Rectal cancer

Diagnosis

Rectal cancer diagnosis often begins with an imaging test to look at the rectum. A thin, flexible tube with a camera may be passed into the rectum and colon. A sample of tissue may be taken for lab testing.

Rectal cancer can be found during a screening test for colorectal cancer. Or it may be suspected based on your symptoms. Tests and procedures used to confirm the diagnosis include:

Colonoscopy

Colonoscopy is a test to look at the colon and rectum. It uses a long, flexible tube with a camera at the end, called a colonoscope, to show the colon and rectum. Your healthcare professional looks for signs of cancer. Medicines are given before and during the procedure to keep you comfortable.

Biopsy

A biopsy is a procedure to remove a sample of tissue for testing in a lab. To get the tissue sample, a healthcare professional passes special cutting tools through a colonoscope. The health professional uses the tools to remove a very small sample of tissue from inside the rectum. The tissue sample is sent to a lab to look for cancer cells.

Other special tests give more details about the cancer cells. Your healthcare team uses this information to make a treatment plan.

Tests to look for rectal cancer spread

If you're diagnosed with rectal cancer, the next step is to determine the cancer's extent, called the stage. Your healthcare team uses the cancer staging test results to help create your treatment plan.

Staging tests include:

• Complete blood count (CBC). A CBC reports the numbers of different types of cells in the blood. A CBC shows whether your red blood cell count is low, called anemia. Anemia suggests that the cancer is causing blood loss. A high level of white blood cells is a sign of infection. Infection is a risk if a rectal cancer grows through the wall of the rectum.
• Blood tests to measure organ function. A chemistry panel is a blood test to measure levels of different chemicals in the blood. Worrying levels of some of these chemicals may suggest that cancer has spread to the liver. High levels of other chemicals could mean problems with other organs, such as the kidneys and liver.
• Carcinoembryonic antigen (CEA). Cancers sometimes produce substances called tumor markers. These tumor markers can be detected in blood. One such marker is CEA. CEA may be higher than usual in people with colorectal cancer. CEA testing can be helpful in monitoring your response to treatment.
• CT scan of the chest, abdomen and pelvis. This imaging test helps determine whether rectal cancer has spread to other organs, such as the liver or lungs.
• MRI of the pelvis. An MRI provides a detailed image of the muscles, organs and other tissues surrounding cancer in the rectum. An MRI also shows the lymph nodes near the rectum and different layers of tissue in the rectal wall more clearly than a CT does.
• Surgery. Surgery may be used in rectal cancer staging when doctors or other healthcare professionals need to confirm how far the cancer has spread, especially after treatment such as radiation or chemotherapy. By examining the tumor and nearby lymph nodes removed during surgery, they can determine the exact stage of the cancer, including whether it has spread beyond the rectum or to lymph nodes.

Rectal cancer stages

After a rectal cancer diagnosis, other tests might be needed to find out how far the cancer has spread. This is called staging. Knowing the stage of cancer is important because it helps your healthcare team create the most effective treatment plan.

Staging tests often include blood tests and imaging scans of the abdomen, pelvis and chest. These scans create pictures that show the location and the size of the rectal cancer. Sometimes imaging isn't enough, and surgery is needed to find out the stage of the cancer.

Staging terms

Rectal cancer is typically classified in five stages, but there is no stage 5 rectal cancer. The stages are 0, 1, 2, 3 and 4. Higher numbers mean more-advanced cancer. Earlier stages often mean the cancer is limited to the rectum, while later stages may involve spread to lymph nodes or distant organs.

To describe each stage in more detail, healthcare professionals commonly use the TNM system. The TNM system looks at three key factors:

• T. The size of the primary tumor.
• N. Whether the cancer has spread to nearby lymph nodes.
• M. Whether the cancer has spread to other parts of the body, called metastasis.

Staging can be complex, so if you're not sure what something means in your chart, ask your healthcare team to explain it in a way that makes sense to you.

Stage 0 rectal cancer

In stage 0, the earliest stage of rectal cancer, cancer cells are found only in the innermost layer of the rectum, called the mucosa. At this stage, the cells have not grown into deeper layers of the rectal wall. This stage also is referred to as carcinoma in situ.

