Rectum Cancer: Types, Symptoms, Causes, Diagnosis & Treatments

Rectum Cancer: Types, Symptoms, Causes, Diagnosis & Treatments
The rectal cancer tumor spreads by attacking the bowel wall. Some polyps can turn into cancer and begin to grow and penetrate the wall of the rectum.


Cancer is a dreadful disease that has caused the death of millions. Each year, new patients are diagnosed with cancer and, at the same time, many die from this deadly disease.

Cancer can develop in any part of the body, and can spread from the primary location where it originally formed to other parts of the body – not only to surrounding tissue, but also to distant tissue.

When cancer is diagnosed, a patient needs to obtain adequate treatment to destroy the cancerous cells in a timely manner to avoid the cancer spreading to other parts, which makes it more difficult to treat cancer. When cancer is diagnosed at an early stage, it is often possible to completely cure the cancer and remove any cells that are cancerous.

Diagnosed at a more advanced stage, however, means the outlook of the patient would not be as possible as it would have been with an early diagnosis. Cancer in a more advanced stage is more difficult to treat effectively since it often affects larger parts of the body when it has advanced.

The location that cancer is found in is used to determine the particular type of cancer that a patient has. Some forms of cancer are more commonly found amongst the general population than others. In addition to affecting healthy tissue in the body, cancer may also affect the bones and the blood circulatory system.

Amongst the numerous forms of cancer, colon and rectum cancer are particularly widespread amongst the general population. When doing research on the most prevalent types of cancer, cancer of the rectum and colon are usually placed at one of the top locations in these lists. In this report, we are going to explore rectum cancer.

We are going to look at the particular symptoms that people should look out for to help them diagnose rectum cancer at an early stage, as well as look at prevalence of the cancer, risk factors that increases the likeliness of developing this cancer, the particular treatment options that are available for patients with rectum cancer and, of course, we are also going to look at the outlook that people with rectum cancer has.

We will also explore the different stages of rectum cancer to provide more details on how severe the condition may become, as well as to provide the reader with education so that they know what to expect when a doctor diagnoses them with rectum cancer at a particular stage.

What Is The Purpose Of The Rectum And Where Is It Located

The digestive system

The rectum is the portion of the large intestine and acts as a storage pouch for feces before it is evacuated through the anus.

The digestive system is the longest system in the human body and plays a significant role in the digestive process.

Without a properly functioning digestive system, it would not be possible for the human body to thoroughly absorb essential nutrients, which consist of vitamins, proteins, fats and carbohydrates, to ensure the proper functioning of all other systems and organs that form part of the body.

The rectum is part of the digestive system and, while it may not seem to play such a significant role due to not being part of the nutrient absorption organs, the rectum is still important for a functioning digesting process.

The mouth marks the beginning of the digestive tract, where food is chewed to start the process of digestion. After a person chewed their food, the food is swallowed and transported through the esophagus towards the stomach.

In the stomach, certain acids are combined with the food to help with the processing of the food particles and to break the food down into nutrients. After this process, the food is transferred toward the small intestines, where nutrients are absorbed into the bloodstream.

Finally, food is transported to the large intestine, where it moves toward the rectum. The rectum connects the large intestine to the anus cavity. The anus cavity is where waste is disposed of during a bowel movement.

The location of the rectum makes it responsible for the final parts of the digestive system, where waste is moved from the large intestine towards the anus cavity, which allows for its disposal.

Without the rectum, final disposal of waste would not be possible. Obstructions in this particular area of the digestive tract can lead to many symptoms and even some serious health problems.

What Is Rectum Cancer?

As the name suggests, rectum cancer refers to the development of cancer within the rectum, an essential part of the digestive system that is responsible for the removal of waste after nutrients has been extracted from food particles.

It is important to note that rectum cancer is sometimes called colorectal cancer[1], since the rectum is the final part of the colon and cancer within the colon itself is also relatively common in association with rectum cancer.

Even though these two types of cancers are often referred to with the same name, being colorectal cancer, it is still important to know that cancer within the colon and cancer within the rectum are not treated in the same way and they are also dealt with uniquely.

