Recognising the symptoms of bowel cancer
Understand the early and advanced bowel cancer symptoms, who is most at risk, and when to see a doctor.
Recognising the symptoms of bowel cancer
Understand the early and advanced bowel cancer symptoms, who is most at risk, and when to see a doctor.
Bowel cancer is a type of cancer that develops in the lining of the bowel, affecting either the colon or the rectum. It usually begins as small, non-cancerous growths called polyps, which can turn into cancer over time if not removed. While common in older adults, bowel cancer can affect people at any age.
Early recognition of the symptoms of bowel cancer can lead to significantly better treatment outcomes. When diagnosed in its early stages, this type of cancer is one of the most treatable forms. However, many cases are only found once the disease has progressed, making timely detection crucial.
Bowel cancer is the second leading cause of cancer-related deaths in Australia, but it doesn’t have to be. About 15,000 Australians are diagnosed each year, and early intervention plays a major role in survival rates.
Bowel cancer is a type of cancer that develops in the lining of the bowel, affecting either the colon or the rectum. It usually begins as small, non-cancerous growths called polyps, which can turn into cancer over time if not removed. While common in older adults, bowel cancer can affect people at any age.
Early recognition of the symptoms of bowel cancer can lead to significantly better treatment outcomes. When diagnosed in its early stages, this type of cancer is one of the most treatable forms. However, many cases are only found once the disease has progressed, making timely detection crucial.
Bowel cancer is the second leading cause of cancer-related deaths in Australia, but it doesn’t have to be. About 15,000 Australians are diagnosed each year, and early intervention plays a major role in survival rates.
What is bowel cancer?
Cancer of the colon or rectum
Bowel cancer refers to malignant tumours that form in the large bowel, which includes the colon and rectum. It usually begins in the inner lining of the bowel wall and may grow through the layers if left untreated.
Develops from polyps
Most bowel cancers start as polyps, which are small growths on the bowel wall. While most polyps are harmless, some can develop into cancer over time. This progression is often slow, making regular screening crucial.
Colon vs. rectal cancer
Although they fall under the same umbrella, colon cancer and rectal cancer differ in location. Colon cancer develops higher up in the large intestine, while rectal cancer occurs in the last 15 centimetres of the bowel.
Prevalence in Australia
Currently, bowel cancer is one of the most commonly diagnosed cancers in Australia. Around one in twelve Australians will be diagnosed in their lifetime, and it is more frequently seen in individuals over the age of 50.
What is bowel cancer?
Cancer of the colon or rectum
Bowel cancer refers to malignant tumours that form in the large bowel, which includes the colon and rectum. It usually begins in the inner lining of the bowel wall and may grow through the layers if left untreated.
Develops from polyps
Most bowel cancers start as polyps, which are small growths on the bowel wall. While most polyps are harmless, some can develop into cancer over time. This progression is often slow, making regular screening crucial.
Colon vs. rectal cancer
Although they fall under the same umbrella, colon cancer and rectal cancer differ in location. Colon cancer develops higher up in the large intestine, while rectal cancer occurs in the last 15 centimetres of the bowel.
Prevalence in Australia
Currently, bowel cancer is one of the most commonly diagnosed cancers in Australia. Around one in twelve Australians will be diagnosed in their lifetime, and it is more frequently seen in individuals over the age of 50.
Common early symptoms of bowel cancer
Changes in bowel habits
Persistent changes in a person’s bowel movements are among the most common early symptoms of bowel cancer. This may include prolonged diarrhoea, constipation, or stools that are thinner than usual.
Blood in the stool
Noticing blood when you go to the toilet should never be ignored. It may appear bright red or be darker and mixed into the stool, making it harder to detect. Even if it seems minor, seek medical attention.
Unexplained weight loss
Losing weight without dietary changes or an exercise routine can be a warning sign. It may reflect the body’s response to cancer, which can alter how nutrients are absorbed or cause increased energy usage.
Persistent abdominal pain
Ongoing pain, bloating, or cramping in the abdomen that doesn’t go away could be a symptom of early bowel cancer. If the discomfort feels different from your usual digestive upsets, speak to a doctor.
Common early symptoms of bowel cancer
Changes in bowel habits
Persistent changes in a person’s bowel movements are among the most common early symptoms of bowel cancer. This may include prolonged diarrhoea, constipation, or stools that are thinner than usual.
Blood in the stool
Noticing blood when you go to the toilet should never be ignored. It may appear bright red or be darker and mixed into the stool, making it harder to detect. Even if it seems minor, seek medical attention.
Unexplained weight loss
Losing weight without dietary changes or an exercise routine can be a warning sign. It may reflect the body’s response to cancer, which can alter how nutrients are absorbed or cause increased energy usage.
Persistent abdominal pain
Ongoing pain, bloating, or cramping in the abdomen that doesn’t go away could be a symptom of early bowel cancer. If the discomfort feels different from your usual digestive upsets, speak to a doctor.