If the cancerous area is small and accessible, doctors or other healthcare professionals may operate using a tool through the anus. This is called local excision. Local excision procedures include transanal excision (TAE) or transanal minimally invasive surgery (TAMIS). These procedures aim to completely remove the cancer while preserving rectal function. If the cancer is too large or poorly located for local excision, part of the rectum may need to be removed.

Stage 1 rectal cancer

In stage 1, the cancer has grown into the deeper layers of the rectal wall, but it has not spread to nearby lymph nodes or distant parts of the body. Because the cancer is still confined to the rectum, it is considered localized.

When stage 1 rectal cancer is found inside a polyp, local excision using transanal surgery may be the only treatment needed. If the cancer is considered high grade, meaning it's more likely to grow and spread quickly, a more extensive surgery may be recommended. Additional surgery or treatment also may be needed if the cancer is not completely removed or if the margins around the removed tissue are not clear of cancer cells.

In cases where the cancer is not in a polyp or is larger or deeper, a partial resection of the rectum may be performed. This procedure usually includes removal of nearby lymph nodes to check for microscopic spread.

Stage 2 rectal cancer

In stage 2 rectal cancer, the cancer has grown through the inner layers of the rectum and may have reached nearby tissues or organs. However, it has not spread to nearby lymph nodes or distant sites. Stage 2 rectal cancer is considered localized when it remains in the rectum It's considered regional if it has begun to involve nearby structures such as adjacent organs.

• Stage 2A. The cancer has reached the outer layers of the rectal wall but has not penetrated through them and has not spread to lymph nodes or distant organs.
• Stage 2B. The cancer has grown through the rectal wall into surrounding tissue but has not invaded nearby organs and has not spread to lymph nodes or distant sites.
• Stage 2C. The cancer has invaded nearby organs or structures such as the bladder, prostate, uterus or bone, but lymph nodes and distant organs are not affected.

Surgery to remove the affected portion of the rectum is often the first treatment. Procedures may include a low anterior resection (LAR) or abdominoperineal resection (APR) depending on the cancer's location and depth. Nearby lymph nodes also are removed during surgery to check for microscopic spread. Depending on the cancer's features, such as its depth, grade or closeness to other structures, chemotherapy or radiation may be recommended either before surgery or after surgery to reduce the risk of recurrence.

Stage 3 rectal cancer

In stage 3 rectal cancer, the tumor has spread to nearby lymph nodes but not to distant parts of the body. This is considered regional cancer, because it involves the local lymphatic system surrounding the rectum but not other organs.

• Stage 3A. The cancer has grown into the deeper layers of the rectum and has spread to 1 to 3 nearby lymph nodes. Or there are tumor deposits in tissues near the rectum without lymph node involvement but no distant metastasis.
• Stage 3B. The cancer has grown through the layer of muscle tissue in the rectal wall and may have reached perirectal tissues or even surrounding structures. It also has spread to 1 to 3 regional lymph nodes but not to distant sites.
• Stage 3C. The cancer has spread to 4 or more nearby lymph nodes, regardless of how far the tumor has grown within or beyond the rectum. Distant metastasis is still not present.

Stage 3 rectal cancer is typically treated with a combination of therapies. Most people receive chemotherapy and radiation before surgery to shrink the cancer, an approach called neoadjuvant therapy. This can be followed by surgical removal of the rectum and nearby lymph nodes. After surgery, chemotherapy may be recommended to reduce the risk of recurrence. In some people, rectal cancer may go away with chemotherapy and radiation alone, and surgery is not necessary.

Stage 4 rectal cancer

In stage 4 rectal cancer, the cancer has spread to distant parts of the body, such as the liver, lungs or the lining of the abdominal cavity, called the peritoneum. This is called metastatic or distant rectal cancer.

• Stage 4A. The cancer has spread to one distant organ, such as the liver or lungs, or to distant lymph nodes, but not to multiple locations.
• Stage 4B. The cancer has spread to more than one distant organ or distant set of lymph nodes.
• Stage 4C. The cancer has spread to distant parts of the peritoneum.

Treatment for stage 4 rectal cancer mainly relies on chemotherapy. Targeted therapy and immunotherapy may be recommended for people whose cancer cells have specific gene changes. Radiation can be used to relieve symptoms or temporarily shrink the cancer. Surgery can be considered in rare, specific situations.

Depending on your situation, you may be eligible to take part in a clinical trial. Ask your healthcare team if there are available options for your type of cancer.

