Histologic diagnosis and grading of esophageal acute graft-versus-host disease

Acute intestinal graft-versus-host disease (GvHD) is a serious threat after allogeneic hematopoietic stem cell transplantation (alloHSCT). Although criteria for the histological diagnosis and grading of GvHD are well established for most parts of the gastrointestinal tract, evidence-based criteria have not yet been defined for the esophagus. Here, we evaluated esophageal biopsies obtained from 51 patients who underwent alloHSCT and compared the findings with those within the stomach and duodenum. In 32 of 51 biopsy samples of the esophagus, we identified a continuum of histological features of acute GvHD, ranging from vacuolar degeneration and single-cell apoptosis to the formation of clefts and mucosa denudation in advanced cases. These findings correlated with GvHD involving the stomach and duodenum and the clinical manifestations of GvHD in other organs. We therefore conclude that acute GvHD and esophageal GvHD can be diagnosed and graded histologically. Our findings may help to establish the histological diagnosis of acute GvHD using endoscopic biopsies from the esophagus and to explain the alterations observed in the esophageal mucosa in patients after alloHSCT.