[Pneumatosis cystoides intestinalis in a patient with lung cancer].

We report a case of pneumatosis cystoides intestinalis (PCI) in a patient with lung cancer. A 60-year-old woman was admitted with multiple lung tumors and multiple brain tumors. She was given steroid hormones to reduce her brain edema. Total resection of a brain tumor yielded a pathological diagnosis of metastatic squamous cell carcinoma. During treatment, X-ray and CT images revealed intestinal pneumatosis and free air in the abdominal cavity, but a physical examination revealed no abnormal findings. She was given a diagnosis of PCI, and received conservative treatment. Her intestinal gas cysts and intra-abdominal free air disappeared spontaneously. PCI is an uncommon but important condition in which gas is found in a linear or cystic form in the submucosa or subserosa of the bowel wall. It is important to consider PCI as a possible complication in lung cancer patients who are given steroid hormones and systemic chemotherapy in the long-term.