Cancer in the rectum occurs when healthy cells that are found within the tissue in the rectum starts to malfunction. When these healthy cells malfunction, they may start to multiply in an unnatural way and also grow uncontrollably; thus leading to the development of tumors in the particular area.

In some cases, tumors that develop might not contain cancerous cells, but rather be benign, which means it does not pose a risk of spreading to other parts of the body and should not lead to significantly serious symptoms. In other cases, however, the cells that have started to malfunction and caused the formation of a tumor may be cancerous and could pose as a deadly condition should it be left untreated.

Rectum cancer is complicated in many cases and is usually very unique to each patient. To better understand this particular type of cancer, it is important to know about the different types of rectum cancer[2] that may develop in a patient.

Each of these types may develop in a different way and often also requires a different approach when it comes to treatment.

The most common type of cancerous tumor that can develop in the rectum is known as adenocarcinomas. These account for the majority of all diagnosed cases of rectum cancer. Adenocarcinomas develop when cells that are found within the lining of a patient’s rectum starts to malfunction.

When this happens, the cells start to multiply and grow quickly, as we have discussed, and then causes the formation of a tumor in the rectum.

There are some other types of cancerous tumors that may also develop in the rectum, but these are much rarer than adenocarcinomas. The rarer forms of cancerous tumors that can develop in the rectum includes:

Gastrointestinal Stromal Tumors

GIST arise from the interstitial cells of Cajal; This tumor is caused most often by an abnormal KIT gene passed from parent to child.

Gastrointestinal Stromal Tumors: These tumors are sarcomas that are made of soft tissue. The usually develop in other parts of the gastrointestinal tract, but is rarely also found within the rectum.

Gastrointestinal stromal tumors can also develop in connective tissues that are present within the colon, as well as blood vessels in the colon or rectum. Gastrointestinal stromal tumors account for approximately 1% of all cancers that develop in the colon or rectum.

Carcinoid Tumors: This particular type of rectum cancer develops when cells that are responsible for the production of hormones malfunctions within the intestinal tract – in this case, the rectum.

Note that, just like gastrointestinal stromal tumors, carcinoid tumors are also usually found in other parts of the intestinal tract, but can occur in the rectum as well.

Lymphomas: These are also relatively rare types of tumors and is caused by malfunctioning cells that form part of the immune system. While lymphomas tend to develop within the lymph nodes first, but there have been cases where lymphomas developed in the rectum.

Lymphomas only accounts for approximately 0.5% of all cancers that develop in the rectum or colon.

Rectum Cancer Symptoms

Knowing about the different symptoms that rectum cancer may cause is essential not only to those who are at risk, but for the general population as well since any person can develop this particular type of cancer – even if they are not at a particularly high risk of developing cancerous tumors in their rectum.

Before we discuss the particular rectum cancer symptoms to look out for, we would like to note that symptoms can be divided into two particular groups – symptoms and signs[3].

The signs of rectum cancer are usually associated with changes in the suspected patient’s bowel movements. The symptoms, however, relates to a wide area of their body and wellbeing that may be affected adversely by the cancerous tumors that might be developing in their rectum.

Let’s start by looking at particular signs that people should look out for, which may indicate rectum cancer.

Note that experiencing these signs does not necessarily mean a patient definitely has rectum cancer, but they should be a call for concern and any particular individuals experiencing these signs should at least obtain a physical examination from a doctor to rule out rectum cancer and find the problems that are causing them to experience them.
Diarrhea or constipation are often considered signs of rectum cancer, but these particular signs can be caused by many other health concerns as well.

Thus, it is important to look at the other signs as well. A lot of people with rectum cancer find that they are unable to empty all waste during a bowel movement. If changes occur in the shape of a person’s stool, or the size of their stool, it may also be a sign of rectum cancer.

In most cases, stool would be smaller and narrower than it usually is. Another concerning sign of rectum cancer is blood appearing in the suspected patient’s stool. The blood that appears in their stool might exhibit a dark red color, or, in some cases, might be a bright red color.

