Table of ContentsView AllTable of ContentsStagesRectal vs. Colon CancerStaging and PrognosisAfter DiagnosisStage of Recurrent Rectal Cancer
Table of ContentsView All
View All
Table of Contents
Stages
Rectal vs. Colon Cancer
Staging and Prognosis
After Diagnosis
Stage of Recurrent Rectal Cancer
Rectal cancer is cancer that originates in the tissues of the rectum. This type of cancer is sometimes referred to as colorectal cancer.The colon, rectum, and anal canal are all parts of the digestive system. The rectum is situated between the colon and the anus. Cancer can originate in any of these areas.
The place where cancer cells start to form and grow will determine the type of cancer you have. Colon cancer and rectal cancer are both forms ofcolorectal cancer.Anal canceris not.
Like most cancers, rectal cancer isclassified in stages from 0 to 4. The stage indicates the size and type of tumor and the amount of spread (metastasis) that has occurred.
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Staging System
Rectal cancertypically originates inpolyps(growths) within the inner lining of the rectum. Polyps are common in this part of the body and don’t always turn into cancer. The polyps most likely to become cancerous are referred to as villous adenomas.
The American Joint Committee on Cancer (AJCC) TNM system is usually used to stage rectal cancer. This system uses a combination of three indicators to determine what stage the cancer is in:
Rectal cancer is staged from stage 0 to stage 4 and includes several substages:
Stage 0 (Carcinoma in situ)
Stage 0 TNM characteristics:
Carcinoma in situ is sometimes referred to as precancer. When rectal cancer is in stage 0, abnormal cells have been found only in the innermost layer (mucosa) of the rectum wall.These cells may have the potential to become malignant (cancerous) but are not yet considered cancer.
Stage 1
Stage 1 TNM characteristics:
When rectal cancer is in stage 1, cancerous cells have spread out from the mucosa into the surrounding tissue layer (submucosa) or into the muscle layer of the rectum wall.
Stage 2a
Stage 2a TNM:
Stage 2 rectal cancer is further broken down into symptom groups 2a, 2b, and 2c. In stage 2a, cancerous cells have spread into the outermost rectum wall layer (serosa).At this point in the cancer’s progression, there is no spread outside of the rectum wall.
Stage 2b
Stage 2b TNM:
In this stage, cancer cells have spread out of the serosa and into the layer of tissue that lines the outsides of the organs within the abdomen (visceral peritoneum).These organs include the liver, bladder, and spleen. The cancer has not penetrated inside the organs.
Stage 2c
Stage 2c TNM:
Stage 3a
Stage 3a TNM:
Or:
Stage 3 rectal cancer is further broken down into symptom groups 3a, 3b, and 3c. In stage 3a, cancer has continued to spread in one of two ways:
Stage 3b
Stage 3b TNM:
Stage 3b rectal cancer indicates spread in one of three patterns:
Stage 3c
Stage 3c TNM:
Stage 3c rectal cancer indicates spread in one of three patterns:
Stage 4a
Stage 4a TNM:
Stage 4 rectal cancer is also referred to as metastatic rectal cancer. Stage 4 is further broken down into symptom groups 4a, 4b, and 4c.
In stage 4a, rectal cancer has metastasized (spread) to one distant organ or part of the body. Common sites for metastasis include the liver,prostate, lungs, or distant lymph nodes.
Stage 4b
Stage 4b TNM:
In stage 4b, rectal cancer has spread to more than one distant organ or area of the body.
Stage 4c
Stage 4c TNM:
In stage 4c, rectal cancer has spread to the abdominal wall lining (peritoneum). It may also have spread to other distant organs or parts of the body.
Tumor Characteristics in Rectal vs. Colon Cancer
Thedifferences between rectal and colon cancerstart with their point of origin.
The large intestine (large bowel) is comprised of the colon and rectum. Colon cancer can originate in any part of the colon, which is comprised of four sections:
The rectum, where rectal cancer originates, is located below the sigmoid colon.
Rectal cancer tumors and colon cancer tumors usually originate from mutations that occur in polyps.
Because they’re both part of the large intestine, the rectum and colon are housed within a wall that contains many layers. For that reason, rectal cancer tumors and colon cancer tumors share many of the same characteristics and symptoms.
Most of the rectum lacks the protective outer layer (serosa) that surrounds the entire colon.For this reason, rectal cancer tumors may spread more rapidly or aggressively than colon cancer tumors.
Common metastatic sites for rectal cancer tumors are the liver, brain, lungs, and peritoneum.Colon cancer rarely spreads to the brain but may spread to any of these other sites.
The stage and spread of the cancer will influence your prognosis. Even though the stage is important, it is just one indicator.
Cutting-edge treatments, such as the use ofimmunotherapy(treatments that use the immune system) andclinical trials(testing new treatments or treatment regimens), have changed the prognosis landscape.Your experience may be very different from the experiences of others who have rectal cancer in the same stage.
Tumor grade will also affect your prognosis. Well-differentiated tumors contain tissues that resemble normal tissues. These types of tumors tend to grow and spread more slowly than poorly differentiated or undifferentiated cancer cells do.
Other factors that can impact your prognosis include age, sex, and overall health.
Does Treatment Cure Rectal Cancer?
Rectal cancer is a potentially life-threatening condition that is curable when caught early.
The five-year relative survival rates for rectal cancer are:
Keep in mind that survival rates are only estimates. They’re based on the experiences of people diagnosed five or more years earlier, and they don’t take new treatment innovations into account.
Next Steps With Diagnosed Rectal Cancer
If you or a loved one has been diagnosed with rectal cancer, you will work with a specialist on a treatment plan. The stage of the cancer and other factors, including your personal preferences for treatment, will be taken into account.
If the cancer is in stage 0 or stage 1, surgical removal of the tumor will be recommended. This procedure is referred to as a polypectomy. If cancerous cells are found along the edges of the tumor, more extensive surgery may be required.
Rectal cancer in later stages requires a different treatment protocol. Chemotherapy, radiation, and surgery are often combined to treat rectal cancer in stages 2, 3, and 4. The extent of the spread and tumor grade will determine which treatments are used and in what order.
Some treatments for rectal cancer produce short-term or long-term side effects. If you’re undergoing chemotherapy or radiation treatment, you may experience short-term nausea, fatigue, and other symptoms.
Some treatments produce side effects that are challenging and require a learning curve. For example, if you have a surgicalileostomy, you’ll have a stoma (an opening for stool to pass through the abdomen and be collected in an appliance) on either a temporary or permanent basis.
Your cancer team will provide you with tools that can help you adjust and thrive, even if you have a “new normal.”
Rectal cancer that returns after treatment is referred to as recurrent rectal cancer. If the cancer returns, it may be localized, or in distant organs or tissues. The location of the cancer will determine your treatment.
Cancer that returns usually gets the same stage number you received when you were first diagnosed. In some instances, a restaging number may be given, although this is uncommon.
Summary
Rectal cancer originates in the tissues of the rectum. Because the colon and rectum are both parts of the large bowel, cancer of the colon or rectum is sometimes referred to as colorectal cancer.
Rectal cancer is staged from 0 to 4, with several substages. Cancer stage and other factors, such as tumor grade, will determine your treatment and prognosis. Rectal cancer is curable when caught early.
14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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