Colorectal Cancer Treatment & Surgery

What is Colorectal Cancer?

Colorectal cancer is the most common cancer in many countries. It is a treatable and preventable cancer. The best way for prevention is in routine screening followed by lifestyle modifications. Screening is advisable for anyone at the age 50 and above in Singapore. 

In the US, that age is lowered to 45. As colorectal cancer develops from polyps, the best way to prevent them is to remove them before they develop. During this phase, including early cancer, individuals are mostly asymptomatic. 

Thus, even without symptoms, everyone should start screening once they reach the advised age. Those with a strong history or other risk factors should consider screening at an earlier age.

What are the Risk Factors for Colorectal Cancer?

There are many risk factors for colorectal cancer, including:

Modifiable risk factors:

  • Smoking
  • Obesity
  • Inadequate dietary fiber
  • Overconsumption of processed meat
  • Lack of physical activity / exercise 

Non modifiable risk factors:

  • Age
  • Personal history of colorectal cancer or polyps
  • Strong family history of colorectal cancer or related cancers
  • Inflammatory bowel disease
  • Hereditary syndromes like Familial Adenomatous Polyposis, Lynch, Peutz Jegher’s etc. 

What are Most Common Symptoms of Colorectal Cancer?

It’s estimated that in 2020, over 1.8 million people will be diagnosed with colorectal cancer, which is why it’s so important to know the potential symptoms.

In the early stages of colorectal cancer, it’s common to not experience any symptoms at all. This is why regular screening is so important in order to catch the cancer in its earliest stages. However, when symptoms do present themselves, they can be very subtle and may include the following:

  • Blood in the stools. If you notice blood in your stools, you should seek medical advice immediately, as this could be a sign of early colorectal cancer.
  • Changes in usual bowel habits. If you’re experiencing either constipation or loose stools, or a sudden change in your usual pattern of bowel movements, this could indicate the presence of colorectal cancer.
  • Abdominal pain and tenderness or bloatedness. If you’re experiencing recurring abdominal pain and tenderness, or a feeling of bloatedness, it may be a sign of colorectal cancer.
  • Weight loss with no reason. If you’re suddenly experiencing an unexpected weight loss, with no change in diet or exercise, this could be a sign of colorectal cancer.
  • Anaemia (low blood count). If your red blood cell count is lower than normal, this could be a sign of a loss of blood from the intestine and that could be a sign of colorectal cancer. 
  • A feeling that the bowel does not empty completely. If, even after having a bowel motion, you feel as though your bowels haven’t completely emptied, this could be an indication of colorectal cancer.

It’s important to remember that any of these symptoms may not necessarily be an indication of colorectal cancer, and that other medical conditions may be present. 

However, if you’re experiencing any of the above symptoms, it’s important that you seek medical attention. Your doctor will be able to rule out any other potential causes, or may suggest further tests such as a colonoscopy, which can help detect early signs of colorectal cancer.

How Does Colorectal Cancer Spread?

Colorectal cancer, also known as colorectal adenocarcinoma, is a cancer that affects the colon and rectum. It is the third most common cancer in the United States, and is the second leading cause of cancer death. Colorectal cancer is a complex disease, and much of what we know about how it spreads is still being studied and understood.

The majority of colorectal cancer begins in the lining of the colon or rectum, and it can spread through these tissues and into adjacent organs. As the cancer cells spread, they can migrate through the walls of the colon or rectum and into the fatty tissue around the colon and rectum. 

This is known as local invasion and is the most common way colorectal cancer spreads. In addition to local invasion, colorectal cancer can potentially spread through the lymphatic channels to the neighboring lymph glands. This is known as lymph node metastasis, and it is the common way colorectal cancer spreads to other parts of the body. 

The cancer cells can also spread via the blood vessels to other parts of the body such as the liver or the lungs. This is known as distant metastasis, and is much less common than lymph node metastasis. The spread of colorectal cancer is a complex process, and knowing how it spreads can help inform doctors about the best course of treatment for their patients. 

Treatment options for colorectal cancer often depend on the stage of the cancer and how far it has spread. Early detection and regular screenings are important for helping to detect colorectal cancer as early as possible, when it is most likely to be treated more effectively.

How is Colorectal Cancer Diagnosed?

Colorectal cancer is a leading cause of death from cancer. The chance of survival is higher when the cancer is detected early, making diagnosis and screening for colorectal cancer important.

The diagnosis of colorectal cancer begins with understanding a person’s risk factors, such as age and family history of colorectal cancer. Those over 50 years of age, or those with a family history of colorectal cancer, should begin screening for colorectal cancer.

Screening tests used to detect colorectal cancer or other problems, even when a person has no symptoms, include:

  • Stool Tests. Stool tests can detect blood in the stool which may be a sign of colorectal cancer.
  • Flexible Sigmoidoscopy. This test uses a thin flexible tube with a light and a tiny camera to look for abnormalities in the lower part of the colon.
  • Colonoscopy. This is the most comprehensive test used to detect colorectal cancer. It uses a long flexible tube with a light and a tiny camera that looks at the entire colon. It can detect abnormal growths called polyps that can be removed during the procedure.

In addition to the tests mentioned above, your doctor may also perform a physical examination and blood tests to confirm the diagnosis.

If any of the tests come back positive or show signs of colorectal cancer, your doctor may recommend a biopsy to determine if the cells are cancerous. A biopsy is the removal of a small sample of tissue from the area of concern to be examined under a microscope.

If colorectal cancer is diagnosed, your doctor will determine the stage of the cancer, which will help guide treatment options. The stage of the cancer will depend on the size of the tumor, whether it has spread, and where it has spread.

