Cancer is a group of diseases that start when cells in the body start to grow out of control. When this abnormal growth of cells occurs to the gallbladder it is called gallbladder cancer. This type of cancer is very rare in Tanzania while number of women being slightly higher compared to that of men. To understand better about gallbladder cancer it is important for one to know a little bit about gallbladder and its functions.
Colorectal cancer is the disease that start when cells in the rectum or colon change and start growing out of control. This out of control growth will result into development of mass called tumor. Tumor can either be benign or malignant. Benign tumor is the one that is enclosed in one area and cannot spread to other parts of the body. Malignant tumor is the one that is not enclosed and can spread to other parts of the body. Malignant tumor is also called cancer. Colorectal cancer is sometimes called bowel cancer.
About colon and Rectum,
Colon and rectum are the parts of the digestive tract (gastrointestinal tract) making up the large intestine. Large intestine is divided into main five sections, ascending colon, transverse colon, descending colon, sigmoid colon and rectum. During the digestion process, small intestine will empty its content into the caecum from which the contents will enter the ascending part of the colon which takes the contents into transverse part then descending part, sigmoid section and finally into the rectum. While inside the colon, water and electrolytes are absorbed from the digestion contents and the remaining are waste matters that will be temporally stored in the rectum before removal from the body through anus.
Colorectal cancer develop from the mucosa of the bowel (inner lining). It normally starts as small growths on the intestinal wall called polyps. Most of those growths (polyps) are harmless (benign), but over a certain period some become cancerous (malignant). There are several forms of polyps including adenomatous polyps and hyperplastic polyps.
Types of colorectal cancer1. Adenocarcinoma. Adenocarcinoma develop from mucus producing cells of the colon and rectum. This is the most common type of colorectal cancer in Tanzania. 2. Carcinoid tumors. These develop from hormone producing cells. 3. Lymphomas. 4. Sarcomas 5. Gastrointestinal stromal tumors.
Risk factors of colorectal cancerWhen dealing with cancer, anything that increases your probability of developing cancer is called a risk factor. Risk factors only influence development of cancer but it does not directly cause cancer. Sometimes people with risk factors do not develop the disease while those with no risk factors do develop the disease. Knowing risk factors will help you live your life making some better healthy choices to reduce the risk. The risk factors of colorectal cancer include the following.
1. Age. Colorectal cancer is common among older people. Statistics indicate that, those the disease is more common among those with 50 years and above.
2. Family history of the disease. Statistics indicate that, some cases of colorectal cancer run in families with strong history of the disease.
3. Gender. Statistically, men are said to be at slightly increased risk of developing the disease compared to women.
4. Personal history of the disease or polyps. Those with the history of having colorectal cancer or adenomatous polyps at some point in their life are said to be at increased risk of developing colorectal cancer than those with no such history.
5. Rare inherited genetic conditions. Some inherited genetic conditions tend to increase chances of developing colorectal cancer at some point in life. These conditions include, Familial adenomatous polyposis (FAP), Lynch syndrome (hereditary nonpolyposis colorectal cancer (HNPCC)),MYH-associated polyposis (MAP), juvenile polyposis syndrome (JPS), Gardner syndrome and Peutz-Jeghers syndrome (PJS).
6. Life style factors. Being overweight, having a diet high in red meat,drinking alcohol and smokingwill increase chances of developing colorectal cancer.
7. Inflammatory bowel disease. Those with inflammatory bowel disease (IBD), such as ulcerative colitis or Crohn’s disease, may develop chronic inflammation of the large intestine which tend to increase chances of colorectal cancer.
Prevention of colorectal cancer
To prevent something you need first to know what causes it. Since the specific cause of colorectal cancer is still unknown, currently there is no proven way of completely preventing development of colorectal cancer but there are some ways that may help reduce chances of developing it. These include the following;
a) Screening tests. Regular screening tests for those at risk of developing colorectal cancer (average and high risk) will help detect any conditions with potential of developing into colorectal cancer before cancer develop. This include detecting polyps before changing into colorectal cancer which normally takes years to change into colorectal cancer.
b) Physical activities. Physical exercises help to reduce excess fat in the body which will reduce your chances of developing colorectal cancer.
c) Diet. Taking diet with more fruits, vegetables and low in red(processed) meat will help to lower your chances of developing colorectal cancer.
d) Alcohol drinking and smoking. Cigarette smoking and excess alcohol drinking are said to increase your chance for colorectal cancer, so by avoiding such life style, it will help to reduce that chance.
e) Non-steroid anti-inflammatory drugs (NSAID). For those at high risk of developing colorectal cancer such as those with history of the disease or polyps, some studies suggest that aspirin and other NSAIDs may help to reduce the risk to develop colorectal cancer. However, regular use of NSAIDs may cause major side effects, including bleedingfrom stomach irritation or stomach which may outweigh benefits to those at average risk. It is important to also know that, using aspirin or other NSAIDs it does not exclude you from having regular screening tests
Early detection and screening of colorectal cancer
When it comes to cancer, early detection normally provide better treatment outcome. If colorectal cancer is found early, chances for better treatment outcome are very high. For most cancers, early detection has been greatly contributed by the presence of screening processes.
