The computed tomographic appearances and clinical significance of intussusception in adults with malignant neoplasms.

The computed tomography (CT) appearances of intussusception in 14 patients and the clinical follow-up of this condition in 17 adults with known primary malignant neoplasms were retrospectively reviewed. The ages of the 11 men and six women ranged from 25 to 83 years. Nine patients had been treated for malignant melanoma and the others for various primary neoplasms. Intussusception on CT was characterized by thickening of the affected bowel segment in all 14 patients and by the presence of intraluminal fat density material in 13, a concentric ring or "target" lesion in four, and an intra-luminal soft-tissue mass in nine. Five patients had intussusception, without other evidence of disease, caused by metastases in three patients, lipoma in one and idiopathic in one. Eleven of the other 12 patients had extensive disease, and one had small bowel cytomegalovirus infection. Five of these patients had more than one site of bowel involvement. Ten of the 12 patients had progression of disease on follow-up CT examinations and six died between 26 days and 7 months after diagnosis of intussusception. Intussusception may occur as the first indication of tumour recurrence or metastasis, but is more commonly a manifestation of widespread disease. However, even in patients with malignant neoplasms, it may be idiopathic or a result of benign neoplasm.