According to the reports of the World Health Organization, colorectal cancer is one of the most common tumours in the Arab world, and it is responsible for the largest number of cancer-related deaths after lung cancer. As regards the death rates from colorectal cancer in 2020, these were up to 50 % over more than 1.9 million cases diagnosed.
It is worth noting that the incidence is considered equal between genders, as 55% of colorectal cancer patients are men, while 45% of those diagnosed are women. Fortunately, the cure rates are very high if early diagnosis is made rather than at a later stage. Therefore, in this article, we will shed light on everything you want to know about colorectal cancer: Symptoms, causes, treatment etc., however, let’s first get to know: what is the colon and what is the rectum?
What is the colon?
It is one of the organs of the digestive system. The colon is part of the large intestine. Its length ranges from 1.5 to 1.8 meters and works to process waste to be transported to the rectum.
What is the rectum?
The rectum connects the colon to the anus, which is the last part of the intestine, and its length ranges between 12 and 15 centimeters. It is responsible for retaining waste until it is expelled from the body through the process of defecation.
What is Colorectal cancer?
It is the cancer affecting the colon and the rectum, and it is the result of abnormal growth of cells lining the wall of the colon and rectum. This abnormal growth of cells leads to the emergence of specific symptoms and complications.
Colon cancer causes
The main cause of colorectal cancer is unknown, but there are several factors that increase the chances of developing colorectal cancer, including:
- Genetic factors that are revealed by a family history of colorectal cancer or polyps, especially at a young age.
- Diet poor in fruit and vegetables.
- Excessive intake of processed meat and red meat increases the risk of colon cancer.
- Eating unhealthy foods that contain saturated and hydrogenated fats.
- Practicing bad habits such as smoking and drinking alcohol.
- History of ulcerative colitis or Crohn’s disease may increase your risk.
- Lack of physical exercise
- Diabetes or insulin resistance.
- Obesity.
- Advanced age: colorectal cancer spreads is kore common over 50 years of age, but more recently an increase in the younger. population has been noticed.
Colorectal cancer screening recommendations
Screening of colorectal cancer should start at the age of 45 by looking for the presence of occult blood in the stool. If this is positive, the patient will require a colonoscopy. Some patients with a strong family history will need colonoscopy regardless of fecal occult blood test.
Colon cancer symptoms
- Presence of blood in the stool, which may be light or dark red blood.
- Change in bowel movements with diarrhea or constipation.
- Change in the shape of the stool to the form of a strip or a thin one.
- Iron deficiency anemia.
- Weight loss within a short period of time without specific reasons.
- Abdominal pain that may appear in the form of gas, cramps or flatulence.
- Feeling of not emptying everything in the intestine completely.
- General feeling of tiredness and fatigue.
- Feeling of nausea and vomiting.
It is worth noting here that all these symptoms may appear with other less serious diseases such as Crohn’s disease, ulcers in the intestine, or chronic colitis. But it is of paramount importance to consult with a doctor if you experience some or all of these symptoms.
Early symptoms of colon cancer
Some initial symptoms appear in colorectal cancer, but these symptoms are not specific symptoms of colorectal cancer, but may appear in other diseases. So, if some of these symptoms appear, go to the nearest doctor for reassurance and early examination. These symptoms include:
- Intestinal disorders, including diarrhea and constipation.
- Feeling of pain in the abdomen.
- The presence of blood in the stool, whether it is bright red or dark.
- Notice a decrease in weight without a specific reason.
- Anemia without a specific cause.
Symptoms of colon cancer in women
Colorectal cancer symptoms are similar in both men and women. However, some specific symptoms may arise if the cancer involves the female genital organs like the ovaries, uterus and vagina. An ovarian mass may be caused by spread of the colorectal cancer. Also, vaginal bleeding or passage of stool from vagina may be caused by the tumor infiltrating the vagina.
If you feel any of these symptoms, you should visit your doctor immediately.
Rectal cancer symptoms
Rectal cancer has similar symptoms to colon cancer. However, rectal bleeding is more common and anal pain may occur if the tumor involves the anus.
The difference between symptoms of colon cancer and Irritable Bowel Syndrome (IBS)
Some colorectal cancer symptoms (change in bowel habits, abdominal pain) are similar to those experienced by people affected by Irritable Bowel Syndrome. Irritable Bowel Syndrome is a chronic disease that usually affects individuals less than 50 years of age, and the incidence in women is higher than in men. On the other hand, colorectal cancer is a progressive disease with worsening symptoms, and usually affects people over 50 years of age, and more often men.
Causes of colorectal cancer have been mentioned before. Irritable bowel syndrome is associated with stress, anxiety, depression, and also a genetic predisposition. Symptoms of irritable bowel syndrome include bloating, gas, abdominal pain and cramps, and the same symptoms can be experienced by people with colon cancer and rectal cancer. However, bleeding, anemia and symptoms of bowel obstruction are specific to colorectal cancer.
How is colorectal cancer diagnosed?
It is necessary to diagnose colon and rectal cancer through some specific procedures. It is not possible to diagnose by knowing the symptoms only. Early diagnosis is very important and increases the chance of recovery.
Colorectal Cancer Investigations
colonoscopy
One of the most important and most accurate ways to detect the disease at an early stage is by inserting a long, flexible tube, the endoscope, through the anus, into the rectum, and then into the colon, with a very small camera attached to it. The endoscopist is able to see and detect any changes that occur in the lining of the intestine. The procedure takes from half an hour to an hour. Colonoscopy is a diagnostic and therapeutic procedure that enables the endoscopist to diagnose by seeing the entire colon and rectum and remove any abnormal tissue or polyps.
Taking a sample for examination (biopsy)
A sample is taken from the area affected by the tumor and then sent to a laboratory specialized in pathology to examine this sample under a microscope. This process is done during a colonoscopy.
Fecal occult blood test (FOB)
In this laboratory test, a stool sample is checked for hidden blood. This is one of the primary tests that the doctor resorts to at the beginning of the diagnostic pathway, as it does not require surgical intervention or the use of anesthesia, but it is not a confirming diagnostic test for the diagnosis colorectal cancer. If it is positive, it indicates the presence of hidden blood in the stool and is definitely not the presence of cancer.
Stool DNA test
In this lab test, your stool is checked for the presence of abnormal cells.
Complete blood analysis
A blood sample is taken from the affected patient, and this test indicates the number of red and white blood cells and platelets. Through it, the patient is diagnosed with anemia, a deficiency of red blood cells.
Does blood in stool mean cancer?
Blood in the stool is always a concern as it can be related to the presence of a cancer, although most of the times is due to a benign condition. Blood appears in the stool as a result of bleeding in the intestine. The blood may be bright red and indicate that the blood is bleeding from the lower part of the digestive system, or dark brown to indicate that the origin of the bleeding is away from the lower part of the digestive system, and likely in the upper gastrointestinal tract. There are many other causes of fresh rectal bleeding:
- Hemorrhoids.
- Anal fissure.
- Diverticular disease.
- Inflammatory bowel diseases.
- Infectious diseases.
- Large benign polyps.
- Heavy bleeding from the upper gastrointestinal tract.
Colorectal cancer treatment
The treatment of colorectal cancer is surgical, either with open surgery or minimally invasive techniques (laparoscopy or robotic). Radiotherapy or chemotherapy may be required before or after the surgery.
Dr. Antonio Privitera is one of the most qualified surgeons in the Middle East to treat colorectal cancer either by laparoscopy or robotic surgery. The experience of the surgeon allows for complete excision of the cancer with high chance of cure and a life free of cancer.