FIGURES AND TABLES

FIGURE 1.

Neuroendocrine adenoma of the middle ear displaying a trabecular growth pattern composed of columnar cells with round-to-oval nuclei, 'salt-and-pepper' chromatin pattern, and eosinophilic, finely granular cytoplasm.

FIGURE 2.

Multiple architectural patterns are present in neuroendocrine adenomas of the middle ear. Upper left, solid growth pattern with plasmacytoid cells. Upper right, trabecular growth pattern with artifactual clefting. Lower left, infiltrative pattern. Lower right, organoid pattern.

FIGURE 3.

Single tumor displaying multiple growth patterns, to include infiltrative (upper right), organoid (upper central), solid, trabecular, and glandular.

FIGURE 4.

Glandular pattern with easily identifiable inner, flattened cellular layer, and an outer cuboidal-to-columnar layer. Note the lightly basophilic amorphous material present within the glandular lumina.

FIGURE 5.

Pagetoid spread within metaplastic middle ear mucosa or external ear canal mucosa.

FIGURE 6.

Glandular lumen with an inner flattened layer (arrows),surrounded by an outer cuboidal layer. Cytokeratin 7 immunohistochemistry (bottom left) highlights the inner epithelial layer.

FIGURE 7.

Human pancreatic polypeptide (left) and cytokeratin 7 (CK7; right) immunohistochemistry. Note the predominantly basilar staining pattern of the HPP and the inner, luminal pattern of the CK7.

Table 1 - Immunohistochemical Panel.

Table 2 - Clinical Features in Middle-Ear Adenomas.

Table 3 - Macroscopic Features of Middle-Ear Adenomas.

Table 4 - Microscopic Features of Middle-Ear Adenomas.

Table 5 - Immunohistochemical Panel Results.