Abstract
We report four cases of tubular adenoma of the gallbladder with spindle cell
metaplasia. Three patients had solitary polyps in the gallbladder and the fourth
had multiple (three) polyps. Only one patient who had a polyp of larger size had
abdominal pain. Histologically, these tubular adenomas had characteristic
morular foci composed of short spindle cells. These spindle cell components
lacked intercellular bridges or cytoplasmic keratinization.
Immunohistochemically, the spindle cells stained positively for one or more
cytokeratins and negatively for vimentin, muscle actin and S-100 protein.
Spindle cells are considered to represent the metaplastic component of the
adenoma cells.