Significance of intrauterine gas demonstrated by computed tomography

The computed tomographic (CT) demonstration of gas in the parenchymal organs of the abdomen or in extraintestinal sites is a relatively specific sign of abdominal or pelvic abscess. However, we have found that the demonstration of intrauterine gas usually indicates underlying neoplasm, rather than abscess. We retrospectively reviewed 15 patients with intrauterine gas present on CT and found that 10 had malignant uterine neoplasms, two had colonic carcinoma invading the uterus, and three were without neoplasm. Only four of 15 patients had evidence of serious uterine infections. The amount of gas did not reliably distinguish abscess from malignancy. Bacterial metabolism of necrotic neoplastic tissue is probably the major mechanism responsible for production of intrauterine gas in patients with uterine malignancy.