Abstract
A 67-year-old man with liver and retroperitoneal metastases from a gastrointestinal stromal tumor arising in the jejunum had been administered oral sunitinib for 2 months. He presented to our department with right-sided lower abdominal pain. His general condition was good, with no high-grade fever, and the other vital signs were also stable. Contrast-enhanced computed tomography was promptly performed, and pneumatosis cystoides intestinalis (PCI) was detected in a wide area around the ileocecal lesion. There were no signs of acute abdomen requiring emergency surgery due to conditions such as intestinal perforation, ischemia, or obstruction. Sunitinib was discontinued and the patient was placed on nil orally with intravenous infusion. PCI resolved promptly and the patient was discharged on the 21st day after admission. PCI is a rare side effect of sunitinib with only 8 cases reported previously, which can complicate with acute abdomen or gastrointestinal perforation, in some cases. Thus, the early identification of sunitinib as the cause of PCI is important. Although PCI is a rare adverse effect of sunitinib, clinicians must be aware of it to promptly provide the correct diagnosis and treatment.