It is one of the rarest types of cancer affecting the gastrointestinal tract. It happens when malignant cells form in the small intestine, or small bowel.

Statistics:

• About 65% of people diagnosed with early-stage adenocarcinomas are alive five years later.
• The survival rate in later stages is much less at 4%.
• Early-stage carcinoid tumors have a five-year survival rate of 95%, while later-stage cancers have a survival rate of 42%.
• Small intestine cancer is quite rare, accounting for only about 3% of the total cases recorded per year. It is rare in India, though there's evidence of a rising trend similar to global patterns in other parts of the world.

Location:

The small intestine is part of the body’s digestive system, and a part of the gastrointestinal (GI) tract. It connects the stomach to the large intestine and lies in the abdominal cavity. The small intestine consists of three parts- the duodenum, jejunum, and ileum. Most small intestine cancers form in either the duodenum or the ileum.

TYPES OF SMALL INTESTINE CANCER:

• Carcinoid tumors: It starts in the neuroendocrine cells, which help the body produce hormones and control the release of digestive juices in the small intestine. A little less than half of small intestine cancer cases involve carcinoid tumors.
• Adenocarcinoma: it starts in the glandular epithelial cells in the lining of the small intestine. Adenocarcinomas constitute about one-third of the total reported small intestine cancer cases.
• Sarcoma: It starts in connective tissues like cartilages or muscles. The most common type of sarcoma in the small intestine is called a Gastrointestinal Stromal Tumor (GIST).
• Lymphoma: It starts in cells called lymphocytes, found in the lymphatic system.

Stages:

Small intestine cancer stages range from I (1) to IV (4). The lower the number, the lesser the cancer has spread.

Information used to determine the stage:

• Size of the tumor (T): how large is the cancer? Is it contained inside the small intestine? Has it grown into other organs too?
  • Metastasis (M): Has the cancer spread to distant lymph nodes or organs?
• Spread of nearby lymph nodes (N): Has the cancer spread to the nearby lymph nodes?

SYMPTOMS:

• Abdominal pain or cramps.
• A lump or unusual bulge in the abdomen.
• Nausea, vomiting and diarrhea.
• Unexplained weight loss.
• Anemia.
• Jaundice.
• Bloody stool (dark red or black).
• Flushed skin (especially purplish coloring) on the arms and upper body.

Risk Factors:

• Age: Cancer risk for many types of small intestine tumors increases with age. The average age of diagnosis is 65.
• Sex: Small intestine cancer is slightly more common in males.
• Inherited genetic conditions: Having a biological parent, sibling or child with certain conditions may increase the risk. These conditions include familial adenomatous polyposis (FAP), Peutz-Jeghers syndrome, hereditary nonpolyposis colorectal cancer (HNPCC) and Lynch Syndrome.
• Inflammatory conditions: Diseases involving chronic inflammation affecting your bowels, like Crohn’s disease and celiac disease, may increase your risk.
• Autoimmune disorders or a weakened immune system: Conditions that weaken your immune system, like HIV/AIDS, Crohn’s disease and celiac disease, may increase your risk. Treatments like radiation therapy may weaken your immune system and make you more susceptible to small intestine cancer. Drugs that suppress your immune system following an organ transplant may also increase your risk.
• Some studies have suggested that diet (eating salty or smoked foods and red meat), tobacco use and alcohol consumption may play a role in small intestine cancer risk.

Diagnosis:

• Blood tests:
  • Blood chemistry studies: A test that measures the amounts of certain substances released into your blood by organs and tissues. An unusual (higher or lower than typical) amount of a substance can be a sign of disease in the organ or tissue that produces it. For instance, your healthcare provider may order a liver function test to check for signs that cancer has spread to your liver.
  • Complete Blood Count (CBC): A test that gives your healthcare provider information about your blood cells. Small intestine tumors may cause bleeding that can reduce your red blood cell count and cause anemia.
• Imaging:
  • Endoscopy: A procedure that uses a thin, tube-like instrument with a light and lens (endoscope) to look inside parts of your gastrointestinal (GI) tract. With an upper endoscopy, your healthcare provider inserts the endoscope into your mouth and uses it to examine your esophagus, stomach and the first part of your intestine near your stomach (duodenum). A double-balloon enteroscopy uses a special endoscope to see deeper inside of your small intestine. During an endoscopy, your healthcare provider may remove tissue samples (biopsy) that can be examined under a microscope for signs of disease.
  • Capsule (pill) endoscopy: A procedure involving swallowing a capsule containing a tiny camera. As the capsule travels through your body, it takes pictures of your GI tract that can be downloaded to a computer for your healthcare provider to view. The name can be a bit confusing, but this procedure doesn’t involve using an endoscope.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside of your body, taken from different angles. A computer linked to an X-ray machine displays the images. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves and a computer to make a series of detailed pictures of areas inside of your body. An MRI and CT scan both provide similar information about how a tumor may be impacting soft tissue. Still, CT scans are used more often to diagnose small intestine cancer.
  • Abdominal X-ray: An X-ray of the organs in your abdomen. An X-ray is an energy beam that can travel through your body and onto film, making a picture of areas inside of your body.
  • Barium X-ray: A procedure that involves coating your GI tract with a chalky substance called barium. The barium makes it easier to see your GI tract on an X-ray. An upper GI series with a small bowel follow-through takes a series of X-rays as the barium travels through your GI tract (esophagus, stomach and small bowel). A lower GI series (barium enema) involves inserting a liquid with barium into your rectum. The barium coats the lower GI tract as X-rays are taken.

