Implications of Serum Pepsinogen I in Early Endoscopic Diagnosis of Gastric Cancer and Dysplasia

Abstract

The risk of gastric cancer (GCA) is increased in atrophic gastritis. A low serum pepsinogen group I (SPGI) level is a good serologic indicator of atrophic gastritis of the gastric corpus and fundus, and can be used for diagnosis of subjects with atrophic gastritis and of increased risk for GCA. The present study was undertaken to investigate whether SPGI assay and a diagnostic gastroscopy could enable the diagnosis of GCA at an early stage. The study was carried out as part of the Alpha-Tocopherol, Beta-Carotene Cancer prevention study (ATBC study) in Finland, in which 22,436 male smokers aged 50-69 years were screened by SPGI. Low SPGI levels (< 25 microg/l) were found in 2196 (9.8%) men. Upper GI endoscopy (gastroscopy) was performed in 1344 men (61%) and 78% of these had moderate or severe atrophic corpus gastritis in endoscopic biopsies. A control series of 136 men from the ATBC study cohort with abdominal symptoms, but with SPGI > or = 50 microg/l were similarly endoscopied, and 2.2% of these had corpus atrophy. Neoplastic alterations were found in 63 (4.7%; 95% CI: 3.6%-5.8%) of the 1344 endoscopied men with low SPGI levels. Of these, 42 were definite dysplasias of low grade, 7 dysplasias of high grade, 11 invasive carcinomas, of which 7 were 'early' cancers, and 3 carcinoid tumors. In the control series, 1 man (0.7%) of the 136 men had a definite low-grade dysplasia. Thus, 18 (1.3%; 95% CI 0.7%-2.0%) cases with 'severe' neoplastic lesions (4 advanced cancers, 7 early cancers and 7 dysplasias of high grade) were found in the low SPGI group, but there were none in the control group. All four patients with advanced cancer died from the malignancy within 5 years (mean survival time 2.5 years), whereas surgical treatment in all those with early cancer or high-grade dysplasia was curative. One of the seven patients with early cancer and two of the seven with high-grade dysplasia died within 5 years, but none died from the gastric cancer. Thus, curative treatment was given to 14 of 18 men in whom a malignant lesion was found in gastroscopy. This is about 15% of all gastric cancer cases (92 cases) which were diagnosed within 5 years after SPGI screening in the 22,436 men. Among the gastric cancer cases of the main ATBC study, the 5-year survival rate was 33% (85% of the non-survivors died from gastric cancer). We conclude that assay of SPGI followed by endoscopy is an approach which can enable the early diagnosis of gastric cancer at a curable stage.