What are the symptoms of bowel cancer? Causes and treatment methods

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What you need to know about bowel cancer

Bowel cancer is among the most common types of cancer seen in the digestive system and may not always show clear symptoms in the early stages. For this reason, the symptoms of bowel cancer can often be confused with other digestive system disorders or may go unnoticed for a long time.

While various factors, from genetic predisposition to lifestyle, play a role in the development of bowel cancer, early diagnosis of the disease is one of the leading factors that directly affects treatment success.

In this article, we discuss frequently asked topics, from what bowel cancer is to its symptoms, risk factors, and treatment options. We also touch on more specific conditions, such as small bowel cancer and duodenal cancer.

What is bowel cancer?

Bowel cancer is a type of cancer that occurs when cells in the colon or rectum multiply uncontrollably. In most cases, the disease originates from polyps that develop in the intestinal wall and are initially benign. Over time, some polyps may undergo cellular changes and become cancerous, and if left untreated, they may spread to deeper layers of the bowel tissue.

The course of the disease may vary depending on the location and size of the tumor and whether it has spread to surrounding tissues. Bowel cancer, which can be difficult to detect in the early stages, may progress silently. As the cancer advances without being noticed, changes in bowel habits and various digestive system-related symptoms may appear.

Bowel cancer is generally evaluated in two main groups: colon cancer and rectal cancer. Although these two types share similar characteristics, there are some differences in terms of tumor location, treatment planning, and disease progression. Therefore, determining in which part of the bowel the cancer has developed after diagnosis plays an important role in planning the treatment process.

What are the symptoms of bowel cancer?

While the symptoms of bowel cancer can vary depending on the location of the tumor and the stage of the disease, the most common symptoms can be summarized as follows:

• Long-lasting diarrhea or constipation
• Blood in the stool
• Stool that is thinner than usual
• A feeling that the bowel has not completely emptied after using the toilet
• Abdominal pain, cramps, or bloating
• Unexplained weight loss
• Persistent fatigue and weakness
• Anemia
• Decreased appetite

It should be noted that these symptoms are not specific only to bowel cancer. These symptoms may also be seen in health problems such as intestinal infections or inflammatory bowel diseases.

However, especially in cases such as blood in the stool, persistent changes in bowel habits, or unexplained weight loss, it is important to consult a specialist without delay.

Another point that should be emphasized regarding symptoms is that the severity of these symptoms may not always be parallel to the extent of the disease. While some people may experience noticeable complaints in the early stage, some patients may not develop any noticeable symptoms until advanced stages.

What causes bowel cancer?

Bowel cancer develops as a result of genetic changes that occur in bowel cells. These changes disrupt the normal growth and renewal pattern of cells, causing them to multiply uncontrollably.

However, it is not possible to point to a single factor in the formation of the genetic changes that initially appear and cause the disease. There are a number of factors that may increase the risk of bowel cancer. The most prominent of these factors can be listed as follows:

• Advanced age: Although the disease can be seen at any age, the risk increases with age.
• Family history: The risk is higher in people who have first-degree relatives with bowel cancer.
• Bowel polyps: Some types of polyps in particular may have the potential to become cancerous over time.
• Inflammatory bowel diseases: Ulcerative colitis and Crohn’s disease that continue for many years may lead to permanent changes in bowel tissue.
• A diet rich in processed and red meat: Eating habits that are low in fiber and high in fat may increase the risk.
• Sedentary lifestyle: Lack of regular physical activity may negatively affect bowel health.
• Excess weight and obesity: Fat accumulation, especially around the abdominal area, is associated with certain types of cancer.
• Smoking: Tobacco products can affect not only the lungs but also the digestive system.
• Excessive alcohol consumption: Long-term and high amounts of alcohol consumption are among the risk factors.

Having one or more of these factors does not necessarily mean that a person will develop bowel cancer. On the other hand, the disease may also occur in people who do not have any of the risk factors listed above.

Can the symptoms of small bowel cancer be noticed in the early stage?

Small bowel cancer is one of the types of cancer that is difficult to detect in the early stage. The main reason for this is that the small intestine is located in a deep part of the digestive system and the disease does not cause symptoms in its initial stages. For this reason, many patients may not notice the problem until the symptoms begin to affect daily life.