Screening is the process of running some tests to someone with no symptoms of the disease with the intention of determining presence or absence of the disease. Screening tests are normally done on regular basis to those at risk of the disease including age factor. Whether a person should start screening tests earlier or should have the tests more often, will depend on the level colorectal cancer risk that person is in.
For those at higher risk of developing colorectal cancer like those with the personal or family history of the disease or polyps, screening tests will be done more often than those with no history. Screening tests for this disease include the following;
==> Colonoscopy. Colonoscopy involve using a flexible, lighted tube which is inserted into the rectum and entire colon to look for polyps or cancer. During the process, the patient will be under anesthesia (sedated). Sometimes the doctor may take a tissue sample for biopsy during the test.
==> Sigmoidoscopy. Involve using a flexible, lighted tube which is inserted into the rectum and lower colon to check for polyps, cancer and other abnormalities. With this test, the doctor cannot check for abnormalities in the upper part of colon and other parts such as transverse and ascending colon. During the test, the doctor can also take tissue sample for more examination in the laboratory.
==> Fecal occult blood test (FOBT) and fecal immunochemical test (FIT). These two tests are used to look for hidden (occult) blood in stool. FOBT is done through normal chemical reaction, while fecal immunochemical test (FIT) also known as immunochemical fecal occult blood test (iFOBT) is done through chemical reaction with human hemoglobin protein found in red blood cells.
==> Double contrast barium enema (DCBE). This involve the use of x-rays. It is also known as barium enema with air contrast. During the test, barium sulfate and air are put into the colon and rectum through the anus so as to outline their inner lining when x-ray picture is taken. If the test shows any abnormalities, more tests will be done.
Signs and symptoms of colorectal cancerPeople with colorectal cancer tend to experience some of the following symptoms. Sometimes those signs and symptoms may be as the result of other medical conditions that are different from cancer. Therefore, going to see a doctor upon experiencing any of the symptoms is advised.Some of those signs and symptoms includes the following;
a) Blood in the stools or feces
b) Change in bowel habit such as diarrhea and constipation
c) Discomfort in the abdomen, including frequent bloating, gas pains, fullness, and cramps
d) Feeling that the bowel hasn’t emptied completely aftera bowel movement
e) Weakness or fatigue
f) Rectal or anal pain
g) Abdominal pain or swelling
h) Lumps in the anus and rectum
i) Unexplained weight loss
j) Unexplained iron-deficiency anemia.
Diagnosis of colorectal cancerMedical diagnosis simply means identification of nature of an illness by elimination of the symptoms. Normally people don`t go to hospital knowing they have cancer but during diagnostic procedures is when doctors detect the disease.
Following suspicion of the disease, doctors normally run combination of tests to determine whether there are cancerous cells in the body or not and if there are cancer cells, how far have they spread. Along with thorough medical history and physical examination, doctors normally use combination of the following tests to diagnose cancer.
1. Laboratory tests. Laboratory tests are important in ruling out other conditions and confirming diagnosis. For cancer diagnosis laboratory tests normally include blood tests, urine tests, tumor markers and other body fluids tests.
2. Blood tests. Blood tests help to reveal level of different substances in the blood which will help doctors to know if there is anything wrong in the body. From blood tests doctors can see complete blood count which indicates number, size and maturity of blood cells. Also from the blood tests doctors can analyze if kidney and liver are working properly.
3. Urine tests. Urine tests (urinalysis) involve laboratory examination of urine to check presence of blood, proteins, and other substances such as drugs. For instance blood in the urine may be an indication of benign condition, infection or other health problem.
4. Tumor markers. These are biomarkers (proteins) that can be produced by both cancer cells and normal body cells in response to cancer. Tumor markers are released into the blood or urine. Although studies are still conducted to determine role of these markers in diagnosing cancer because sometimes people with benign condition will have elevated level of these proteins. Also not all tumors have their markers and some markers are not specific to one type of tumor.
5. Other body fluids. Despite being rarely used, sometimes body fluids can be tested in the lab during diagnosis of cancer. For instance the use of cerebral spinal fluid (CSF) and pleural fluid. CSF is used in diagnosis of brain tumors while pleural fluid for lung cancer.
