Primary Duodenal Adenocarcinoma: Uncommon Tumor, Uncommon Presentation. A Case Report and Review of the Literature

INTRODUCTION: The symptoms of primary duodenal adenocarcinoma, which is a rare but aggressive tumor, are vague and nonspecific and often result in a delayed diagnosis or misdiagnosis. This results in a tumor being diagnosed at an advanced stage when it becomes unresectable secondary to local and distant spread. CASE PRESENTATION: A 64-year-old Nepalese female presented to our hospital with epigastric pain, anorexia, and significant weight loss that developed over two-and-a-half months. Upper gastrointestinal endoscopy showed an ulceroproliferative growth in the first part of the duodenum with no features of duodenal stenosis. Contrast-enhanced computed tomography of the abdomen revealed heterogeneously enhancing, circumferential, asymmetrical thickening in the first part of the duodenum and multiple liver metastases. Biopsy of the mass revealed features suggestive of moderately differentiated adenocarcinoma of the duodenum. She was managed with palliative care during her hospital stay. The unique presentation in our case was that the tumor did not cause stenosis and the patient could consume food till the last day of her life. CONCLUSION: In patients with primary duodenal adenocarcinoma, the non-stenotic lesion is also a possibility. Clinicians should always maintain a high degree of suspicion to avoid the delay in diagnosis or misdiagnosis.