How fast does rectal cancer spread?

Most rectal cancers begin as growths in the lining of the rectum, such as adenomas, which are a type of polyp. These polyps often grow slowly and may take many years to become cancerous. However, not all polyps turn into cancer.

Once rectal cancer develops, how quickly it grows or spreads depends on several factors. These include the type and grade of the cancer cells, whether the cancer has invaded deeper layers of the rectum, and your overall health and age. Some cancers stay localized for a while, while others may spread more quickly to nearby lymph nodes or distant organs such as the liver or lungs.

Looking ahead

Thanks to recent advancements in rectal cancer treatment, many people are living longer with better quality of life. Your experience with cancer is unique, and your care team is here to support you through each step. After treatment, regular follow-ups can help manage your health and monitor for any signs of recurrence.

Treatment

Rectal cancer is often curable, especially when found early. Even some cancers that have spread may be curable with the right treatment approach. Treatment may begin with surgery to remove the cancer. If the cancer grows larger or spreads to other parts of the body, treatment might start with medicine and radiation instead.

Your healthcare team considers many factors when creating a treatment plan. These factors may include your overall health, the type and stage of your cancer, and your preferences.

Surgery

Surgery to remove the cancer can be used alone or in combination with other treatments.

Procedures used for rectal cancer may include:

• Removing very small cancers from the inside of the rectum. Very small rectal cancers may be removed using a colonoscope or another specialized type of scope inserted through the anus. This procedure is called transanal local excision. Surgical tools can be passed through the scope to cut away the cancer and some of the healthy tissue around it.

  This procedure might be an option if your cancer is small and not likely to spread to nearby lymph nodes. If a lab exam of your cancer cells shows that they are aggressive or more likely to spread to the lymph nodes, additional surgery may be needed.

• Removing all or part of the rectum. Larger rectal cancers that are far enough away from the anus might be removed in a procedure that removes all or part of the rectum. This procedure is called low anterior resection. Nearby tissue and lymph nodes also are removed. This procedure preserves the anus so that waste can leave the body as it usually would.

  How the procedure is performed depends on the cancer's location. If cancer affects the upper portion of the rectum, that part of the rectum is removed. The colon is then attached to the remaining rectum. This is called colorectal anastomosis. All of the rectum may be removed if the cancer is in the lower portion of the rectum. Then the colon is shaped into a pouch and attached to the anus, called coloanal anastomosis.

• Removing the rectum and anus. For rectal cancers that are located near the anus, it might not be possible to remove the cancer completely without hurting the muscles that control bowel movements. In these situations, surgeons may recommend an operation called abdominoperineal resection, also known as APR. With APR, the rectum, anus and some of the colon are removed, as well as nearby tissue and lymph nodes.

  The surgeon creates an opening in the abdomen and attaches the remaining colon. This is called a colostomy. Waste leaves the body through the opening and collects in a bag that attaches to the abdomen.

Chemotherapy

Chemotherapy treats cancer with strong medicines. Chemotherapy medicines are typically used before or after surgery in people with rectal cancer. Chemotherapy is often combined with radiation therapy and used before an operation to shrink a large cancer so that it's easier to remove with surgery.

In people with advanced cancer that has spread beyond the rectum, chemotherapy is used to slow down the growth of cancer. This extends survival and helps relieve symptoms caused by the cancer.

Radiation therapy

Radiation therapy treats cancer with powerful energy beams. The energy can come from X-rays, protons or other sources. For rectal cancer, radiation therapy is most often done with a procedure called external beam radiation. During this treatment, you lie on a table while a machine moves around you. The machine directs radiation to precise points on your body.

In people with rectal cancer, radiation therapy is often combined with chemotherapy. It is usually used before surgery to shrink a cancer to make it easier to remove.

When surgery isn't an option, radiation therapy might be used to relieve symptoms, such as bleeding and pain.

Combined chemotherapy and radiation

Combining chemotherapy and radiation therapy may enhance the effectiveness of each treatment. Combined chemotherapy and radiation may be the only treatment you receive, or combined therapy can be used before surgery. Combining chemotherapy and radiation treatments may increase side effects.

Targeted therapy

Targeted therapy for cancer is a treatment that uses medicines that attack specific chemicals in the cancer cells. By blocking these chemicals, targeted treatments can cause cancer cells to die.

