indiacancer.org - Small Bowel Cancers

Small Bowel Cancers

		What is the Small Bowel?
		What is Cancer of the Small Bowel?
		How do Cancers of the Small Bowel present?
		How are Small Bowel Cancers detected?
		What are staging and grading?
		How are Small Bowel Cancers treated?
		What are the side effects of treatment for Small Bowel Cancer?
		What is the importance of follow up?

What is the Small Bowel?

The small bowel or the small intestine is the longest part of the digestive system or the gastrointestinal tract. It is preceded by the stomach and succeeded by the large bowel or the colon. It is encompassed almost entirely under the arch formed by the colon.

The small bowel begins at the pylorus, which is the terminal thickened portion of the stomach. The first part of the small bowel is the duodenum, which is the shortest part of the small bowel and is in the form of a 'C'. It receives the common bile duct and the duct from the pancreas in its second part and terminates into the jejunum, which forms several loops before continuing as the ileum. The ileum ends at the ileocaecal junction which is in the form of a natural one way valve, directing bowel contents from the ileum into the caecum, which is the first part of the large bowel or colon.

The function of the small bowel is almost entirely digestive. Because of its great surface area, it is able to absorb the maximum possible nutrients from the partially digested food passed onto it by the stomach. It also secretes quite a few digestive enzymes.

Digestive System

What is Cancer of the Small Bowel?

Cancer which arises from any part of the small bowel. It may be of several varieties.

Adenocarcinoma arises from the lining cells of the small bowel.

Lymphomas arise from the lymphatic tissue in the small bowel. The lymphatic system is the body's natural immune mechanism, which helps it to resist disease and infection. It consists of a network of thin, transparent pipelines, which, just like blood vessels, traverses the entire tissue system of the body. The vessels of the lymphatic system carry lymph, which is a colorless, watery fluid, containing lymphocytes, which are the body's infection-fighting cells. These pipelines stop at various junctions called lymph nodes and continue from there to various other parts. Lymph nodes are arranged in small groups in the underarms, in the neck, in the back of the abdomen, in the chest, and in the groin.

The other main organs of the lymphatic system, also known as the reticuloendothelial system; comprise the tonsils, the bone marrow, the thymus, and the spleen.

Leimyosarcomas are cancers arising from the smooth muscle layers of the small intestine.

How do Cancers of the Small Bowel present?

	The presentation of small bowel cancers can be vague or catastrophic. Vague symptoms include:
		Cramps or pain in the middle of the abdomen, sometimes moving from one quadrant of the abdomen to the other.
		Unexplained weight loss.
		Blood in the stools.
		A lump in the abdomen.
	Catastrophic symptoms occur if the cancer suddenly obstructs the entire lumen of the small bowel, or by its sheer bulk, loops upon itself and strangulates a segment of the small bowel. The presentation in this case is emergent and the patient may need urgent surgical exploration. There is:
		Severe pain in the abdomen.
		Vomiting.
		Constipation, sometimes absolute.
		A lump in the abdomen.

How are Small Bowel Cancers detected?

If these symptoms are present, the doctor may order a barium series. In this, the patient is given a liquid to drink called barium sulfate and it passes down through the gastrointestinal tract, which makes it easier to visualize under x-ray. When the dye is passing through the esophagus, the investigation is known as a barium swallow. When it passes through the stomach into the first part of the duodenum, this part of the investigation is known as a barium meal and subsequent to this, the passage of the dye in an antegrade manner up to the small bowel end is called the barium meal follow-through.

The barium investigations help in delineating the lining of the gastrointestinal tract and any mucosal lesions can be picked up. The investigation can be further enhanced by using double contrast, in which along with barium, a little air is pushed in, to give a contrast for the mucosal or the small bowel lining pattern to stand out. This makes the investigation more sensitive.

The other significant investigation, which may be done is duodenoscopy, in which the doctor has to directly visualize the condition of the inner layer of the small bowel or the mucosa using a thin fibreoptic, self-illuminated tube called the gastroduodenoscope. This is passed down the oral cavity with the patient being conscious and cooperating with the doctor who is able to find almost all cancers of the duodenum this way.

To make the investigation easier, the doctor usually sprays a local anesthetic onto the back of the wall of the oral cavity. If the doctor sees any lesion, which is abnormal, then he may take a small biopsy out of it. A biopsy is a small piece of representative tissue, which is then sent to the pathologist for examination under the microscope to rule out the presence or absence of a cancer.

What are staging and grading?

These are terms with which you must become familiar, if you are dealing with any form of cancer.

When we stage a cancer, we try to establish carefully, the degree of spread of the cancer and if indeed there is spread, to what extent and involving which organs.

The grading of a cancer is a microscopic issue, in which the pathologist lets you know how aggressive this particular type of cancer is; well differentiated means less aggressive, moderately differentiated intermediately aggressive, and poorly differentiated more aggressive.

Both grading and staging help your clinician to establish the prognosis or how serious your disease is, and what is going to be the likely outcome.

Staging may require additional imaging tests such as CT scan, MRI, sonography, IVU, bone scan, or chest x-ray.

How are Small Bowel Cancers treated?

