Very complex case with several important complications of immunotherapy/chemotherapy and graft versus host disease (GVHD).  

Benign pneumatosis is favored over ischemia due to the extent and distribution, lack of wall thickening (typical of ischemic colitis), lack of stranding/fluid, and risk factors from chemo/immunotherapy and GVHD resulting in increased mucosal permeability^2,4. 

Small bowel inflammation worsened since the baseline examination. Recent endoscopic biopsy confirmed GVHD. 

New soft plaque in the aorta is a very important finding that could be overlooked as simple atherosclerosis. However, it is NEW over just 2 months. Thrombus formation in the aorta has been described in the setting of chemotherapy/immunotherapy agents, particularly antiangiogenic agents¹. Aortic thrombus could also be related to altered procoagulant/defective fibrinolytic systems (the same risk factors for developing venous thromboembolism) in the setting of GVHD resulting in inflammatory cytokines, hematological malignancy (myelodysplastic syndrome in this case), or infection³.