6. Diagnostic imaging. Diagnostic imagings involve tests that create pictures of inside the body that help the doctor to see if there is tumor or not. There are several imaging tests used in cancer diagnosis depending on the type and location of cancer suspected. These imaging tests include;
7. Computed tomography (CT) scan. CT scan machine is a donut-shaped scanner that uses x-rays to create series of pictures of body organs from different angles. This machine is linked to a computer where those series of pictures taken will be combined to create a 3D- image of inside the body. During the scanning process patient will lie still on the table which will slide into the scanner. In order to get a clear image, sometimes the doctor will inject the patient with a contrast material before scanning. From the images the doctor will be able to differentiate between healthy and unhealthy tissues.
8. Magnetic resonance imaging (MRI). MRI is an imaging technique that uses powerful magnet and radio waves to take series of pictures of body organs and create a 3D image in a computer linked to a machine. Just like in CT, during MRI procedure the patient will lie on a table that will slide into a long round chamber. Also during this procedure the doctor may inject the patient with a contrast material for clear image view.
9. X-ray. This is an imaging technique that is uses low dose of radiation to create pictures of inside your body. Technician will position the patient and direct the x-ray beam to the intended part of the body.
10. Ultrasound. Ultrasound is a diagnostic imaging procedure that uses high energy sound waves to produce images of organs inside the body. During the examination, a patient will lie on the table while the technician will slowly move a device called transducer on the skin over the part of the body that is being examined.
11. PET scan. Positron emission tomography (PET) scan is an imaging test that uses radioactive glucose to create 3-D images of areas inside the body. Radioactive glucose is used for this test because cancer cells tend to absorb more glucose than normal body cells, so the scan will show which areas of the body has more glucose than others. Before the scan, doctor will inject the patient with tracer called radioactive glucose then during imaging the patient will be asked to lie on the table that will be moving back and forth through the scanner.
12. Bone scan. Bone scan is used to examine bones. When it comes to cancer, bone scan is used for diagnosis of bone cancer or cancer that has metastasized into the bones. Before the test, patient will be injected with small amount of radioactive material that tends to collect more on abnormal parts of the bones. Then pictures that will be taken by a scan will indicate the distribution of those radioactive materials in the bones throughout the body.
13. Biopsy. Biopsy is a diagnostic procedure that involves removing a tissue sample from the body and examines it under microscope in the laboratory. Examination in the laboratory is normally done by a pathologist who will check if the cells in the tissue are cancerous or not. In most cancer cases, biopsy is considered to be the confirmatory test. Depending on the location and type of cancer, biopsy can be obtained in different ways. Some of them include;
==> Using needle. By using a thin needle, doctors can draw same tissue or fluid for examination under microscope. This method can be used to draw some fluid (spinal tap), bone marrow (bone marrow aspiration), blood or small amount of tumor from the suspected organ such as liver and breast (fine needle aspiration).
==> Surgery. Abnormal tissue samples are obtained while the doctor is performing the surgery. Tissues are then sent to the lab for examination during the surgery. If the surgeon removes just a portion of abnormal area it is called incisional biopsy while when the entire tumor (abnormal site) is removed it is called excisional biopsy.
==> Using endoscope. Endoscope is a thin, lighted tube with a camera (focusing telescope) at the end. It is used for viewing inside the body through natural openings like mouth and anus. During an examination if the doctor sees any abnormal tissue, then endoscope can also be used to take sample for that tissue. There are different kinds of endoscopy exams depending on the site of the body being examined. Some of the exams include colonoscopy (for rectum and colon), bronchoscopy (for trachea, bronchi and lungs) and esophagogastroduodenoscopy EGD (for esophagus, stomach and duodenum)
NB: In addition to medical history and physical examination, diagnosis of colorectal cancer involves the use of colonoscopy, biopsy, blood tests, sigmoidoscopy and other imaging tests like CT scan, MRI, X- ray and PET scan.
Treatment of colorectal cancerFollowing cancer diagnosis, the doctor will break the news and it is normally not very easy to accept that it is cancer. The doctor will be there to help the patient process the news and to help the patient in taking the next steps.
After the patient receives and processes the news that he/she has cancer, one of the most important steps that will follow is decision making. The doctor will present to the patient (relatives/parents/guardians) with all the possible treatment options and explain what they mean. Then with the help of the doctor, the patient (relatives/parents/guardian) will have to choose which treatment option is good depending on benefits of such option.
