Chapter 13: GI Small Intestine Neoplasms Flashcards
Describe adenomas of the small intestine.
Benign tumor, but may undergo malignant transformation (especially villous type).
May be tubular villous, or tubulovillous.
May present with bleeding and intussusception.
A patient with a family history of GI cancer presents with a small intestinal mass as well as mucocutaneous melanin pigmentation on the face, buccal mucosa, hands, feet, and perianal and genital areas.
Patient has symptoms of obstruction and intussusception.
Biopsy looks like below.
Peutz-Jeghers syndrome.
Autosomal dominant inheritance. Inactivating mutations on LKB1 that encodes a protein kinase. Cancers of many organs - breast, lung, pancreas, gonads, and thyroid.
Polyps (see histology) are hamartomas - branching networks of smooth muscles continuous with muscularis mucosae supporting the glandular epithelium of the polyp. Generally benign, 3% of patients develop adenocarcinoma.
A small bowel GI mass presents as an intramural mass covered by intact mucosa.
Gastrointestinal stromal tumor. More likely to be aggressive than gastric counterparts, but rare.
A young male with Crohn disease presents with bloody stool. Endoscopy finds a polypoid mass.
Histology shows that the mass begins in crypt epithelium.
Adenocarcinoma - Crohn disease is a risk factor. Tend to occur near inflammatory lesions (ileum).
Familial adenomatous polyposis, HNPCC syndrome (Lynch syndrome) and celiac disease also risk factors.
Subtypes: Polypoid, ulcerative, annular and stenosing. Can be lead point of intussusception. Begin in crypt epithelium - resemble colorectal cancers.
A patient presents with jaundice. A mass is discovered that involves the papilla of Vater.
Ampullary carcinoma - a subtype of adenocarcinoma.
Obstructive jaundice or pancreatitis.
A type of lymphoma that complicates celiac disease and ulcerative jejunoileitis. Tends to express CD130.
Enteropathy-type intestinal T-cell lymphoma (EITCL).
A young man from India with a history of alpha-heavy chain disease (B lymphocytes secrete heavy chain of IgA without light chains) presents with chronic abdominal pain, diarrhea, and clubbing of fingers.
A diffuse infiltrate of plasmacytoid lymphocytes or plasma cells is seen in the mucosa and submucosa. Additionally, mucosal atrophy and malabsorption are noted.
Mediterranean-type Intestinal Lymphoma.
A 50-year-old man presents with abdominal pain, diarrhea, and clubbing of fingers. A fungating mass is found in the ileum. A clonal expansion of lymphocytes is found.
Western-type intestinal lymphoma.
Fungating mass OR elevated ulcerated lesion OR diffuse segmental thicking of bowel wall OR plaque-like mucosal nodules.
Intussusception, intestinal obstruction, perforation are important complications.
A patient presents with diarrhea, episodic flushing, bronchospasm, cyanosis, telangiectasia, and skin lesions.
Examination also reveals right-sided cardiac valvular disease.
Histology shows cords of uniform small, round cells.
Neuroendocrine tumors (Carcinoid tumors). Malignant with low metastatic potential. MEN1 syndrome.
Can cause peritoneal adhesions/kinking of the bowel with possible intestinal obstruction.
Description to the right is carcinoid syndrome. Small percentage of NETs. Serotonin metabolized into 5-HIAA, seen in urine. Causes endocardial fibrosis. Pulmonic stenosis and tricuspid regurgitation.
A child presents with gas cysts.
Pneumatosis cystoides intestinalis.
Usually underlying GI disease - obstruction, peptic ulcer, Crohn, mesenteric ischemia, volvulus, neonatal necrotizing enterocolitis. COPD, mechanical ventilation.
Mechanical break in mucosal continuity allows air from lumen to enter submucosa.