Symptoms of small bowel cancer that may be seen in the early period include intermittent abdominal pain, a feeling of indigestion, nausea, decreased appetite, or unexplained fatigue. Most of the time, these symptoms can be confused with other digestive system disorders.

As the disease progresses, symptoms may become more noticeable. Tumors that develop in the small intestine may especially make intestinal passage difficult, leading to bloating in the abdominal area, pain that increases after meals, and in some cases, intestinal obstruction. On the other hand, symptoms frequently seen in colon cancer, such as changes in bowel habits and blood in the stool, may not always be prominent in small bowel cancer.

Are the symptoms of duodenal cancer different?

The symptoms seen in duodenal cancer may differ from other bowel cancers in some aspects. This is because this region is located between the stomach and the small intestine and plays an important role in the digestive process.

Depending on the location of the tumor, symptoms may appear more related to the upper digestive system. The prominent symptoms of duodenal cancer can be listed as follows:

• A feeling of fullness in the stomach area after meals
• Frequently recurring nausea and vomiting
• A feeling of early satiety
• A feeling of pressure or discomfort in the upper abdomen
• Difficulty digesting food
• Unexplained iron deficiency anemia
• Yellowing of the skin and whites of the eyes
• Dark-colored urine
• Light-colored stool

Jaundice is one of the notable findings in duodenal cancer. If the tumor puts pressure on the bile ducts, bile flow may be blocked, and yellowing of the skin may occur as a result. This symptom is generally not an expected finding in tumors originating from the colon.

In addition, in some patients, tumors that develop near the stomach outlet may make it difficult for food to pass into the intestines. In this case, complaints such as vomiting shortly after meals, a marked feeling of bloating, and difficulty eating may be seen. Therefore, it is important not to attribute long-lasting upper digestive system complaints only to stomach-related problems and to have them evaluated in detail when necessary.

Are the symptoms of stomach and colon cancer the same?

Although stomach and colon cancer may have some common symptoms, the two diseases do not show symptoms in exactly the same way. General findings such as weight loss, loss of appetite, weakness, and anemia may be seen in both types of cancer. However, the prominent complaints may differ depending on the location of the tumor.

In stomach cancer, symptoms are more related to the upper part of digestion. Complaints such as discomfort in the stomach area after meals, indigestion, heartburn, early satiety, and difficulty swallowing may be more prominent. Nausea and vomiting may also be seen in some patients.

Among the symptoms of colon cancer, changes in bowel movements are more notable. Long-lasting constipation or diarrhea, changes in the shape of stool, a feeling of not being fully emptied after defecation, and rectal bleeding are more commonly seen. These symptoms occur because the disease directly affects bowel functions.

Another important difference between the two diseases is the way bleeding appears. In bleeding originating from the stomach, the stool may become almost black in color, whereas in bleeding originating from the colon, red or dark red blood in the stool is more likely to be seen. However, this situation may not appear in the same way in all patients.

What does one line mean in a bowel cancer test result?

The expression “one line” in a bowel cancer test result is generally associated with home fecal occult blood tests or some rapid screening kits. Although how the results are interpreted may vary in these types of tests, in most tests, seeing only the control line means that the test has given a negative result.

A negative result indicates that there is no detectable level of blood in the stool during the test. However, this does not mean that the person definitely does not have bowel cancer. This is because some bowel tumors may not always cause bleeding, or bleeding may not have occurred during the period when the test was performed.

Therefore, although a one-line result is generally considered normal, further evaluation may be needed in the following situations:

• Presence of symptoms suggestive of bowel cancer
• A family history of bowel cancer
• Previous detection of bowel polyps

On the other hand, since the meaning of the lines in the result window may differ in some tests, the explanations in the test instructions should be taken into account for the most accurate interpretation. However, if you have any doubts about this issue, it would be a better choice to be examined by a specialist.

Which methods are used for bowel cancer treatment?

When planning bowel cancer treatment, the location of the tumor, the stage of the disease, and the patient’s general health condition are taken into consideration.

The aim of the treatment process is not only to remove the cancerous tissue. It is also intended to prevent the spread of the disease and preserve quality of life. For this reason, more than one treatment method may be used together in many patients.