Despite all the information given by the doctor, sometimes the patient may still be unsatisfied with what he/she has been told. In such situation, the patient is free and advised to seek a second opinion. Second opinion is the opinion that the patient may seek from another specialist (doctor) regarding his/her health problem and in this case it is cancer. Second opinionmay include confirmation of the diagnosis, more clarification on your primary doctor recommendations or even reassurances that all the options have been explored.
In addition to standard care treatment options, sometimes there are those new treatments or drugs or combination of treatments that have not been approved yet to be used as standard care treatments for a particular cancer (disease) but have shown some promising results that they may help. These type of treatments are called clinical trials.
If there are some clinical trials for your case, the doctor may present to the patient or the patient may ask if there are any clinical trials for the particular cancer case. Over the years, have improved treatments and led to better outcomes to people diagnosed with various diseases including cancer. If you have decided to take part in clinical trial, you can also withdraw at any time
Treatment optionsTreatment of colorectal cancer requires a team of doctors and other health care professionals. This team work together and it is called multidisciplinary team. Team may vary depending on the treatment option for a particular case. But normally multidisciplinary team for treatment of colorectal cancer includes, surgical oncologist, colorectal surgeon, medical oncologist, radiation oncologist, radiation therapist, pathologist and other health care professionals like oncology nurses, physiotherapist and palliative care team. Treatment options include the following;
Surgery is an option that involves the removal of tumor and surrounding healthy tissues by an operation. During the procedure, part of the health colon or rectum and nearby lymph nodes will be removed. This treatment option is performed by a specialized doctor known as surgical oncologist but it may also be done by colorectal surgeon (a surgeon with additional training on treatment of colon, rectum and anus).
Laparoscopic surgery. This is a type of surgery which involves the use of a thin tube called laparoscope which is passed through the abdomen. With this procedure, the incisions are made through which laparoscope will be passed while the patient is under anesthesia.The incisions are small and the recovery time is often shorter than that of a standard surgery.
Colostomy. This is normally used to those with rectal cancer. In this treatment option an opening is made on the abdominal surface through which waste matter exit the body. The waste is collected in a temporally pouch worn by the patient.
Radiofrequency ablation (RFA) and cryoablation. Radiofrequency ablation is also known as cryoablation. It is normally used when dealing with cases that have spread from their original site to other organs such as liver and lungs. RFA involve the use of energy in the form of radiofrequency waves to heat the tumors while cryoablation involve freezing the tumor.This approach can be done through the skin or during surgery.
Side effects of surgerySide effects of surgery depends on type and extent of surgery. Some of the possible side effects of surgery include the following;
Risk of infection.
Pain around the area of surgery.
Irritation around stoma to those who had colostomy.
Reaction from anesthesia.
ChemotherapyChemotherapy is the use of drugs to destroy cancer cells or stop its growth. This treatment is given by a specialized doctor known as medical oncologist. Type of chemotherapy used for treatment of colorectal cancer is known as systemic chemotherapy. In systemic chemotherapy drug gets into the bloodstream to reach cancer cells throughout the body.
Generally chemotherapy is can be given through injection into vein (intravenously) by using a needle or given as a pill or capsule that is swallowed (orally). Chemotherapy can sometimes be given in combination with radiation therapy.
Side effects of chemotherapySide effects of chemotherapy depend on the dose given, type of drug used and periodic time by which it has been used. Some of the possible side effects include the following;
=> Hair loss
=> Nausea and/or vomiting
=> Loss of appetite
=> Feeling tired as result of low red blood cells count
=> Risk of infection due to decreased white blood cells
=> Easily bruising and bleeding as a result of low blood platelets.
=> Changed bowel habits such as constipation or diarrhea
Radiation therapyRadiation therapy is a treatment option that involve using high energy x-rays or other radiation particles to destroy cancer cells. Radiation therapy is given by a specialized doctor known as radiation oncologist. There are two main types of radiation therapy, internal radiation therapy (brachytherapy) and external beam radiation therapy.
External beam radiation therapy involve directing beam of radiation to the tumor from the source (machine) which is positioned outside the body. For treatment of colorectal cancer, external beam radiation therapy is the one that is normally used. For locally advanced rectal cancer, radiation therapy is sometimes given before surgery. It is often combined with chemotherapy a combination treatment called chemoradiation. Radiotherapy is not used to treat early colon cancer.
Side effects of radiation therapy Side effects of radiation therapy to bowel cancer depend on the dose of radiation therapy given. These side effects normally go away soon after completion of treatment but there are medications that may help to relieve some of the effects if they become too severe. Possible side effects include the following;
=> Mild skin reactions at the site of irradiation
=> Loose bowel movement
=> Upset stomach
=> Loss of appetite.
=> Urinary or fecal incontinency.