Stage 4 Colon Cancer

What is stage 4 Colon Cancer?

A patient is said to have stage 4 colon cancer when the cancer has spread from the colon to other body parts, including the lung, brain, liver, and peritoneum. It can be fairly difficult to cure stage 4 colon cancer once it has spread. However, there is a small chance of curing them if the cancer has only spread to small sections of the lungs, liver, and distant lymph nodes.

What are the subtypes of stage 4 Colon Cancer?

Stage 4 colon cancer is divided into three different subtypes 4A, 4B, and 4C. Stage 4A means that the cancer has only spread to one organ or distant site, such as the lungs, but that it hasn’t spread to the peritoneum (the tissue that lines the abdominal cavity). Stage 4A cancer can spread through the bloodstream.

Stage 4V means that the cancer has spread to more than one organ or distant site, such as the liver, lung, and ovary. In stage 4C, the cancer has spread to other parts of the tissue that are lining the abdominal wall and may have also reached other areas and organs [¹].

Stage 4 Colon Cancer staging and diagnosis

Colon Cancer staging

In general, the TNM system is used to describe and classify cancers, including Colon Cancer, where:

T (tumor) describes the size and location of the tumor
N (nodes) indicates whether or not it has spread to nearby lymph nodes
M (metastasis) describes if and how far the cancer has spread from its origin

How common is stage 4 Colon Cancer?

Most studies show that colon cancer occurs in about 1 in 23 men and 1 in 26 women [2]. However, these studies haven’t provided details about how colon cancer is distributed based on stage. However, given that colon cancer is easy to detect (and cure) in its early stages, it can be safe to assume that stage 4 colon cancer isn’t very common.

How is stage 4 Colon Cancer diagnosed?

Doctors may perform several tests to diagnose stage 4 colon cancer. The first step is to perform a colonoscopy at their office. A small camera is attached to a thin tube that the doctor uses to look inside the large intestine and rectum. Patients are asked to drink a liquid that cleans out the colon so that doctors can have a better look with a camera.

The test usually takes about 30 minutes to perform. For a more comprehensive diagnosis, doctors may perform a biopsy by removing a small piece of the tissue in a procedure known as a colonoscopy. The tissue sample is then analyzed under a microscope to look for cancerous cells.

Another way of performing the biopsy is by using a needle. Doctors use a CT scan to guide the needle to the tumor through the skin. Patients are given pain medication at the site to numb the area before getting a needle biopsy. It is worth noting that a needle biopsy isn’t used for tumors inside the colon. A needle biopsy is only used for areas of the body that are easier to reach, such as the liver and lungs.

The following tests are then used to see how far the cancer has spread and identify the stage.

X-Ray: An X-Ray is used to take images of the chest inside the body. This will indicate whether the cancer has spread to the lungs.

CT scan: This X-ray takes detailed pictures of the entire body and reveals whether the cancer has spread to other organs, such as the lungs and liver. Sometimes, the doctor will administer a special dye to their patient before performing the scan. This is done through a vein or a pill. The dye gives a more detailed account of the cancer.
MRI: The MRI provides detailed pictures of the organ and structure inside the body. The test is performed to study the inside of the abdomen and pelvis. A dye may be administered before the test for a clearer picture.
Ultrasound: This test helps doctors understand whether the cancer has spread to the liver or the pelvis.

Stage 4 Colon Cancer Symptoms

Symptoms for stage 4 colon cancer largely depend on where the cancer has spread. In general, most patients may experience the following symptoms (regardless of how the cancer has metastasized):

Presence of blood in the stool
Constipation and diarrhea
Pencil-like stools (an indication that something is blocking the colon)
Lethargy and weakness
Abdominal pain and bloating
Rapid weight loss of over 10 pounds even though the patient hasn’t changed their diet or exercise habits
Nausea and vomiting due to the presence of tumors that lead to an obstruction

Symptoms also depend on where the cancer has spread.

Liver: If the colon cancer has spread to the liver, it may cause loss of appetite, fatigue, itching, swelling in the legs, and jaundice
Lungs: Cancer that has spread to the lungs will cause chest pain, a persistent cough, difficulty breathing, bloody mucus, and weight loss.
Peritoneum: cancer cells that have spread to the abdomen will lead to pain in the stomach, loss of appetite, and abrupt weight changes.
Bones: Colon cancer that has spread to the bone will cause the bone to dissolve, releasing calcium into the blood. Symptoms include bone pain, numbness in the legs, pain in the back, and constipation due to high calcium levels in the blood.

Stage 4 Colon Cancer Treatment

Although stage 4 colon cancer has spread to distant parts of the body, it is still possible to treat it. Treatment is aimed at helping patients live for longer and improve their quality of life. A cure may be possible if the cancer’s spread is restricted. Options for treatment include surgery, chemotherapy, radiation, and immunotherapy, among others.

