Ans. : Anal cancer is found in or on the anus. The anus is part of the gastrointestinal tract and is the opening at the end of the large intestine, below the rectum, where bowel movements leave the body. The anus is made up of different types of cells, and each type can become cancerous. Therefore, there are several different types of anal cancer:
* Squamous cell carcinoma is the most common type of anal cancer. This cancer begins in the outer lining of the anal canal.
* Cloacogenic carcinoma accounts for about one-quarter of all anal cancers. This cancer arises between the outer part of the anus and the lower part of the rectum. Cloacogenic cell cancer likely starts from similar cells as squamous cell cancer and is treated similarly.
* Adenocarcinoma arises from the glands that make mucous, located under the anal lining.
* Basal cell carcinoma is a type of skin cancer that can appear in the perianal (around the anus) skin.
* Melanoma begins in cells in the skin or anal lining that darken the skin.
A tumor of the anus can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other areas of the body). There are also growths that can occur in or around the anus, such as polyps or warts. While these growths are not cancerous, some may become cancerous over time.
Ans. : Risk Factors and Prevention
A risk factor is anything that increases a person’s chance of developing cancer. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and communicating them to your doctor may help you make more informed lifestyle and health-care choices.
The following factors may raise a person’s risk of developing anal cancer:
Human papillomavirus (HPV) infection : HPV causes bumps on the skin around the anus commonly called venereal warts. There are different types or strains of HPV, and some strains are more strongly associated with anal cancer than others. HPV is most often spread through sexual contact, particularly anal intercourse. People with many sex partners have an increased risk of contracting HPV.
Age : Most cases of anal cancer are diagnosed in people between 50 and 80.
Frequent anal irritation. Frequent anal redness, swelling, and soreness may increase the risk of developing anal cancer.
Anal fistula : An anal fistula is an abnormal tunnel between the anal canal and the outer skin of the anus that often drains pus or liquid, which can soil or stain clothing. An anal fistula may irritate the outer tissues or cause discomfort. An anal fistula may increase the risk of developing anal cancer.
Cigarette smoking : Cigarettes can cause harm throughout the body, because chemicals from cigarettes can enter the bloodstream and affect nearly every organ and tissue in the body. Smokers are about eight times more likely to develop anal cancer than nonsmokers.
Lowered immunity : People with diseases or conditions affecting the immune system, such as HIV or organ transplantation, and people who take immunosuppressive drugs that make the immune system less able to fight disease, are more likely to develop anal cancer.
Even though some people who have no risk factors develop anal cancer, there are ways to prevent or reduce your risk of developing anal cancer.
* Avoid anal sexual intercourse, which carries an increased risk of HPV and HIV infection.
* Limit the number of sex partners, because having many partners increases the risk of HPV and HIV infection.
* Use a condom. However, even though condoms can protect against HIV, they cannot fully protect against HPV.
* Stop smoking.
Anal cancer screening
Anal cytology is a test being developed that doctors can use for people who have a high risk of contracting a sexually transmitted disease (STD) such as HPV and HIV. The test is similar to a Pap test, which looks for cervical cancer, except this test looks for anal cancer. The doctor can swab the anal lining and look at the cells on the swab under a microscope to find early cellular changes that might lead to cancer or may diagnose cancer from this swab. Some doctors are advocating the routine use of this test for men who have HIV and who have sex with men and for other people who are at high risk for developing anal cancer.
Ans. : People with anal cancer may experience the following symptoms. Sometimes, people with anal cancer do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not cancer. If you are concerned about a symptom on this list, please talk with your doctor.
* Bleeding from the anal area
* Pain or pressure in the anal area
* Itching or discharge from the anus
* A lump or swelling near the anus
* A change in bowel habits or change in the diameter of the stool
Ans. : Staging :
Staging is a way of describing a cancer, such as where it is located, if or where it has spread, and if it is affecting the functions of other organs in the body. Doctors use diagnostic tests to determine the cancer’s stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient’s prognosis (chance of recovery). There are different stage descriptions for different types of cancers.