For rectal cancer, targeted therapy may be combined with chemotherapy for advanced cancers that can't be removed with surgery or for cancers that come back after treatment.

Some targeted therapies only work in people whose cancer cells have certain DNA changes. Your cancer cells may be tested in a lab to see if these medicines might help you.

Immunotherapy

Immunotherapy for cancer is a treatment with medicine that helps the body's immune system kill cancer cells. The immune system fights off diseases by attacking germs and other cells that shouldn't be in the body. Cancer cells survive by hiding from the immune system. Immunotherapy helps the immune system cells find and kill the cancer cells.

For rectal cancer, immunotherapy is sometimes used before or after surgery. It also may be used for advanced cancers that have spread to other parts of the body. Immunotherapy only works for a small number of people with rectal cancer. Special testing can determine if immunotherapy might work for you.

Palliative care

Palliative care is a special type of healthcare that helps you feel better when you have a serious illness. If you have cancer, palliative care can help relieve pain and other symptoms. A healthcare team that may include doctors, nurses and other specially trained health professionals provides palliative care. The care team's goal is to improve quality of life for you and your family.

Palliative care specialists work with you, your family and your care team. They provide an extra layer of support while you have cancer treatment. You can have palliative care at the same time you're getting strong cancer treatments, such as surgery, chemotherapy or radiation therapy.

The use of palliative care with other proper treatments can help people with cancer feel better and live longer.

Rectal cancer survival rates

The chance of being cured is high for people with early-stage rectal cancer. When the cancer is found in its early stages and hasn't spread to lymph nodes or distant organs, many people do very well with treatment. As the cancer grows deeper into the rectum or spreads to other parts of the body, the chance of a cure becomes lower.

Survival statistics

The U.S. National Cancer Institute groups rectal and colon cancers together when reporting survival statistics, referring to them collectively as colorectal cancer rates. To understand survival rates, experts study many people being treated for colorectal cancer and then report how many are living five or 10 years after their diagnosis.

Many people expect these colorectal cancer survival rates to be reported by numbered stages, from 0 to 4. But the U.S. National Cancer Institute reports survival rates by how far the cancer has spread. This is called summary staging, and the categories include localized, regional and distant colorectal cancer.

Localized colorectal cancer

Localized cancer is confined in the rectum and has not spread to nearby lymph nodes or distant parts of the body. Localized cancer is considered early-stage cancer and includes stages 0, 1 and most stage 2 colorectal cancers.

Survival rate for people with localized colorectal cancer

Age group	5-year survival rate	10-year survival rate
Under age 50	95.0%	91.4%
Age 50 and older	90.5%	85.3%

Regional colorectal cancer

Regional cancer means the cancer has spread beyond the rectal wall to nearby tissues or lymph nodes but not to distant parts of the body. This includes stage 3 rectal cancers and some stage 2 cancers, especially when the tumor has grown into nearby organs or structures.

Survival rate for people with regional colorectal cancer

Age group	5-year survival rate	10-year survival rate
Under age 50	79.6%	70.6%
Age 50 and older	72.3%	63.0%

Distant colorectal cancer

Distant cancer has spread to other parts of the body. The liver is the most common site. It also may spread to the lungs, distant lymph nodes, the inner lining of the abdominal cavity, called the peritoneum, or other parts of the body. Distant rectal cancer includes stage 4 cancer. Stage 4 also is called metastatic, late-stage or advanced cancer.

Survival rate for people with distant colorectal cancer

Age group	5-year survival rate	10-year survival rate
Under age 50	22.4%	14.5%
Age 50 and older	14.0%	9.0%

These survival rates are specific to people in the U.S. and may not be the same in other countries. For the most accurate information, ask your healthcare team for survival rates in your home country.

What you can do

Cancer survival rates might seem scary, but they vary widely. And the rates don't tell the whole story for each person. While there may be many things about your rectal cancer that you can't change, you are not powerless. There are many things you can do that may influence your outcome. By adopting a proactive approach, you can actively contribute to your well-being and possibly make a big difference in your personal prognosis.

