Adenoid Cystic Carcinoma

Common sites:

Gross features:

• small
• poorly encapsulated, infiltrative
• gray-pink

Histologic features:

• small cells arranged in tubular, solid, or cribriform patterns (reminiscent of cylindromas)
• most lumens are false lumens lined by myoepithelial cells, filled with hyaline
• some are true lumens lined by epithelial cells
• dark, compact nuclei
• scant cytoplasm
• spaces between groups of cells are often filled with hyaline material (excess basement membrane)
• tendency to invade perineural spaces

Immunophenotype:

Marker:	Sensitivity:	Specificity:
CD-117		Not specific
Alcian blue (true lumens)
PASD (hyaline)

Molecular features:

Other features:

• often recurs