Squamous morules in gastric mucosa.
An elderly white man undergoing evaluation for pyrosis was found to have multiple polyps in the fundus and body of the stomach by endoscopic examination. Histologic examination of the tissue removed for biopsy over a 2-year period showed fundic gland hyperplasia and hyperplastic polyps, the latter containing nests of immature squamous cells. These nests arose within superficial gastric glands and resembled squamous morules seen in benign endometrium. Previous reports of this type of squamous epithelium in gastric mucosa were not encountered in our literature review. This most probably represents a benign process since there is no evidence to support its relationship to the occurrence of either primary squamous cell carcinoma or adenosquamous carcinoma of the stomach.