Foveolar hyperplasia following partial gastrectomy results from expansion of surface mucous cell compartment.

Antrectomy with gastroenterostomy reconstruction is often associated with the development of foveolar hyperplasia and oxyntic atrophy. While a role for bile reflux in the etiology of foveolar hyperplasia is well established, the identity of the mucous cell lineages responsible for this condition have not been well characterized. We have studied three patients who demonstrated foveolar hyperplasia in their gastric remnant following antrectomy and gastroenterostomy. Mucosal samples were stained with antibodies against the trefoil peptides pS2 and hSP, to identify surface mucous and mucous neck cell lineages, respectively. Postoperative biopsies from all three patients showed oxyntic atrophy as documented by staining of parietal cells with antibodies against H/K-ATPase. All three patients demonstrated an exclusive expansion of pS2 immunoreactive mucous cells. The hSP staining cells were located deep in the expanded foveolar region. The results suggest that foveolar hyperplasia following antrectomy with gastroenterostomy results from a reactive hyperplasia of surface mucous cells. This pattern of surface cell hyperplasia is more consistent with a reactive expansion of mucous cells than with a response to chronic injury.