Overview

Duodenal cancer is a malignant tumour arising in the duodenum, the first section of the small intestine. It is one type of small‑intestinal cancer and shares features with cancers of the stomach and colon. For general background on malignancy see cancer overview, and for the small intestine anatomy see small intestine. Duodenal tumours can be adenocarcinomas, neuroendocrine tumours or other histological types; clinical behaviour and treatment depend on the tumour type.

Anatomy and role of the duodenum

The duodenum lies immediately beyond the stomach and connects to the jejunum. It receives acidic stomach contents and mixes them with bile and pancreatic secretions to begin the main phase of digestion. See the organ pages: duodenum, stomach and jejunum. Bile from the liver and gall bladder and enzymes from the pancreas support nutrient breakdown; relevant references are bile, gall bladder and pancreas.

Risk factors and causes

Duodenal cancer is uncommon. Several inherited and acquired conditions increase risk. Important associations include:

  • Inherited polyposis and mismatch‑repair syndromes (familial adenomatous polyposis, Lynch syndrome and related disorders).
  • Specific hereditary syndromes such as Peutz–Jeghers and juvenile polyposis, and syndromes that overlap with skin findings like Muir‑Torre and Gardner syndrome.
  • Chronic inflammatory or malabsorptive conditions such as celiac disease and Crohn's disease in some patients.

Symptoms, detection and diagnosis

Early disease may be asymptomatic or produce vague upper abdominal discomfort. More typical symptoms include unexplained weight loss, persistent abdominal pain, gastrointestinal bleeding, anaemia or an obstructive sensation after eating. Diagnosis relies on endoscopic examination with biopsy and imaging to stage the disease. Common diagnostic steps include upper endoscopy, cross‑sectional imaging and histopathological assessment.

Treatment and prognosis

Treatment depends on tumour type, location and stage. Surgical resection is the principal curative option for localized disease; the extent ranges from local excision to more extensive resections. Chemotherapy and radiation are used in selected situations, and targeted or hormonal therapies may apply for specific histologies. Prognosis varies widely by stage and pathology; early detection generally improves chances for a favourable outcome.

Key distinctions and clinical importance

Duodenal cancer is distinct from gastric and colorectal cancers in frequency, presentation and typical molecular features, though overlaps occur. Because it is rare, patient care often involves multidisciplinary teams and considerations of inherited cancer risk. Patients with syndromic predispositions may undergo surveillance to detect precancerous polyps or early malignancy. For related conditions and comparisons see gastric and colorectal cancer.