PG I and PG II show unique value in diagnosing postoperative biochemical recurrence in patients with gastric cancer after total gastrectomy

Abstract

Objective To investigate the potential of group I pepsinogen (PG I) and group II pepsinogen (PG II) as diagnostic markers for recurrence in gastric cancer (GC) patients post-total gastrectomy. Methods Ninety-six patients who underwent total gastrectomy for GC between June 2022 and June 2023 were included in this study. Clinical data, serum samples, and ascites samples were collected. Patients were categorized based on recurrence status at the time of sample collection and the primary tumor site. PG I and PG II levels were determined using a chemiluminescent immunoassay, and their clinical utility following total gastrectomy for GC was evaluated via receiver operating characteristic (ROC) curve analysis. Results This study included 96 GC patients who underwent total gastrectomy, 55 of whom experienced postoperative recurrence (57.29%). The levels of serum PG I (27.86 (27.04, 30.97) vs. 26.05 (24.16, 27.09) ng/mL; P < 0.0001) and PG II (1.95 (1.23, 3.05) vs. 0.63 (0.47, 0.90) ng/mL; P < 0.0001) were significantly greater in the recurrent group compared to the non-recurrent group. The secretion of PG I and/or PG II by metastatic cancer cells correlated with the primary lesion site. When the cut-off value for serum PG I was 26.93 ng/mL, the area under the curve (AUC) for PG I was 0.77. When the cut-off value for serum PG II was 0.96 ng/mL, the AUC reached 0.90. The combined AUC was 0.97. Conclusion These findings suggest that serum PG I and PG II are valuable biomarkers for identifying GC patients with biochemical recurrence post-total gastrectomy.