Pneumatosis Intestinalis After Molecular-Targeted Therapy

Pneumoperitoneum after surgical manipulation of the abdomen implies a perforation. Rare cases of nonoperated cancer patients, largely with gastrointestinal or genitourinary cancers, have been noted to have radiologic findings of pneumatosis intestinalis and/or pneumoperitoneum as a complication of molecular-targeted therapy (MTT) without confounding factors for perforation. We present a patient with a cranial malignancy treated with bevacizumab who subsequently manifested with pneumatosis intestinalis.

A 67-year-old man with metastatic melanoma, non-small cell lung cancer, and recurrent cerebellar subependymoma was initiated on bevacizumab treatment for subependymoma recurrence. He subsequently underwent an uncomplicated ventriculoperitoneal shunt for progressive obstructive hydrocephalus, confirmed by a normal postoperative abdominal radiograph. One week later, he returned with worsening lethargy and a computed tomography consistent with pneumomediastinum and pneumoperitoneum. Due to concern for bowel perforation, the patient underwent diagnostic laparoscopy and removal of ventriculoperitoneal shunt. Focal sigmoid pneumatosis was identified without any signs of bowel perforation or ischemia. Bevacizumab was discontinued, and the patient's radiologic and clinical findings improved.

With increasing utilization of MTTs in brain tumor management, we raise MTT as a potential cause for pneumoperitoneum in neurosurgical patients. Pneumoperitoneum after extracranial procedures still requires workup and management for potential bowel perforation, but alternative causes such as bevacizumab should also be considered. Pneumatosis intestinalis patients on MTT can have benign physical examinations and will resolve, in the majority of cases, on discontinuation of the drug.