Gastric DNA content in postgastrectomy patients. Relationship to mucosal dysplasia.

Abstract

Gastric mucosal cellular DNA content was assessed in patients who had undergone gastric surgery for peptic ulcer disease more than 20 years previously, with the aim of examining the relationship between abnormal DNA content and gastric mucosal dysplasia, as well as determining the effect of different types of surgery on DNA content. Sixty-five subjects underwent upper gastrointestinal endoscopy. In each, six biopsies were taken from the stoma or antrum and graded for severity of dysplasia. Cellular DNA was quantified using a microprocessor-controlled image analysis system with a fast densitometer card on Feulgen-stained slides. DNA histograms were evaluated using the 2c deviation index (2cDI) for proliferative activity and the 4c exceeding rate (4cER) and the 5c exceeding rate (5cER) as indices of malignant potential. In subjects with Billroth II operations, all the above DNA criteria were higher than in Billroth I (P < 0.05), vagotomy and pyloroplasty (P < 0.001), and controls (P < 0.0001). DNA values increased as dysplasia progressed in severity (2cDI, Rs = 0.67; 4cER, Rs = 0.61; 5cER, Rs = 0.72; respectively, P < 0.0001). Among subjects with no dysplasia, more aneuploid cells were found in the Billroth II group, (p < 0.005) compared with the other types of operation. Cellular DNA content is abnormal at an early stage in dysplasia and may even predate it. Increasing values of abnormal DNA content are related to the severity of dysplasia. DNA analysis may be a useful additional tool in surveillance programs to select high-risk patients for screening.