The main methods used in bowel cancer treatment are as follows:

• Surgical treatment: It is one of the most commonly used treatment methods in bowel cancer. Especially in the early stages, the part of the bowel where the tumor is located and, when necessary, the surrounding lymph nodes may be removed. Different surgical techniques may be preferred depending on the spread of the disease.
• Chemotherapy: This is a drug treatment used to destroy cancer cells or slow their growth. It may be applied before surgery to shrink the tumor and after surgery to target remaining cancer cells.
• Radiotherapy: It aims to damage cancer cells with high-energy rays. It may be an important part of the treatment plan, especially in bowel cancers that develop in the rectal region.
• Targeted therapies: Drugs that target specific characteristics of cancer cells are used. These treatments may not be suitable for every patient and are usually planned after the characteristics of the tumor are evaluated.
• Immunotherapy: This is a treatment approach that helps the immune system recognize and fight cancer cells. Effective results may be achieved especially in tumors with certain genetic characteristics.

Regular follow-up is also of great importance throughout the treatment process. The course of treatment is evaluated through imaging methods, blood tests, and follow-up examinations, and changes may be made to the treatment plan when necessary. Today, thanks to developing surgical techniques and new-generation drug treatments, more successful results can be achieved in many patients.

Can bowel cancer be fatal?

Bowel cancer is a serious disease that can be life-threatening when left untreated or when diagnosed at advanced stages. However, it would not be correct to say that the same outcome will occur for everyone who receives this diagnosis today.

Treatment success is higher especially when the cancer is detected while it is still limited to the bowel. At this stage, it may be possible to fully control the disease with the treatments applied. Therefore, early diagnosis is considered one of the most important factors in bowel cancer.

On the other hand, if the disease has spread to the liver, lungs, or other organs, the treatment process may become more complex. However, even in advanced stages, surgical methods, drug treatments, and other modern approaches can slow the progression of the disease, control symptoms, and extend life expectancy.

The diagnosis itself is not the only factor that determines whether bowel cancer will be fatal. When the disease is detected, how early treatment is started, and the person’s general health condition also directly affect the process. Therefore, it is very important not to ignore long-lasting digestive system complaints.

Frequently Asked Questions

Is rectal bleeding a symptom of bowel cancer?

Rectal bleeding may be one of the symptoms seen in bowel cancer, but it is not sufficient as a symptom on its own. Hemorrhoids, anal fissures, intestinal infections, and some inflammatory bowel diseases can also cause similar symptoms.

However, bleeding that is unexplained, recurrent, or accompanied by changes in bowel habits should definitely be evaluated. A doctor’s examination and the tests recommended by the doctor are very important in determining the source of the bleeding.

Where does bowel cancer pain spread?

Pain caused by bowel cancer is not felt in the same area in every patient. Depending on the location of the tumor, discomfort, a feeling of pressure, or cramp-like pain may occur in different parts of the abdomen. In some people, the pain may spread toward the lower back or groin. When the disease progresses or an intestinal obstruction develops, the severity of the pain may increase and become more persistent.

How many times a day does a bowel cancer patient go to the toilet?

It is not possible to give a clear number for how many times a day a person with bowel cancer goes to the toilet. While some patients may feel the need to defecate frequently, others may experience long-lasting constipation.

What matters more than the number of toilet visits is persistent changes in the person’s normal bowel habits. If patients suddenly begin going to the toilet frequently or, conversely, if the frequency of defecation significantly decreases, this is a situation that should be taken into consideration.

How can hemorrhoid and bowel cancer symptoms be distinguished?

Hemorrhoids and bowel cancer may have some common symptoms. Rectal bleeding in particular can be seen in both conditions. However, in hemorrhoids, bleeding is usually bright red and is often noticed during defecation.

In bowel cancer, bleeding may be accompanied by symptoms such as changes in bowel habits, unexplained weight loss, anemia, and persistent fatigue. Since it is not possible to make a definite distinction between the two based only on symptoms, medical evaluation is necessary, especially in long-lasting complaints.

Can bowel cancer be detected with a blood test?

Blood tests cannot directly diagnose bowel cancer. However, they may provide some clues related to the disease. For example, anemia that develops due to long-term hidden bleeding may cause the doctor to request more detailed examinations.

Methods such as colonoscopy and, when necessary, biopsy are used for the definitive evaluation of bowel cancer. Therefore, a normal or abnormal blood test result alone is not sufficient to reach a definite conclusion.