Small intestine cancer- adult

December 31, 2014

Synonyms

Overview

The small intestine, or small bowel, lies between the stomach and the colon. The small intestine is about 6 m (20 ft) long. Its primary function is to digest and absorb nutrients. The small intestine makes up more than 70% of the length and 90% of the surface area of the gastrointestinal (GI) tract. The most common cancerous (malignant) tumors of the small bowel include adenocarcinoma, lymphoma, sarcoma, and carcinoids. * In industrialized countries, adenocarcinomas occur most often. * In developing countries, lymphomas are much more common. * All these tumors have the potential to invade the bowel wall, spread into adjoining lymph nodes, and move to distant organs (metastasize).

Symptoms

* Like most GI cancers, early symptoms of small bowel cancer tend to be vague and nonspecific. They may include abdominal discomfort associated with the following: - Nausea - Bloating - Loss of appetite * The following symptoms may indicate advanced disease and should be signs to seek medical attention: - Fatigue - Weight loss - Iron deficiency anemia - Visible blood loss: Blood or a material that looks like coffee grounds may be vomited, or black stools may be passed. - Severe nausea and vomiting because of a blockage in the small bowel by the enlarging cancer: Doctors frequently diagnose small intestine cancer during surgery for unexplained bowel obstruction. - Jaundice (yellowish skin): This is a symptom in people with cancer that involves the upper small intestine because of blockage of the bile ducts draining the liver.

Prevention

The association of small bowel cancer with underlying conditions makes it possible to identify populations at risk and to develop screening programs. * People with a family history of polyp syndromes, such as Peutz-Jeghers and Gardner syndrome, may benefit from regular screening using upper GI tract barium studies. * People with celiac disease are at higher risk of developing both adenocarcinoma and lymphoma of the small bowel. They need to maintain a gluten-free diet. * People with celiac disease who also have new onset weight loss, diarrhea, or abdominal pain need immediate medical attention, including possible CT scan of the abdomen and barium study of the small bowel to rule out cancer. * People with Crohn disease and small bowel bypass procedures also require immediate attention. * Crohn disease -related adenocarcinoma frequently develops in the lower end of the small bowel, making colonoscopy a potentially useful screening tool.

Diagnosis

* In almost all cases, doctors first choose to perform a barium contrast study of the small intestine. * Upper GI tract endoscopy may be useful in detecting areas of concern in the immediate upper GI tract. * A CT scan of the abdomen or an abdominal ultrasound may help to visualize bulky tumors and to rule out any spread of the cancer to adjacent lymph nodes and distant organs such as the liver. * Colonoscopy may help diagnose tumors involving the lower areas of the small bowel.

Prognosis

* Fewer than 35% of people who have adenocarcinoma of the small bowel live past 5 years. * The survival chances are better if the cancer is limited to the inner walls of the small intestine and the lymph nodes are not involved. * The chance of recovery is better still in people who have a carcinoid tumor and lymphoma of the small bowel. These malignancies tend to respond better to chemotherapy and radiation treatment when doctors cannot completely remove the tumor. * The prognosis is poor, however, if a person has a small bowel lymphoma underlying celiac disease or if the person's immune system is weakened.