Apart from the signs we discussed, there are also numerous symptoms that patients should look out for. When multiple symptoms develop, they should seek a medical examination from a healthcare professional to identify what may be causing the symptoms and to identify whether rectum cancer may be to blame.

pain in abdomial area

A change in your bowel habits, experiencing pain in abdomial area can be the origin of rectum cancer.

These symptoms may include:

  • The patient may experience pain in the lower part of their gastrointestinal tract, more specifically within their rectum.
  • Discomfort and pain may also be experienced in the abdominal area, which could also be accompanied by stomach cramps.
  • A bloated feeling is another symptoms that is often associated with rectum cancer. In addition to bloating, patients may also an experience of fullness.
  • Changes in the patient’s appetite is another common problem that people face with rectum cancer. Many patients also experience weight loss without intentionally going on a diet or exerting any effort to reduce their weight.
  • Another symptom that is often experienced with rectum cancer is fatigue and a constant feeling of being tired and weak. This is a symptom that is not only caused by rectum cancer, but also by most other forms of cancer as well.

Rectum Cancer Causes

While it is known how rectum cancer forms, which is when the DNA of cells develop errors, causing them to malfunction, divide and grow uncontrollably.

Even though this is well-known by medical professionals, it is still not completely understood why cells develops errors in their DNA and why they start to divide and grow at such a rapid rate, causing the formation of a tumor, which can become problematic and even lead to death in many cases.

For this reason, specific causes of rectum cancer is not known at the moment, but further research is constantly being conducted to help medical professionals better understand why these cells malfunction and cause a tumor to grow.

Gene mutations

Gene mutations passed from parent to child can also be the reason of rectum cancer.

Rectum Cancer Risk Factors

Even though the specific causes of rectum cancer is still a mysterious topic to medical professionals and researchers that specializes in the field of cancer, they have identified certain risk factors that increases a patient’s risk of developing tumors that are cancerous within their rectum.

By becoming educated about these potential risk factors, people can determine how high of a risk they have to develop this particular type of cancer.

Thus, people with particularly high risks of rectum cancer can discuss their concerns with their healthcare provider and gain frequent screenings and physical examinations to ensure rectum cancer does not develop and, should tumors develop in their rectum, it can be picked up early by a healthcare provider and treated more effectively.

There are many risk factors[4] that have been discovered by medical researchers, so let’s take a look at them one-by-one to understand how each of these risk factors affects a particular individual’s risk of developing rectum cancer.

History Of Cancer In The Intestines

A risk factor that seems to play quite a significant role in increasing a person’s risk of developing rectum cancer is a history of cancer within the intestines.

If a person had cancer within their colon or rectum previously and had it successfully removed through treatment, then the particular person is at a much higher risk of developing rectum cancer later on in their lives once again.
Should rectum cancer return after being successfully treated previously, it is referred to as recurring cancer. The fact that the cancer returns does not necessarily mean it will be more severe or progress at a faster rate than previously.

Family History

Family History

Family history is another factor in determining the risk factor of fearful ailment like cancer.

Another factor that also plays a considerable role in the risk of developing cancer within the rectum is a family history of this particular cancer.

A person who has a mother or father, a child or a sibling, such as a brother or a sister, who had been diagnosed with colon or rectum cancer in the past, then the particular person is also at a much higher risk of developing cancer within their rectum.

Inherited Genetic Mutations

In some rare cases, certain inherited genetic syndromes may also cause a significant increase in a person’s risk of rectum cancer.

There are two particular genetic syndromes that are known to have a large impact on a person’s risk of developing this cancer. These two syndromes include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.

Familial adenomatous polyposis, also known as FAP for short, is rare and leads the development of polyps within the rectum’s lining, as well as in the colon’s lining.

When this particular genetic syndrome is not effectively treated, it has a significant impact on the affected person’s risk of developing cancer in their rectum and their colon. It is important to note that people who have FAP tend to develop colorectal cancer before they reach the age of 40.

The other type of genetic syndrome that also has an effect on the risk of developing rectum cancer is called hereditary nonpolyposis colorectal cancer. For short, this particular syndrome is simply called HNPCC. The disease is also commonly known as Lynch syndrome.