Some factors you can't control include:

• Stage at diagnosis. Typically, the earlier the cancer is caught, the better the outcomes will be.
• Age. Older age at diagnosis is linked to lower survival rates.
• Genetic factors. A family history of colorectal cancer or certain inherited syndromes, such as familial adenomatous polyposis (FAP) and Lynch syndrome, can affect both risk and prognosis.
• Type of cancer cells. Some cancer cells tend to grow and spread more quickly. These are known as poorly differentiated or high-grade cancers.

Factors you can control include healthy habits, such as:

• Physical activity. Physically active people with rectal cancer reported improved survival rates compared with people who reported no activity. Being active also may help relieve cancer symptoms and treatment side effects. Talk with your healthcare team about the best activity level for your situation.
• Nutrition. According to the American Cancer Society, eating a diet rich in plant-based foods and fiber and avoiding processed foods and sugars may improve health outcomes.
• Smoking. Smoking is strongly linked to worse survival in all stages of rectal cancer. If you smoke, ask your care team about strategies to help you quit.
• Obesity. Excess body weight is linked to lower survival rates and a higher risk of recurrence in people with rectal cancer. Obesity also can increase treatment-related complications and make recovery more difficult.

For the best results, talk with your healthcare team before changing your health habits, especially during treatment. Your care team can start you on the right track and help you along the way.

Survival rates are improving

Keep in mind that survival statistics take five years to collect. The most recent survival rates include people who had rectal cancer treatment more than five years ago. These people may not have had access to the latest treatments. Over the last few decades, advances in diagnosis and treatment have continued to steadily improve survival rates and quality of life for people with rectal cancer. Ongoing developments in targeted therapies, immunotherapy and personalized medicine signal the potential for even stronger results moving forward.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Coping and support

With time, you'll find what helps you cope with the uncertainty and worry of a rectal cancer diagnosis. Until then, you may find it helps to:

Learn enough about rectal cancer to make decisions about your care

Ask your healthcare team about your cancer, including your test results, treatment options and, if you like, your prognosis. As you learn more about rectal cancer, you may become more confident in making treatment decisions.

Keep friends and family close

Keeping your close relationships strong can help you deal with rectal cancer. Friends and family can provide the practical support you may need, such as helping take care of your home if you're in the hospital. And they can serve as emotional support when you feel overwhelmed by having cancer.

Find someone to talk with

Find someone who is willing to listen to you talk about your hopes and worries. This may be a friend or family member. The concern and understanding of a counselor, medical social worker, clergy member or cancer support group also may be helpful.

Ask your healthcare team about support groups in your area. Other sources of information include the U.S. National Cancer Institute and the American Cancer Society.

Preparing for your appointment

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.

If your healthcare professional thinks you might have rectal cancer, you may be referred to a doctor who specializes in treating diseases and conditions of the digestive system, called a gastroenterologist. If a cancer diagnosis is made, you also may be referred to a doctor who specializes in treating cancer, called an oncologist.

Because appointments can be brief, it's a good idea to be prepared. Here's some information to help you get ready.

What you can do

• Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as restrict your diet.
• Write down symptoms you have, including any that may not seem related to the reason for which you scheduled the appointment.
• Write down key personal information, including major stresses or recent life changes.
• Make a list of all medicines, vitamins or supplements you're taking and the doses.
• Take a family member or friend along. Sometimes it can be very hard to remember all the information provided during an appointment. Someone who goes with you may remember something that you missed or forgot.
• Write down questions to ask your healthcare team.

Your time with your healthcare team is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important in case time runs out. For rectal cancer, some basic questions to ask include:

• In what part of the rectum is my cancer located?
• What is the stage of my rectal cancer?
• Has my rectal cancer spread to other parts of my body?
• Will I need more tests?
• What are the treatment options?
• How much does each treatment increase my chances of a cure?
• What are the potential side effects of each treatment?
• How will each treatment affect my daily life?
• Is there one treatment option you believe is the best?
• What would you recommend to a friend or family member in my situation?
• Should I see a specialist?
• Are there any brochures or other printed material that I can take with me? What websites do you recommend?
• What will determine whether I should plan for a follow-up visit?

Don't hesitate to ask other questions.

What to expect from your doctor

Be prepared to answer questions, such as:

• When did your symptoms begin?
• Have your symptoms been continuous or occasional?
• How severe are your symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, appears to worsen your symptoms?

Living with rectal cancer?

Connect with others like you for support and answers to your questions in the Colorectal Cancer support group on Mayo Clinic Connect, a patient community.

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