Teaching Case

34-year-old male with chronic myeloid leukaemia, history of bone marrow transplant and graft vs host disease.  Presented with severe left upper quadrant pain and tenderness.  Splenomegaly on exam. Normal amylase and lactate, elevated CRP.

Abdominal and pelvic CT with oral and intravenous contrast was performed.  There is abnormal gastric wall thickening along the greater curve with hypoenhancement and loss of the normal rugal folds.  This extends beyond the expected margins of the gastric wall and there is loss of the fat plane between the greater curve of the stomach and the gastro-epiploic arteries.  Adjacent fat stranding extends into the greater omentum. No free air or rim-enhancing fluid collection.  The spleen is unremarkable in appearance.

Post-transplant lymphoproliferative disorder (PTLD) is a cause of significant morbidity and mortality in patients who are immunosuppressed followings solid organ or bone marrow transplant [1]. Early diagnosis is important as it may lead to an improved response to treatment; decreased immunosuppression alone can result in PTLD regression in 20-80% of cases [2]. Although GI tract involvement is relatively common (20-30%), involvement of the stomach is extremely rare [3].

The gastric wall is difficult to evaluate on CT, in part due to the variable appearance depending on the degree of distension. This can lead to both over-calling and under-calling abnormalities. Reviewing the stomach on coronal/sagittal reformats may improve accuracy [4]. 

When the stomach is under-distended, the gastric wall can appear markedly thickened.  However, the rugal fold pattern should be preserved, often hyperenhancing. In this case, the gastric wall is thickened but also appears homogenous and low in attenuation due to oedema.  The normal texture of the rugal folds is lost. Food or contrast in the stomach may also mimic a mass; however, this should be in a dependent position, not circumferentially involving the wall of the distal stomach.

Gastric ulceration without perforation is difficult to identify on CT. In this case, the key finding is the obliteration of normal planes. The abnormally thickened gastric wall abuts the gastro-epiploic vessels with obliteration of the intervening fat plane, indicating a more aggressive process.

In this case, diagnosis was confirmed on endoscopy and biopsy.

All patient data have been completely anonymised throughout the entire manuscript and related files.