When a person has HNPCC, they are not only at a higher risk of developing cancer in their rectum or colon, but are also at a higher risk of developing cancers in other parts of their body as well.


Age also seems to play a significant factor in the risk of developing rectum cancer. There seems to be a rise in the prevalence of rectum cancer amongst people who are older than the age of 50.

Colon cancer is also more prevalent amongst individuals who are 50 years or older. In younger individuals, rectum cancer is much rarer.



Eating unhealthy foods like red meat can also raise the risk of producing cancerous cells.

The rectum is part of the gastrointestinal tract, where everything that is consumed passes through. Thus, it would only make sense that a person’s diet can have an impact on their risk of developing a cancerous tumor in their rectum.

It has been found that the consumption of red meat on a regular basis causes an increase in the risk of developing rectum cancer. Furthermore, it was also found that a lack of vegetables and foods that are high in fiber may also lead to an increased risk of rectum cancer.

Substance Use

Certain substances have also been linked to increasing the risk of developing colon and rectum cancer. While the increase in risk is not as significant as some of the other risk factors we have discussed here, such as a family history, age and diet, it is still important to consider these risk factors.

Smoking has been linked to a possible increased risk of rectum cancer. The consumption of four or more beverages that contains alcohol on a weekly basis have also been linked to such an increased risk of developing cancer in the rectum or colon.


Obesity Raise

Being overweight or obese have the higher risk of critical health issues in which cancer can be one.

Obesity is a worldwide public health concern that affects the risk of both developing rectum cancer and dying from this particular cancer significantly.

Medical researchers have found obese individuals to be at a significantly higher risk of developing cancer in their rectum.

In addition to this finding, scientists have also found that obesity increases a patient’s risk of losing their battle against rectum cancer, meaning a patient is less likely to survive rectum cancer when they are obese compared to how likely they would have been to survive at a healthy weight.

Inactive Lifestyle

Millions of people are sitting or lying down most of the time. They never obtain any actual physical exercise. An inactive lifestyle, also called a sedentary lifestyle, have been linked to quite a large number of health conditions and adverse reactions on the general wellbeing of the person who is leading such a lifestyle.

Amongst the numerous health effects that an inactive lifestyle has in store for a person, there is the increased risk of developing cancer in their rectum as well. Even slightly increasing physical activity levels may help to reduce the increased risk of rectum cancer that a sedentary lifestyle causes significantly.

Health Conditions

Apart from the risk factors that we have discussed thus far, we also need to mention the fact that certain health conditions has also been linked to a higher risk of developing cancerous tumors in the gastrointestinal tract, such as the colon or, of course, the rectum.

Two particular health conditions that seem to play quite a significant part in increasing a person’s risk of this cancer include:

  • Inflammatory Bowel Disease: Sometimes also called inflammatory bowel syndrome, this disease causes chronic inflammation in the gastrointestinal tract. When chronic inflammation is present in the rectum and the colon, there is a much higher chance that cells within these locations will start to malfunction and become cancerous.
  • Diabetes: Diabetes, specifically type 2 diabetes, has also been shown to increase a patient’s risk of rectum and colon cancer.

Controlling the disease properly does not seem to have too much of an adverse effect on the person’s risk for this cancer, but when a patient fails to manage their disease, a significant increase in their risk can be observed.

In addition to type 2 diabetes, it is also important to note that insulin resistance also plays a part in increasing the patient’s risk of cancer in their colon or rectum.

Colon Cancer Sign Info

Colorectal cancer is a cancer that starts in the colon or the rectum, and its symptoms include bowel habits, contipation, diarrhea,etc.

Rectum Cancer Prevalence And Prognosis

Unfortunately, specific data for rectum cancer alone is not available, but rather combined with statistics for colon cancer due to the fact that these two cancers are often referred to as colorectal cancer.

According to the National Cancer Institute[5], approximately 135, 430 new cases of rectum and colon cancer will be diagnosed throughout 2017.

This figure will account for around 8% of all cancer diagnosis. The estimated death count due to colorectal cancer in 2017 is 50,260, accounting for approximately 8.4% of all cancer-related deaths during the year.

