Answer and Discussion of Quiz Set: A-006

4.    In a biopsy specimen that is suspicious of Barrett’s esophagus, some barrel shaped  columnar cells with cytoplastic mucin were found. Which of the following could be used to rule out the possibility of “pseudogoblet cells”?

A.  GMS stain

B.  PAS stain with and without diastase

C.  Alcian blue stain at pH 7.4

D.  Alcian blue stain at pH 2.5

E.  Mucicarmine stain

Answer and Discussion: The answer is (D). Goblet cells contain acid mucin. Alcian blue at pH 2.5 is used to detect acidic mucins, and it’s used to distinguish goblet cells from “pseudogoblet cells”. Mucicarmine stain does not dististinguish acidic mucin from non-acidic mucin. It should be noted that acid-mucin-positive non-goblet columnar cells could be present in the distal esophagus and gastroesophageal junction. The best examples are esophageal submucosal glands, reactive gastric foveolar cells, and gastric mucous neck cells. Histopathologic examination is still the gold standard for the diagnosis of intestinal metaplasia.