly cystic and in some cases the solid lesion may be present only as masses in the wall of a large cyst. Moreover, eosinophilic non-calcified amorphous material can be found and is called "tumor droplets" which represent electron dense plaques or homogenous matrix [5].…”