The good news for individuals who have recently been diagnosed with cancer in their colon or rectum, or for those who are suspected of these cancers, is that the five-year survival percentage of these cancers are 64.9%.

This means that more than 50% of all individuals who are diagnosed with colorectal cancer are able to survive for at least five years after their initial diagnosis.

It is also important to note that the rate at which rectum and colon cancer is diagnosed has been declining over the past few years, especially since 1998. The number of deaths caused by these cancers have also seen a steady decline over the past two decades.

The fact that people are becoming more aware of the potential symptoms to look out for has quite a significant impact on the diagnosis and death count associated with rectum cancer.

As people are being educated more thoroughly on symptoms of this cancer, diagnosis can often be made at an early stage. This also means that the treatment administered to the patient may be less invasive and much more effective in curing their cancer.

Even though the five-year survival rate of rectum and colon cancer is relatively high, it is still important to note that the prognosis of this disease is affected by numerous factors.

The advancement of the cancer that a patient has (the stage in which the cancer is) will have the most significant effect on their chance for survival. If the cancerous cells spread to other parts of the body, then the patient’s chances of survival will also be lower than it would have been should the cancer not have spread.

The patients wellbeing also determines how well they may be able to recover from the cancer, and whether or not all cancerous cells from the tumor can be successfully removed are also factors that contributes toward the prognosis of rectum cancer.

Rectum Cancer Diagnosis

The first step toward diagnosing rectum cancer is a physical examination, which would be followed by a series of questions, as well as a look at the patient’s medical history.

These are all important steps for a doctor to take, especially if they suspect rectum cancer from the symptoms that the patient is complaining about. The doctor may also ask the patient about his diet, general wellbeing, activity level and whether anyone closely related to them have had colon or rectum cancer in the past.

In addition to these questions and a physical examination, a digital rectal exam, which is also known as a DRE, will also most likely be conducted.

During a digital rectal exam, a healthcare professional will insert a finger into the rectum of the patient. The finger will be covered with a glove, and the glove will be well lubricated to avoid tearing of the anus cavity or other potential damaging effects.

During this particular examination, the doctor will try to determine if they can notice any particular aspects of the patient’s rectum that feels unusual, such as lumps.

Should the doctor suspect rectum cancer, they may order a series of tests to be conducted on the patient to make an accurate diagnosis.

Performing these tests are essential and rectum cancer cannot be officially diagnosed without knowing for certain that it is, indeed, cancerous cells that have formed a tumor in the patient’s rectum. This is also important to know as some of the symptoms caused by rectum cancer may also be caused by another health condition.


A colonoscopy examines whether any polyps detected in the rectum or not.

A colonoscopy is often the first test that is done to determine whether a patient might have cancerous tumors in their rectum. A colonscope is used during this procedure, which is a small instrument that looks like a tube.

At the end of the tube, there is a lens that is used to display images on a screen during the examination, as well as a light to assist with seeing what is going on in the patient’s rectum. A colonoscopy is performed to see if any polyps can be detected in the rectum, as well as to see if any other signs of cancer can be identified.

Should the doctor performing the colonoscopy identify anything that looks suspicious, they may use a specialized tool that can be equipped to the colonscope to remove a small part of the polyps, which will be examined for signs of cells that might be cancerous.

The removal of tissue from within the rectum is also known as a biopsy. Once tissue has been extracted, the doctor may send it to a laboratory for further testing to see whether it is, indeed, cancerous.

Two particular types of tests are usually performed on these tissue samples, including a reverse transcription-polymerase chain reaction tests, or a RT-PCR for short, and an immunohistochemistry test.

Apart from a biopsy, a carcinoembryonic antigen assay, or a CEA, may also be conducted on the patient. This test can be done before a colonoscopy is conducted since it only requires extraction of blood samples from the patient, and no invasive measures, such as removing tissue from the rectum is required.

During a carcinoembryonic antigen assay, the patient’s blood sample is tested to determine the level of carcinoembryonic antigens that are present in their bloodstream.

