Colon cancer can cause complications such as bowel obstruction or gastrointestinal (GI) bleeding. Treatments for colon cancer, such as surgery or chemotherapy, can also cause complications.
Colon cancer is the
It’s important to promptly seek medical attention if you develop potential signs or symptoms of bowel cancer.
Although many of the symptoms and complications may be similar to those with less serious causes, it’s important to rule out cancer as early as possible.
Both colon cancer and treatment for colon cancer can cause complications. For some people, the initial signs of cancer are symptoms related to bowel obstruction or bleeding coming from the gastrointestinal tract.
Bowel obstruction occurs when a tumor partially or completely blocks your intestines. Serious obstructions can be life threatening and require immediate surgical treatment. Bowel obstruction can also be a complication of some treatments for your cancer, such as radiation therapy or surgery.
Bowel obstruction is most common in people with
Signs and symptoms of a bowel obstruction can include:
Bleeding is one of the most common signs of colon cancer. GI bleeding is reported in up to 33% of people with colon cancer. You may notice blood in your feces or on your tissue when using the bathroom.
Blood might look bright red if it’s from near the end of your colon or rectum. Blood from higher up in your GI tract might look dark red or black.
Finding blood in your feces isn’t necessarily a sign of bowel cancer. It can also be a sign of other conditions, such as hemorrhoids. However, it’s important to promptly see your healthcare professional any time you suspect GI bleeding.
Malnutrition can develop if you’re unable to consume enough nutrition to support yourself. Some of the treatments for bowel cancer, such as radiation therapy, may affect your body’s ability to absorb nutrients from your food.
Some of the most common side effects of chemotherapy include:
- loss of appetite
- nausea
- vomiting
- diarrhea
Experiencing any of these symptoms might make you more prone to malnutrition.
Learn more about the effects of chemotherapy on your body.
Up to a quarter of people have metastatic cancer at the time of their diagnosis. Metastatic cancer is when the cancer spreads through your bloodstream or lymph system to distant tissues.
Some of the most common places colon cancer spreads to include your:
- liver
- lungs
- lymph nodes
- peritoneum
Cancer that spreads to other tissues can cause many other symptoms. For example, cancer that spreads to your lungs can cause symptoms such as:
- persistent cough
- shortness of breath
- unexplained weight loss
- chest infections
- coughing up blood
- hoarseness
- trouble swallowing
Perforation is a hole in the wall of your intestines. It can develop when a tumor grows through the wall of your intestine. It may also occur after receiving treatment such as chemotherapy if the tumor shrinks quickly.
Perforation can be life threatening and requires immediate medical attention.
Here are some of the potential treatment options for colon cancer complications:
| Complication | Treatment options |
|---|---|
| Metastases | • chemotherapy • targeted therapy drugs • immunotherapy • radiation therapy |
| Perforation | • treatment for the underlying cause • supplementation with nutrients or fluids |
| Bowel obstruction | • surgery • supportive treatments such as fluids through an IV |
| Malnutrition | • treatment for the underlying cause • supplementation with nutrients or fluids |
| Bleeding | • a procedure called endoscopic hemostasis • blood transfusions if you lose a large amount of blood |
Learn more about bowel cancer treatment.
Treatment for colon cancer itself can also cause complications.
Surgical complications
Some of the most common complications following surgery to remove colon cancer are:
- infections
- bowel obstructions
- bleeding from wounds
- urinary complications
- heart or lung complications
- blood clots
- bowel leakage
Chemotherapy
Chemotherapy is one of the most common treatments for colon cancer. Although it can be an effective treatment, it often causes complications such as:
- hair loss
- mouth sores
- loss of appetite
- weight loss
- nausea
- vomiting
- diarrhea
- nail or skin changes
- nerve problems
- redness in your hands and feet
- fatigue
- easy bruising or bleeding
- increased infections
- bowel obstruction
Radiation therapy complications
Radiation therapy can cause complications such as:
- skin irritation around the treated area
- problems with wound healing
- nausea
- rectal irritation
- diarrhea
- painful bowel movements
- blood in the stool
- stool leakage
- bladder irritation
- fatigue
- sexual problems such as vaginal irritation or erectile dysfunction
- bowel obstruction
Learn more about radiation therapy side effects.
Colon cancer can cause complications such as bowel obstruction or bleeding in your gastrointestinal tract. Treatments for colon cancer, such as surgery or radiation therapy, can also cause complications.
It’s important to seek medical attention if you haven’t yet been diagnosed with bowel cancer but you develop potential symptoms. Your doctor can help rule out other conditions that can cause similar symptoms and recommend the best treatments for you.