	A lot depends on the patient's constitution, the grade of his disease and its staging. Patients are usually treated by a team of specialists which utilizes a multipronged approach. This includes an an oncosurgeon and a radiotherapist. The plan of treatment is tailored to fit a patient's requirements. If necessary, chemotherapy may become an add on. Treatment strategies. The best chance for a patient's cure is if the tumor can be removed in total. The oncosurgeon endeavors to remove the offending portion of the small bowel, along with a margin of healthy bowel for added safety, along with the associated lymph nodes to which the tumor cells may drain. Then the remainder of the small bowel is rejoined end to end. This operation is called a resection anastomosis. The alternative local therapy to surgery is radiation therapy. This involves the use of high energy, penetrative rays to destroy cancer cells. It affects cancer cells only in the zone treated. Radiation therapy is also employed for palliation i.e. control of symptoms alone in an advanced cancer. Radiation therapy can also be used in adjunct to surgery or chemotherapy, either before or after. Teletherapy or external radiation is given via a machine remote from the body while brachytherapy or internal radiation is given by implanting a radioactive source within the involved tissues. Patients may or may not require both modalities of radiation. Radiotherapy, after initial planning, usually takes just 5 to 10 minutes per day, 5 days a week for about 6 weeks. This time period is flexible depending upon the modality of radiation used. Besides local therapy, the best attempt to control cancer cells circulating in the body and lodged at places other than the small bowel is by using systemic therapy (therapy which affects the entire systems of the body) which is in the form of injections or oral drugs. This form of treatment is called chemotherapy. This form of treatment is given in a cyclical manner (each set of drugs is repeated usually after every 3-4 weeks. Chemotherapy can also be used in combination with surgery, radiotherapy or both, either before or after. Biological therapy employs Biological Response Modifiers (BRM's), which are substances that use the body's own immune system, either directly or indirectly, to fight cancer or to lessen the side effects of the anti cancer drugs. Some examples of BRM's are interferon-alfa and interleukin-2. Small bowel adenocarcinoma:
		Resection anastomosis.
		Surgery to allow the bowel content to go around the tumor, if the same cannot be removed (bypass surgery).
		Radiation for palliation, i.e., relief of symptoms in an advanced case.
		Radiation along with radiosensitizer drugs (drugs which make the cancer more susceptible to radiation).
		Chemotherapy or biological therapy in advanced cases.
	Small bowel lymphoma
		Resection anastomosis.
		Surgery followed by adjuvant chemotherapy or radiation therapy.
		Chemotherapy with or without radiation.
	Small bowel leiomyosarcoma
		Resection anastomosis 2. 3.
		Surgery to allow the bowel content to go around the tumor, if the same cannot be removed (bypass surgery).
		Chemotherapy or biological therapy in advanced cases.(Experimental only).
		Radiation for palliation, i.e., relief of symptoms in an advanced case.

What are the side effects of treatment for Small Bowel Cancer?

	Unfortunately treatment for cancer does cause damage to the healthy tissues. Please ask the clinician about any possible side effects before any form of treatment commences. The effects of radiation depend upon the dose of radiation, the size of the area radiated, and the number and size of each fraction. The commonest side effect is extreme fatigue. Although bed rest is good, most radiotherapists advise the patient to be as mobile as possible. Another common problem is that of radiation dermatitis in which the skin covering the radiated area becomes red, dry, itchy, and may show signs of scaling off. This will slowly settle down after radiation ceases, but there may be a permanent 'bronzing' of the skin. It is important to note here that this skin problem is associated only with teletherapy or external radiation therapy. Radiation also may cause nausea and vomiting, diarrhea, urinary discomfort. There may also be a fall in the white blood cells, which are needed by humans to fight infection. Usually the radiotherapist can suggest the drugs and diet necessary to alleviate such problems. The various drugs in chemotherapy cause a varied spectrum of side effects. The severity and variability of these symptoms are very individualistic, changing from patient to patient. Some of the common side effects are:
		Skin rashes.
		Loss of hair.
		Diarrhea.
		Vomiting.
		Tingling and numbness in the fingers and toes.
		Hearing loss.
	Most are temporary and recede after therapy is over. Hair growth gradually starts after cessation of chemotherapy. The medical oncologist will usually be able to reduce the severity and spectrum of these side effects. The psychology of the patient is very important during therapy. Better psychologically prepared the patient is, better are his chances of having decreased side effects. The patient should drink large quantities of water while the therapy is in progress, and preferably avoid uncooked or raw food. Water should be filtered or boiled. Any relative or person who has any sort of infection such as common cold should be asked to desist from coming close to the patient. Biological therapy The side effects commonly encountered with this therapy are as follows:
		Low grade fever.
		Rashes and bruises.
		Nausea and vomiting (usually mild).

What is the importance of follow up?

The importance of followup cannot be overemphasized. It is a fatal fallacy to assume on the patient's part that once the primary or the first phase of treatment is over, then he or she is cured. It must be stressed here that cancer has a notorious proclivity of coming back again and again. The only way to fight this is to pick up any problem when it is still early, so that it can be nipped in the bud. And the only way to do this is to follow up when the doctor calls you for the next visit. Each such visit will include a detailed history, a physical examination (including an internal i.e. a rectal or vaginal examination), a chest x-ray, an ultrasonography or a CT scan, and various other blood studies as indicated.