Gastric mucosal calcinosis: clinicopathologic considerations.

Generally, gastric mucosal calcinosis (GMC) is only rarely encountered in routine biopsies. GMC may be classified as dystrophic, metastatic, or idiopathic. Metastatic calcification represents the most frequently encountered subtype, and refers to the deposition of calcium salts on largely normal tissues in the setting of an abnormal serum biochemical environment (hypercalcemia, hyperphosphatemia, and/or an elevated CaxPO4 product). In contrast, dystrophic calcification implies calcification in inflammed, fibrotic, or otherwise altered tissue in the setting of a normal biochemical environment. The gastric mucosa, along with the kidneys and lungs, are preferential sites for metastatic calcification, a finding that has been attributed to the relative intracellular alkalinity at these sites. In addition to the wide variety of hypercalcemia and/or hyperphosphatemia-causing clinical conditions, GMC has also been associated with atrophic gastritis, hypervitaminosis A, organ transplantation, gastric neoplasia, uremia with eucalcemia/euphosphatemia, and the use of aluminum-containing antacids, citrate-containing blood products, isotretinoin, and sucralfate. Although GMC has rarely been associated with epigastric pain and/or dyspepsia, most come to clinical attention owing to their accumulation of bone-seeking radiopharmaceuticals or represent a postmortem finding. The precise significance or mechanistic basis for GMC remains to be elucidated. However, their presence in gastric biopsies should be reported, as they may serve as an indicator for generalized metastatic calcification, especially in organs where they may be fatal, such as the heart. Furthermore, some examples of systemic calcification are reversible with normalization of biochemical parameters, which highlights the need for pathologists to report this finding when encountered in a premortem gastric biopsy.