The radiology corner. Is an air-fluid level within a gastric ulcer a reliable roentgen sign of benignancy?

A review of 108 cases of benign gastric ulcers and 33 ulcerated malignant gastric neoplasms showed that air-fluid levels were present within 25 benign ulcers and in only one malignant ulcer. These differences are statistically significant. Since, however, in unusual circumstances, a malignant ulcer may contain an air-fluid level, use of this roentgen sign alone to determine benignancy is not recommended. If used in conjunction with other accepted roentgen criteria, the presence of an air-fluid level within a gastric ulcer substantiates the diagnosis of benignancy in the majority of cases.