Early detection is key when it comes to colorectal cancer. If you are over 50 or have a family history of colorectal cancer, it is important to talk to your doctor about screening. If you have any of the symptoms of colorectal cancer, it is important to seek medical attention to get the proper diagnosis and treatment.

What are the Treatment Options for Colorectal Cancer?

Surgery is the most common and important treatment option for colorectal cancer. During surgery, the surgeon removes the section of the large intestines that contains the cancer. All the neighboring lymph glands will also be removed because if the cancer is to spread, it often spreads to the lymph glands first. 

The remaining ends of the intestine will then be re-connected. If the cancer is too close or has invaded the anus, the colon cannot be joined; an artificial opening on the abdominal wall for the colon, called a colostomy (or stoma), may be required. 

This opening allows waste to be removed from the body when the anus cannot be used or has to be removed. A colostomy may be temporary or permanent. In some cases, radiation therapy and/or chemotherapy may be used in conjunction with or in place of surgery. 

Radiation therapy uses high-energy rays to kill cancer cells and shrink tumors. It is usually given after surgery to help prevent the cancer from coming back. Chemotherapy uses medications to kill cancer cells. It may be used before surgery to shrink the tumor, after surgery to kill any remaining cancer cells, or both.

Colorectal cancer is a serious health condition, but with proper treatment, it can be successfully treated. Treatment options depend on the size, location and stage of the cancer and the person’s overall health. It is important to discuss all treatment options with your doctor so that you can make an informed decision about which treatment is right for you.

What is the Outlook for Colorectal Cancer?

The key to successful treatment of colorectal cancer is early detection. Fortunately, there are several screening tests that can help find cancer before it progresses. These tests are not only important for individuals with known risk factors, such as a family history of colorectal cancer, but for all adults aged 50 or older. 

Screening tests can help find polyps (non-cancerous growths) that could turn into cancer, as well as cancers that have not yet spread. When detected in its early stages, between 80% and 95% of colorectal cancer patients can be cured. Treatment options include surgery, radiation, chemotherapy, and/or targeted therapies. 

If a patient is diagnosed with advanced colorectal cancer, the cure rate drops to 50% or less. Fortunately, due to improved surgical techniques and better nursing care, surgeons can now operate on individuals with low complication rates, as well as those who were once considered too old for surgery or when the cancer was thought to be too advanced.

Overall, the outlook for colorectal cancer is improving. The earlier the cancer is detected, the better the chances of successful treatment and recovery. If you are at risk for colorectal cancer, talk to your healthcare provider about screening options.

Frequently Asked Questions

  • What are the first signs of colorectal cancer?

    Early colorectal cancer has no symptoms. The early symptoms can also vary from individual. The main way by which colorectal cancer is detected in early stages is through screening. Some patients with early stage colorectal cancer can have the following symptoms:

    1. Blood in stools
    2. Constipation
    3. Abdominal bloatedness
    4. Anemia being picked up by routine blood test

  • Is colorectal cancer curable?

    It depends on the stage of cancer. Stage I to III have favorable cure rates. Stage IV colorectal cancer will have variable outcomes. Some patients can still achieve cure with comprehensive treatment while others can have disease control with chemotherapy alone.

    The more extensive the metastasis, i.e. the more lesions or the more organs involved, the less likely the is the probability of cure. With the use of targeted therapy and immune checkpoint inhibitors, more options exist for patients with advanced disease and some continue to have a reasonable quality of life with palliative treatment.

  • What is the survival rate for colorectal cancer?

    From the Singapore Cancer registry, drawing from 2016-2020 data, the 5-year age-standardized relative survival rate for colorectal cancer is 61.8% in males and 62.5% in females. In simple terms, this alludes to an average of approximately 61.8% of male patients (of all ages and all stages) surviving beyond 5 years upon the diagnosis and 62.5% for the female counterparts.

    Clearly, early stage patients survive way better than late stage patients and hence these statistics are mainly used for national health policies and do not apply to individuals with different cancer biology.

  • How can colorectal cancer be prevented?

    The most effective form of prevention is through regular screening. The main reason is because there is no single factor that accurately predicts the occurrence of an undetected mutation in a single cell which ultimately results in cancer. There are however some modifiable risk factors to lower the overall risk of having such mutations occur. These are:

    • Smoking
    • Obesity
    • Inadequate dietary fiber
    • Overconsumption of processed meat
    • Lack of physical activity / exercise

    By avoiding these risk factors, the chance of having cancer is significantly lowered.

  • How is colorectal cancer typically detected?

    It is detected through a colonoscopy and biopsy. However, there are some patients who present with an incidental finding on another test like a CT scan or PET scan. This is not unusual as these scans are common modalities used for patients with a history of cancer.

    There are also instances where a mass is felt by a doctor on physical examination either over the abdomen or during a digital rectal examination. Upon detection of the mass, it is imperative to have an urgent colonoscopy or sigmoidoscopy to confirm or exclude the diagnosis of colorectal cancer.

  • Is pooping with colon cancer painful?

    This is usually not a symptom for colorectal cancer. In fact, this is usually due to anal fissures or hemorrhoids. The reason is that colorectal cancer usually starts from the inner lining of the intestine which does not bear somatic pain fibers that give us the same kind of pain we feel from our skin.

    Hence, most colorectal cancer patients do not have pain upon diagnosis! Having said this, some patients may have cancers near the anal region which then can lead to painful defecation (or pooping with pain). This highlights the importance of seeking for a simple consultation to determine the need for further testing.

  • Can hemorrhoids turn to cancer?

    No. There is no risk for hemorrhoids to turn into cancer at all. Although cancer co-exist with hemorrhoids but this is not because of a malignant transformation of the hemorrhoid tissue. The clear understanding is because they are entirely two different types of tissue and the underlying pathophysiology is different.