Objective:

To highlight the diagnostic challenges of metastatic pancreatic ductal adenocarcinoma (PDAC) that can be masked by benign-appearing gastroduodenal ulcers, emphasizing the need for thorough investigation.

Approach:

• Case Presentation: A 69-year-old man presented with intermittent epigastric discomfort for 1 month. Upper gastrointestinal endoscopy revealed multiple ulcerative lesions involving the esophagus, stomach, and duodenum. Initial biopsies showed chronic inflammation without malignancy, and Helicobacter pylori testing was negative.
• Management: The patient was treated with high-dose vonoprazan (20 mg, bid, p.o.), leading to apparent healing of the ulcers. However, persistent symptoms and rising CA19-9 levels prompted further imaging.
• Diagnosis: Cross-sectional imaging revealed a pancreatic mass with metastases, and a laparoscopic biopsy confirmed moderately differentiated adenocarcinoma, establishing a diagnosis of metastatic PDAC.

Key Findings:

• Apparent endoscopic healing of gastroduodenal ulcers does not rule out underlying malignancy.
• Persistent symptoms and rising CA19-9 levels necessitate further investigation despite initial benign findings.

Interpretation:

This case highlights the importance of considering underlying malignancies in patients with multifocal ulcerative disease, even when initial evaluations appear benign.

Limitations:

• The case is based on a single patient, limiting generalizability.
• Potential confounding factors in the patient's history and presentation were not fully explored.

Conclusion:

Timely pancreatic imaging should be considered in cases of unresolved ulcerative disease with persistent symptoms and elevated tumor markers.