What is Small Intestine Cancer?
The small Intestine of an individual is a long coiled tube which is made up of three parts called the duodenum, jejunum, and the ileum which assists in digestion of the nutrients from the food that is eaten and dumps the remaining food into the large intestine or the colon. The food first enters the duodenum where it is broken down with the help of enzymes secreted by the pancreas and bile from the liver. The food then enters the jejunum from where it is pushed to the ileum where further digestion takes place before the food is pushed through to the large intestine. Any tumor in the small intestine may obstruct the passage of food and affect digestion of food. This is what is called as small intestine cancer.
As the tumor gets larger and larger it starts to put pressure on the adjoining organs as well and may start to affect their function. This may result in severe abdominal pain. In some cases of small intestine cancer, the tumor may start bleeding which may result in excessive blood loss resulting in anemia. An individual with small intestine cancer will start having black tarry stools. Once the intestine is completely obstructed, it may result in intense abdominal pain along with nausea and vomiting resulting in the necessity for an emergent surgery for resection the tumor causing small intestine cancer.
What are the Types of Small Intestine Cancer?
Small Intestine Cancers are of numerous types of which the most common type are:
- Adenocarcinomas: This is the most common type of small intestine cancer. This type of cancer develops in the cells that line the walls of the small intestine. This type of cancer usually develops from benign growth on the intestinal walls called polyps.
- Sarcoma: This is a type of small intestine cancer which develops in the connective tissue of the small intestine.
- Carcinoid Tumors: This is a type of Small Intestine Cancer in which the tumors grow from the intestinal lining. These types of tumors grow very slowly and hence the symptoms may not be evident for quite a significant amount of time.
What are the Risk Factors for Small Intestine Cancer?
Some of the risk factors for Small Intestine Cancer are:
- Age: People above the age of 60 are more likely to develop small intestine cancer.
- Gender: Males are likely to develop small intestine cancer more than females
- Genetics: Majority of small intestine cancer has a genetic link to it and hence if an individual has a family history of small intestine cancer then he or she is at an increased risk for developing this condition than the normal population.
- Smoking and tobacco use also increases the risk for an individual developing small intestine cancer
- Eating a diet rich in fats also puts an individual at an increased risk for developing small intestine cancer.
- Exposure to certain chemicals like vinyl chloride and herbicides
- Gastrointestinal conditions like Crohn disease or celiac disease also puts an individual at an increased risk for developing cancer of the small intestine.
What are the Symptoms of Small Intestine Cancer?
Some of the Symptoms of Small Intestine Cancer are:
- Abdominal pain
- Unintentional weight loss
- Excessive fatigue and weakness
- Black tarry stools
- Visible lump in the abdomen
- Severe abdominal pain along with nausea and vomiting.
The symptoms of small intestine cancer resemble that of a variety of other gastrointestinal disorders and hence it is not an easy condition to diagnose first up. Small tumors are completely asymptomatic and hence make the diagnosis that much more difficult. It may take years in cases of slow growing tumors like carcinoid tumors to diagnose small intestine cancer.
How is Small Intestine Cancer Diagnosed?
If small intestine cancer is suspected in an individual then the treating physician will perform a battery of tests in order to confirm the diagnosis. These tests are:
- For almost all the cases, a barium contrast study will be done of the small intestine to see whether there is a presence of a tumor.
- Once a tumor is identified then an Upper GI Endoscopy will be done to located and pinpoint the area of concern in the small intestine
- This will be followed by radiological studies like MRI and CT scan of the abdomen to see the degree of tumor and to what extent it has spread and whether it is compressing the adjoining structures of the body
- A biopsy of the tumor is then taken to confirm the diagnosis of Small Intestine Cancer
How is Small Intestine Cancer Treated?
The front line treatment for small intestine cancer is surgery to remove the tumor in its entirety. This is then followed by radiation and chemotherapy to kill any cancer that may be remaining even after complete resection of the tumor, although radiation and chemotherapy is quite uncommon for small intestine cancer unless the cancer has spread to many areas. A bypass procedure may be performed if the tumor has caused a bowel obstruction.
Prognosis & Survival Rate of Small Intestine Cancer
Unfortunately, the prognosis for small intestine cancer is quite guarded to poor. This again depends on how early the diagnosis is made and treatment is started. For adenocarcinomas of the small intestine the survival rate is only about 15-20%. Individual with this type of cancer have a survival rate of at least five years after successful resection of the tumor and completion of treatment and clinical trials.
However, the survival rates of individuals significantly increase if the cancer is diagnosed while it is still limited to the inner walls of the small intestine and there is no involvement of the lymph nodes. Individuals with carcinoid type small intestine cancer have a better survival rate since these are extremely slow growing tumors and there is a high likelihood of these tumors being diagnosed in the early stages even though such tumors are completely asymptomatic. Unfortunately, the prognosis is quite poor if an individual has Crohn or Celiac Disease and have a weak immune system along with Small Intestine Cancer.