One tool that doctors use to describe the stage is the TNM system. This system uses three criteria to judge the stage of the cancer: the tumor itself, the lymph nodes around the tumor, and if the tumor has spread to other parts of the body. The results are combined to determine the stage of cancer for each person. There are five stages: stage 0 (zero) and stages I through IV (one through four). The stage provides a common way of describing the cancer, so doctors can work together to plan the best treatments.
TNM is an abbreviation for tumor (T), node (N), and metastasis (M). Doctors look at these three factors to determine the stage of cancer:
* How large is the primary tumor and where is it located? (Tumor, T)
* Has the tumor spread to the lymph nodes? (Node, N)
* Has the cancer metastasized (spread) to other parts of the body? (Metastasis, M)
Tumor : Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe the size and location of the tumor. Some stages are also divided into smaller groups that help describe the tumor in even more detail. Specific tumor stage information is listed below:
TX: The primary tumor cannot be evaluated.
T0: There is no tumor.
Tis: Refers to carcinoma in situ (which is very early cancer that has not spread.)
T1: The tumor is no larger than 2 centimeters (cm).
T2: The tumor is larger than 2 cm, but not larger than 5 cm.
T3: The tumor is larger than 5 cm.
T4: The tumor has invaded other organs, such as the vagina, urethra, or bladder.
Node : The “N” in the TNM staging system stands for lymph nodes, the tiny, bean-shaped organs that help fight infection. Lymph nodes near the anus are called regional lymph nodes. Lymph nodes in other parts of the body are called distant lymph nodes.
NX: Regional lymph nodes cannot be evaluated.
N0 (N plus zero): There is no regional lymph node metastasis.
N1: Cancer had spread to the perirectal (around the rectum) lymph nodes.
N2: Cancer has spread to the internal iliac (pelvic) and/or the inguinal lymph nodes (lymph nodes in the groin just under the skin surface) on the same side of the body.
N3: Cancer had spread to the perirectal and inguinal lymph nodes and/or the internal iliac and/or inguinal lymph nodes on both sides of the body.
Distant metastasis : The “M” in the TNM system indicates whether the cancer has spread to other parts of the body.
MX: Distant metastasis cannot be evaluated.
M0 (M plus zero): There is no distant metastasis.
M1: There is metastasis to other parts of the body.
Cancer stage grouping :
Doctors assign the stage of the cancer by combining the T, N, and M classifications.
Stage 0: Abnormal cells are in the first layer of the lining of the anus only. The abnormal cells may become cancer. This stage is also called carcinoma in situ (Tis, N0, M0).
Stage I: The tumor is no larger than 2 cm with no spread to lymph nodes or other parts of the body (T1, N0, M0).
Stage II: The tumor is larger than 2 cm with no spread to lymph nodes or other parts of the body (T2 or T3, N0, M0).
Stage IIIA: The tumor may be any size and has spread to either nearby lymph nodes or to organs, such as the vagina, urethra, and bladder (T1, T2, T3; N1, M0; or T4, N0, M0).
Stage IIIB: The tumor may be any size and has spread to nearby lymph nodes or organs; lymph nodes in the pelvis and/or groin; or to lymph nodes near the rectum, in the groin and/or on both sides of the pelvis or groin (T4, N1, M0; or Any T, N2 or N3, M0).
Stage IV: The tumor may be any size and has spread to lymph nodes and to distant parts of the body (Any T, Any N, M1).
Recurrent: Recurrent cancer is cancer that comes back after treatment.
Histologic grade (G). In addition to the TNM system, doctors may also assign a histologic grade to the cancer. Histologic grade indicates how closely the cancer cells resemble normal tissue under a microscope. A tumor's grade is described using the letter “G” and a number.
GX: The tumor grade cannot be identified.
G1: Describes cells that look more like normal tissue cells (well differentiated).
G2: The cells are somewhat different from normal cells (moderately differentiated).
G3: The cells do not look like normal cells (poorly differentiated).
G4: Describes tumor cells that barely resemble normal cells (undifferentiated).