These antigens can be released by both healthy cells and cells that have turned cancerous, but when the level of carcinoembryonic antigens in the body is too high, it may indicate rectum cancer or another type of cancer in the patient’s body.

Rectum Cancer Treatment

Rectum cancer first needs to be officially diagnosed by a healthcare professional before it can be treated effectively.

During the diagnosis, the healthcare professional that is examining the patient needs to identify the stage at which the cancer is in, how severe the cancer is and whether it has spread or are only present within the rectum at the time of diagnosis.

All of these factors will help the healthcare professional develop a suited treatment plan to help get rid of the cancerous cells and cure the patient of rectum cancer.

According to the American Cancer Society[6], rectum cancer is usually treated based on the stage it is in. The less severe the stage, the less invasive the treatment procedures would be.

When the cancer has not spread to other parts of the rectum, except for the inner lining, and has not grown too much yet, it is classified as stage 0. In such a case, a polypectomy can be conducted to remove polyps that contain cancerous cells.

Transanal resection or local excision options may also be utilized in the case of stage 0 rectum cancer. Further treatment is usually not necessary with this stage of rectum cancer since the removal of the cancerous tissue usually takes care of the cancer.

When the cancerous cells spreads deeper into the lining of the rectum, yet still remains restricted to the rectum, it is called stage 1 rectum cancer.

In such a case, surgery is also usually the recommended form of treatment, similar to stage 0 rectum cancer. The polyps are removed during surgery – in this case, however, more than one surgical procedure may be required should all cancerous tissue not be removed during the first session.

In more advanced stages of rectum cancer, additional treatment measures may be required to treat a patient with this particular type of cancer.

In addition to surgery, two other options can also be administered to the patient to help destroy cancerous cells. These options might be utilized prior to the surgery, as well as after the surgery to remove any cancerous tissue that might have remained after polyps were surgically removed.

radiation therapy

Cancer treatment includes radiation therapy which kills cancerous cell.

The two additional treatment measures that may be administered to the patient, in addition to surgery, includes:

  • Chemotherapy: A treatment option where drugs are used that have been designed especially for killing off cancerous cells in the body.
  • Radiation therapy: With this form of treatment, specialized high-frequency radio waves are utilized and pointed directly at the rectum – specifically the part of the rectum where the cancerous tumors can be found. These radio waves then assists with neutralizing the cancerous tumors and killing of cells that have become cancerous.

Treating rectum cancer becomes more complicated and difficult when a patient is diagnosed with stage IV rectum cancer. In such a case, the cancer has spread through the rectum’s lining and moved toward distant parts of the body through the patient’s bloodstream.

The particular treatment measures that would be administered to a patient with such an advanced stage of rectum cancer would depend on where the cancer has spread to.

For example, if the cancer spreads to the liver, a specialized treatment may be given to the patient through a particular artery that leads the treatment directly to the liver. Other treatment options are also available when the cancer spreads to other parts of the body, such as the lungs.

Read More: Pancreatic Cancer: Types, Symptoms, Causes, Diagnosis And Treatment


Cancer in the rectum affects millions of people, and any person can be at risk of developing the disease. There are some indications that some are at a higher risk of developing the disease; thus becoming education about the potential risk factors that increases the risk of this particular cancer is vital.

Should a patient be at a higher risk, it is important for them to discuss the concern for rectal cancer with a doctor and to obtain regular screenings. When rectal cancer is diagnosed early, it can often be treated successfully and metastasis of the cancer can be avoided.

Later stages of this cancer may be more serious and lead to fatal symptoms, as well as the metastasis of the disease, which means the cancerous cells would spread to other parts of the patient’s body, apart from their rectum.

In this report, we looked at various important aspects of rectum cancer to help the reader become more education about potential symptoms to look out for, as well as to educate the reader about how rectal cancer is diagnosed and the particular treatment options that may be provided to them should they be diagnosed with the disease.

Knowing about these factors are important, not only for those who have been diagnosed with the disease, but for any person to ensure they know when they should seek medical attention and to ensure the cancer can be detected while it is still in an early, non-invasive stage.

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