Stage 4 Colon Cancer {primary/first-line treatment}

The first line of treatment for stage 4 colon cancer is surgery if it has spread to the liver or lungs. It may be possible to cure patients if the cancer has only spread to these organs. But in some cases, surgery may only ease symptoms. Surgery may require the removal of parts of the liver, lungs, or colon that have been affected by the cancer.

Surgeons may also remove nearby lymph nodes since the cancer is known to spread through the lymphatic system.

Chemotherapy: Chemotherapy is often used for killing cancer cells. Patients can get chemotherapy through a tube in a vein or a pill that is easy to swallow. Some patients opt for chemotherapy before getting surgery to reduce the size of the tumors so that doctors can remove them easily. Chemo is also given after the surgery to destroy leftover cancer cells.
Radiation: Radiation therapy uses high X-rays to kill cancer cells. The triamterene may not be able to cure the cancer, but it has been shown to reduce the tumor and relieve symptoms
Ablation and cryotherapy: Ablation is the use of high-energy radio waves to kill cancer cells, while cryotherapy exposes the tumor to freezing temperatures.

The exact treatment plan for stage 4 colon cancer depends on several factors, such as the patient's age, how far the cancer has spread, and overall health. Patients should consult with a multidisciplinary team of health practitioners to review their options.

Other types of treatment for stage 4 Colon Cancer

Doctors may use immunotherapy for treating stage 4 colon cancer. This treatment involves the use of medication to help the immune system kill cancer cells. Immunotherapy is usually prescribed to patients whose cancers have high levels of MSI (microsatellite instability). Common drugs include nivolumab and pembrolizumab.

The FDA has also recently approved the use of encorafenib for treating patients with colon cancer. This drug is often used with cetuximab in adults with terminal colon cancer whose tumors have a certain mutation and have already received treatment [³].

Can stage 4 Colon Cancer be cured?

It may not be possible to cure stage 4 colon cancer in patients because the cancer has spread to distant organs. In rare cases, a cure could be possible if the cancer's spread has been restricted to a few locations in the body. Chemotherapy may be recommended to patients with too many tumor cells before they undergo surgery.

Prognosis: Stage 4 Colon Cancer survival rate

Stage 4 Colon Cancer survival rate

According to the American Cancer Society, the five-year survival rate for stage 4 colon cancer is 14% for distant cancer and 72% for regional cancer [⁴]. With that said people who are diagnosed with colon cancer have a better quality of life and survival rates because of rapid improvements in treatments.

Stage 4 Colon Cancer recurrence rate

The recurrence rate for colon cancer after surgery and chemotherapy is about 30% [⁵]. Colon cancer is likely to recur within the first five years of receiving treatment. A 2003 study found that the cumulative recurrence rate in colon cancer was 100% at four years [⁶]. However, recurrence rates have significantly improved since then.

Stage 4 Colon Cancer growth rate

Stage 4 colon cancer tends to grow at a slow rate over the course of several years. The cancers usually start as polyps that may turn into cancer. Most polyps will not become malignant but could slowly turn cancerous over the course of 10 to 15 years. One study found 76% of patients were diagnosed with liver metastases within a year of receiving a colon cancer diagnosis [⁷].

The growth rate for how stage 4 colon cancer spread depends on how early it was diagnosed, how it was treated, and the cell type, among others.

Lifestyle changes for preventing and managing Colon Cancer

It is recommended that patients make the following lifestyle change after getting diagnosed with colon cancer:

Quit Smoking: Smoking can increase the risk associated with colon cancer and slows down the rate at which the body heals itself.
Restrict Alcohol Consumption: Driving alcohol can also increase the risk of developing colon cancer [⁸].
Eat Healthy Foods: It is important to eat a healthy diet that consists of fruits and vegetables while avoiding processed meats. A high intake of processed meat can increase the risk of colon cancer.
Working Out: Not only does working out help patients maintain a healthy weight, but it can also boost the immune system and has been lined with a lower risk of colon cancer [⁹]. Patients should consult with their doctor for a workout plan that aligns with their goals.
Getting Screened at Regular Intervals: Colon cancer is easy to treat, provided that it is detected at an early stage. This is why it is recommended to get screened for colon cancer through a colonoscopy. This test can identify polyps so that doctors can remove them before they have a chance to become cancerous.

Conclusion

Takeaway

Nearly 52,580 people die from colon cancer, making it the third leading cause of death in both men and women across the US [¹⁰]. The good news is that the death rate from colon cancer is dropping thanks to preventive treatments and early diagnosis. Stage 4 colon cancer can be prevented in patients if they undergo regular screening tests and get treatment before any polyps have a chance of becoming malignant.

In addition, it is important to implement lifestyle changes such as maintaining a healthy weight, eating balanced, and working out to reduce the chance of getting colon cancer. A healthy lifestyle can also improve the survival rate for patients diagnosed with stage 4 colon cancer.