Symptoms of advanced bowel cancer
Severe abdominal swelling or pain
As bowel cancer advances, it can cause significant swelling in the abdomen due to tumour growth or blockage. This may be accompanied by pain that worsens over time and becomes difficult to manage.
Persistent fatigue
Advanced stages of bowel cancer often lead to chronic fatigue, sometimes caused by slow internal bleeding that results in iron-deficiency anaemia. You may feel exhausted even after adequate sleep or rest.
Loss of appetite
Cancer can interfere with your appetite, causing you to feel full after a few bites or lose interest in eating. If you notice these changes along with other gastrointestinal symptoms, seek help.
Nausea and vomiting
If the bowel becomes partially or completely blocked, you may experience nausea or vomiting. This is a sign that food is not passing through the digestive system properly and requires medical help.
Symptoms of advanced bowel cancer
Severe abdominal swelling or pain
As bowel cancer advances, it can cause significant swelling in the abdomen due to tumour growth or blockage. This may be accompanied by pain that worsens over time and becomes difficult to manage.
Persistent fatigue
Advanced stages of bowel cancer often lead to chronic fatigue, sometimes caused by slow internal bleeding that results in iron-deficiency anaemia. You may feel exhausted even after adequate sleep or rest.
Loss of appetite
Cancer can interfere with your appetite, causing you to feel full after a few bites or lose interest in eating. If you notice these changes along with other gastrointestinal symptoms, seek help.
Nausea and vomiting
If the bowel becomes partially or completely blocked, you may experience nausea or vomiting. This is a sign that food is not passing through the digestive system properly and requires medical help.
Who is at higher risk of bowel cancer?
Older age
Age is one of the biggest risk factors. Most people diagnosed with bowel cancer are over the age of 50. The risk continues to increase as you get older, which is why regular screening becomes more important with age.
Family history of bowel cancer
Having a close relative with bowel cancer increases your likelihood of developing the disease. If you have a family history, especially if diagnosed at a young age, speak to your GP about earlier or more frequent screening.
Chronic bowel conditions
People with long-term inflammatory bowel diseases, such as Crohn’s disease or ulcerative colitis, are at higher risk. Ongoing inflammation in the bowel can lead to cellular changes over time, increasing the chance of cancer.
Lifestyle factors
A diet high in red or processed meats and a low fibre intake can contribute to the risk. Other contributors include smoking and limited physical activity. Lifestyle changes can help reduce risk, but don’t remove it entirely.
Who is at higher risk of bowel cancer?
Older age
Age is one of the biggest risk factors. Most people diagnosed with bowel cancer are over the age of 50. The risk continues to increase as you get older, which is why regular screening becomes more important with age.
Family history of bowel cancer
Having a close relative with bowel cancer increases your likelihood of developing the disease. If you have a family history, especially if diagnosed at a young age, speak to your GP about earlier or more frequent screening.
Chronic bowel conditions
People with long-term inflammatory bowel diseases, such as Crohn’s disease or ulcerative colitis, are at higher risk. Ongoing inflammation in the bowel can lead to cellular changes over time, increasing the chance of cancer.
Lifestyle factors
A diet high in red or processed meats and a low fibre intake can contribute to the risk. Other contributors include smoking and limited physical activity. Lifestyle changes can help reduce risk, but don’t remove it entirely.
Concerned about symptoms?
If you’re experiencing any of the symptoms of bowel cancer—whether they are early warning signs or more advanced indicators—it’s important not to delay speaking with a medical professional. Many symptoms can have non-cancerous causes, but only proper testing can rule out serious issues.
Screening is a powerful tool in the early detection of bowel cancer. Even if you don’t have symptoms, participating in regular bowel cancer screening could help identify issues before they become dangerous. If it’s been a while since your last check-up or test, now is the time to act.
Concerned about symptoms?
If you’re experiencing any of the symptoms of bowel cancer—whether they are early warning signs or more advanced indicators—it’s important not to delay speaking with a medical professional. Many symptoms can have non-cancerous causes, but only proper testing can rule out serious issues.
Screening is a powerful tool in the early detection of bowel cancer. Even if you don’t have symptoms, participating in regular bowel cancer screening could help identify issues before they become dangerous. If it’s been a while since your last check-up or test, now is the time to act.
FAQs
Can bowel cancer develop without any noticeable symptoms?
Yes, in some cases, bowel cancer may grow silently, especially in its early stages. That’s why screening programs are so critical, as they can detect hidden blood in the stool or polyps before symptoms begin.
How often should I participate in bowel cancer screening?
In Australia, people aged 45 to 74 are encouraged to take part in the National Bowel Cancer Screening Program every two years. However, if you’re at higher risk, your doctor may recommend more frequent testing.
Are younger adults being diagnosed more often?
Recent studies show an increase in bowel cancer diagnoses in people under 50. While the reasons aren’t fully understood, it highlights the need for awareness across all age groups.
What should I do if I notice something unusual but feel fine otherwise?
Even if you feel generally well, it’s important to investigate any unusual bowel habits or bleeding. Early-stage bowel cancer can be present without significant symptoms, so don’t ignore subtle changes.