Treatment:

• Surgery
  • Resection: Surgery to remove all or part of an organ that contains cancer. Healthcare providers may remove segments of the small intestine and nearby organs (in case the cancer has spread). Afterward, they may perform an anastomosis (joining the cut ends of the intestine together). Healthcare providers may remove lymph nodes near the small intestine to test them for signs of cancer spread.
  • Bypass: Surgery to allow food in the small intestine to go around (bypass) a tumor that is blocking the intestine, but can’t be removed.
• Chemotherapy: uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Depending on the chemotherapy treatment, the drugs may target cancer cells in a specific part of the body (regional chemotherapy) or destroy cancer cells throughout,f. Sometimes, radiation is administered alongside chemotherapy (chemoradiation therapy) after surgery to kill any remaining cancer cells.
  • Chemotherapy after surgery may sometimes be prescribed to kill any remaining cancer cells (adjuvant therapy). Systemic chemotherapy may also be given if the cancer has metastasized.
• Radiation therapy: uses high-energy X-rays or other types of radiation to kill cancer cells or keep them from growing. Healthcare providers may recommend radiation if the cancer can’t be removed surgically. Radiation therapy may also be a part of palliative care to help with symptom relief. Sometimes, radiation is administered alongside chemotherapy (chemoradiation therapy) after surgery to kill any remaining cancer cells.
• Somatostatin analogs: Healthcare providers may recommend somatostatin analogs to treat carcinoid tumors of the small intestine. These medications stop the body from making too many hormones. In turn, they can ease symptoms and help control disease. Examples of somatostatin analogs include lanreotide and octreotide.
  • More research is needed to understand the benefits of using radiation with chemotherapy following surgery for small intestine cancer.
• Targeted therapy: identify weaknesses in cancer cells and use these weaknesses to destroy them. Researchers are currently studying targeted therapy treatments that may aid in treating adenocarcinomas, GIST and lymphomas.
• Immunotherapy: boosts the immune system so it’s better able to fight cancer cells. The immune system naturally fights abnormal cells and dangerous bodily invaders like germs. Unfortunately, cancer cells can sometimes get past the immune system’s defenses. Immunotherapy makes it easier for the immune system to recognize cancer cells and destroy them.
  • Depending on the type of gene mutations inside a tumor, immunotherapy may be recommended.

Prevention:

• Avoiding tobacco and alcohol: Not smoking or using tobacco products and limiting alcohol intake, as they can increase the risk of many cancers, including small intestine cancer.
• Being physically active: Exercising regularly to maintain overall health and support a healthy immune system.
• Eating a balanced diet: Eating a diet rich in fruits, vegetables, whole grains, and lean proteins. These foods provide essential nutrients and antioxidants that can help protect cells from damage. Also, reducing intake of red and processed meats can lower the risk of developing various types of cancer, including small intestine cancer.
• Getting regular medical check-ups: While there are no standard screening tests for small intestine cancer, regular check-ups can help detect any abnormalities early. An individual with a family history of cancer ought to consider genetic counseling and testing to understand the risk and take appropriate preventive measures.
• Maintain a healthy weight: Being overweight or obese can increase the risk of cancer.

Side effects:

• Anemia
• Appetite loss
• Bleeding and bruising
• Constipation
• Diarrhea
• Fatigue
• Fertility Issues
• Hair loss
• Lymphedema
• Memory or concentration problems
• Mouth sores
• Nausea and vomiting
• Nerve issues (peripheral neuropathy)
• Pain
• Skin and nail changes
• Sleep problems
• Urinary problems