Abstract:

Objective To evaluate the diagnostic performance of adopting serum pepsinogenⅠ(PGⅠ)，pepsinogenⅡ (PG Ⅱ), and the ratio of PGⅠ and PGⅡ (PGR) as indexes for screening the chronic atrophic gastritis and precursor lesions of gastric cancer. Methods A total of 474 patients who were diagnosed with diseases other than gastric cancer by the gastroscope were selected and divided into the minor non-atrophic gastritis group (control group, n=164), chronic atrophic gastritis group (n=162), and chronic atrophic gastritis with intestinal metaplasia group (n=148). Serum PG Ⅰ and PG Ⅱ levels were quantitatively measured by the latexenhanced immunoturbidimetric method and the PGR was calculated. The diagnostic performance of PGⅠ, PGⅡ, and PGR was evaluated by the receiver operator characteristic (ROC) curve. Results Compared with the control group, PGⅠ level, PGⅡ level, and PGR of the chronic atrophic gastritis group and chronic atrophic gastritis with intestinal metaplasia group decreased significantly (P<0.01). Values of the area under the ROC (AUC_ROC) of PGⅠ, PG Ⅱ, and PGR for diagnose of chronic atrophic gastritis were 0.679, 0.593, and 0.622; the best cutoff values were 71.8, 9.1, and 8.12; the values of sensitivity were 66.1%, 54.3%, and 77.2%; and the values of specificity were 61.0%, 61.6% and, 43.9%. Values of AUC_ROC of PGⅠ, PGⅡ, and PGR for diagnosis of atrophic gastritis with intestinal metaplasia were 0.787, 0.583, and 0.836; the best cut-off values were 59.4, 9.8, and 6.76; the values of sensitivity were 64.9%, 58.8%, and 81.8%; and the values of specificity were 78.1%, 55.5% and 77.4%. The values of parallel combined sensitivity and specificity of PGⅠ and PGR were 93.6% and 60.4%, while the values of series combined sensitivity and specificity of PGⅠ and PGR were 53% and 95%. Conclusion Combined use of PGⅠ level and PGR as indexes for monitoring the status of gastric mucosa can improve the diagnostic performance. It is an indication of atrophic gastritis with intestinal metaplasia if PGⅠ level and PGR are both smaller than the best cut-off values.

Key words: pepsinogenⅠ, pepsinogenⅡ, pepsinogen ratio, sensitivity, specificity, receiver operator characteristic curve