Diagnosis

Small bowel cancer

Etiology

Cause

• Sporadic mutation

• Genetic factors

Histology [3us][z34]

• Adenocarcinoma (35%)

• Neuroendocrine tumor/carcinoid (37%)

• Gastrointestinal stromal tumor (8%)

• Lymphoma (17%)

• Metastasis from melanoma or invasion from the adjacent structures

Localisation [z34]

• Duodenum: 50%

• Jejunum 30%

• Ileum 13%

Risk factors [z34]

• Diet (red meat and smoked or cured foods)

• Chronic inflammatory bowel disease (Crohn disease)

• Malabsorptive immune disorders (celiac sprue)

• Hereditary intestinal disorders (HNPCC, FAP, and Peutz-Jeghers syndrome)

Complications [z34]

• Gastrointestinal bleeding

• Small bowel obstruction

• Small bowel perforation --> peritonitis

Epidemiology

Incidence per 100.000 [kfe][rr1][v3f][gps][nva]

Approach

• Blood test: complete blood cell count, chemistry, liver, chromogranin, serotonin, CA19-9, CEA

• Hemofec

• 24-hour urine 5-HIAA

• Pentagastrin provocation test

• CT abdomen

• MRI

• PET-CT

• Endoscopy:

  • Esophagogastroduodenoscopy

  • Push enteroscopy

  • Double-balloon enteroscopy

  • Wireless video capsule endoscopy (only visualization and no tissue sampling)

  • Endoscopic ultrasound: Diagnostics, stagings, tissue sampling

Treatment

1. Surgical resection and en-bloc lymphadenectomy [q1k][z34]

   • Sarcoma/GIST: No spillage of resected tissue and KIT inhibitors (Imatinib)

   • Adenocarcinoma: Resection, if N+ --> adjuvant chemotherapy

   • Neuroendocrine tumors: Typically well differentiated and indolent, risk of metastasis (adjuvant chemotherapy and liver transplantation)

   • Lymphoma: Surgical resection and adjuvant chemotherapy

   • Additional procedures:

     • Peri-ampullary tumor: Pancreaticoduodenectomy (Whipple)

     • Peritoneal metastasis/carcinomatosis: Metastasectomy, HIPEC

2. If unresectable obstruction:

   • Palliative surgical bypass

   • Palliative radiation therapy

   • Palliative stent placement

3. Chemotherapy: Metastasis or regional lymph node involvement (adjuvant)

   • Capecitabine

   • 5-fluorouracil (5-FU)

   • Oxaliplatin

   • Irinotecan

   • Capecitabine and oxaliplatin (called CAPOX)

   • CAPOX and bevacizumab

   • 5-FU and leucovorin with oxaliplatin (FOLFOX)

   • 5-FU and leucovorin with irinotecan (FOLFIRI)

Differential diagnoses

Acute pancreatitis, Adhesion, Ampullary carcinoma, Appendicitis, Benign bile duct tumor, Benign neoplasm of the small intestine, Carcinoid syndrome, Celiac disease, Cholangiocarcinoma, Choledocholithiasis, Colorectal cancer, Colorectal polyp, Crohn disease, Esophagitis, Gastric cancer, Gastritis, Hemangioma, Infectious colitis, Irritable bowel syndrome, Leiomyosarcoma, Lipoma, Meckels diverticulum, Pancreatic cancer, Pheochromocytoma, Ulcerative colitis, Ulcer disease