Overview
Anal cancer is a type of cancer that occurs in the anus. The anus is the part of the gastrointestinal tract, which is about 1-1/2 inches long and connects the rectum to the outside of the body. It also allows the solid waste to pass from the body. Anal cancer occurs when there is an uncontrollable growth of the cells, resulting in tumour formation.
A tumour can be cancerous or benign. A cancerous tumour is malignant and spreads to other parts of the body, while the benign tumour grows but does not spread. Anal cancer is uncommon and can be treated with a combination of treatments.
There are different types of anal cancer that are based on the type of cell where cancer begins, including:
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Squamous Cell Carcinoma:
The anal canal is made up of squamous cells. So, when there is rapid growth in the squamous cells. This is one of the most common types of anal cancer that begins in the outer lining of the anal canal.
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Cloacogenic Carcinoma
This type of anal cancer develops between the outer part of the anus and the lower part of the rectum.
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Basal Cell Carcinoma
This is a rare type of anal skin cancer that affects the skin exposed to the sun.
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Melanoma
This is a type of skin cancer that occurs in the pigment-producing cells found in the skin or anal lining.
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Adenocarcinoma
This is a rare anal cancer that develops in the glandular cells in the anal canal. The glandular cell produce mucus in the anal canal.
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Squamous Cell Carcinoma in Situ
Also known as Bowen's disease, this is a kind of skin cancer that affects the anal surface.
Common symptoms of anal cancer are as follows:
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Anal bleeding
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Pain around the anus
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Change in bowel habits
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Thin stool
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Discharge from the anus or itching
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Swelling or lump near the anus
The exact cause of anal cancer is not known at the moment. However, researchers have found out that it appears when abnormal cells grow. The cells might develop a mutation in the DNA and grow out of control, causing a tumour.
The tumour can invade and destroy normal body tissues, and they may also break away and spread through the body. Moreover, anal cancer is also closely related to sexually-transmitted infections like HPV or HIV. HPV is one of the most common causes of anal cancers.
Anal cancer has different stages. The range starts from Stage 0 and goes to Stage IV:
Stage 0: This stage is used to denote that the abnormal cells are found in the innermost layer of the anus. These cells may become cancer, and the stage is also called high-grade squamous intraepithelial lesion (HSIL)
Stage I: The stage denotes that the tumour is 2 centimeters or smaller in size.
Stage II: In this stage, the tumour is more significant than 2 centimeters and has not spread to the lymph nodes or other body parts.
Stage III: In this stage, cancer spreads to lymph nodes and nearby organs. Stage III can be further classified as Stage IIIA, Stage IIIB, and Stage IIIC. In stage IIIA, cancer spreads to the anus or groin. In stage IIIB, cancer spreads to the bladder, urethra, or vagina. Stage IIIC denotes that cancer has spread to nearby organs.
Stage IV: This is the most aggressive stage where cancer has spread to the lymph nodes or has spread to distant parts of the body.
Depending upon the stages of anal cancer, the doctor may recommend the following treatment:
If anal cancer is diagnosed early, the doctor may advise chemotherapy or radiation or a combination of both.
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Radiation Therapy
Radiation therapy uses X-rays and protons to kill the cancer cells present in the body. During this therapy, the patient is laid down on a table. Then X ray beams are directed to the specific points on the body. The length of radiation therapy varies with the stages of anal cancer.
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Chemotherapy
This treatment is done with the help of chemo drugs to destroy cancerous cells in the body. In most cases, there is a combination of several chemotherapy drugs. The chemo drugs are given intravenously.
If the anal cancer is in advanced stages and other treatments are ineffective, the doctor may recommend surgery. These may include:
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Abdominoperineal resection
In this surgical procedure, the surgeon removes the anus, rectum, and a section of the bowel. The surgery begins with the surgeon making an incision in the abdomen and another around the anus to remove the affected organs. The surgeon may also remove the nearby lymph nodes in the groin area in some cases. The abdominoperineal resection is followed by permanent colostomy.
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Colostomy
The surgical procedure involves creating a hole in the abdomen and pulling one end of the colon through it. The surgeon makes an incision in the abdomen and pulls the colon. The surgeon then attaches a colostomy bag to collect the stool.
Several risk factors may increase the chances of getting anal cancer. These include:
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Human Papillomavirus Infection (HPV)
Infection by HPV is one of the most critical risk factors for developing anal cancer. Most squamous cell carcinoma anal cancers are directly linked to HPV infection.
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Smoking
Smoking is also said to increase the risk of anal cancer. It has been found that people who smoke are more likely to have anal cancer compared to those who don't.
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Other cancers
People suffering from different types of cancers in the abdominal area are also at high risk of developing anal cancer. Females with cervical cancer or vaginal cancer and males with penile cancer are more likely.
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HIV Infection
People with HIV (Human immunodeficiency virus) are much more likely to get anal cancer than those not infected with this virus.
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Weak immunity
Those with weaker immune systems are more prone to develop anal cancer. Moreover, those with suppressed immune systems are also likely to be affected by anal cancer.
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Sexual activity
Receptive anal sex or having multiple sex partners increases the risk of developing anal cancer.
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Gender and Race
It has been found that anal cancer is more common in white women and African men.
There's no guaranteed way to prevent anal cancer, but there are some ways to reduce the risk of getting it:
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Use Protection
Practicing safe sex can help prevent infections like HIV and HPV. It also reduces the risk of anal cancer.
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Stop smoking
One of the best ways to prevent anal cancer is quitting smoking.
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Get Proper Vaccines
One should get a proper vaccination for the HPV virus, one of the root causes of anal cancer.
Patients will be in intensive care after anal cancer treatments. These include:
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Follow-up care, which can last for at least two years
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Frequent follow-up exams and tests at least for several years to look for signs of bladder cancer or side-effects of the treatments
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Regular visits to psychologists, recreation therapists, dietitians, and more for a speedy recovery
The outlook for a person with anal cancer depends on the stage it was diagnosed. Those diagnosed at an early stage have a better chance than those diagnosed at a later stage.