Anal cancer is a type of cancer that occurs in the anal canal, located at the end of the gastrointestinal tract. It is often confused with colorectal cancer, a cancer of the colon or rectum.
Even though it is a rare form of cancer, the number of cases is increasing considerably. While the average age of diagnosis is the early 60s, women are at a higher risk than women.
Most people with anal cancer receive chemotherapy and radiation as a means of treatment.
Anal Cancer Symptoms
Anal cancer is a serious condition and its symptoms may sometimes seem very general. However, anal cancer needs to be taken far more seriously and may some of these symptoms-
- Pain in the anal area
- Lumps around the anus, commonly mistaken as piles or haemorrhoids
- Changes in bowel movements i.e., diarrhoea and constipation or thinning of stools
- Jelly-like discharge from the anus
- Bloating
- Itching in the anal area
- Noticeable rectal bleeding
- Difficulty in controlling bowel movements
- Lower back pain as tumour presses on the vagina (Experienced by women)
- Vaginal dryness (Experienced by women)
Most of these symptoms are due to non-cancerous conditions like anal warts, anal fissures, haemorrhoids, etc which is why people may ignore them. It is best to have the symptoms checked so as to understand the main reason behind this.
Anal Cancer Risk Factors
Studies have linked a number of risk factors to anal cancer. The risk may be multiplied in the following cases-
- Human Papilloma Virus (HPV) - Most people with anal cancer have HPV, which is why the two are known to be closely related.
- Receptive anal intercourse- Men and women receiving anal intercourse are at a higher risk of developing anal cancer. HIV positive men who have anal intercourse with men are most likely to develop anal cancer.
- Multiple sexual partners- Having multiple sexual partner’s increases the risk of contracting HPV which leads to a higher risk of anal cancer.
- Weak Immune System- HIV positive patients who are taking medications after a transplant is at a higher risk of contracting anal cancer.
- Age- A popular pattern among anal cancer patients is that it is more likely to occur at old age.
- Smoking- Smokers are at a higher risk of having cancer than non-smokers.
- Benign and Lesions- Irritable bowel disease, fistulae, haemorrhoids or cicatrices are known to increase the risk of anal cancer.
- Other cancers- Women who already have vaginal or cervical cancer and men having penile cancer are at a higher risk of developing anal cancer.
Anal Cancer Causes
Anal cancer is developed when a genetic mutation turns normal, healthy cells to abnormal cells. Healthy cells grow and multiply at a fixed rate and eventually die at a set time. Abnormal cells, on the other hand, grow and multiply at a higher rate and do not die. This leads to an accumulation of abnormal cells to form a tumour.
The cancer cells may invade the nearby tissues separating from the initial tumour to spread elsewhere in the body which can be extremely dangerous.
The presence of human papillomavirus (HPV) also affects Anal cancer. There has been enough evidence of HPV being detected in a majority of anal cancers and is one of the most common causes of anal cancer.
Anal Cancer Diagnosis
Some of the tests and procedures that assist in the diagnosis of anal cancer are-
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Examination of the anal canal and rectum for abnormalities-
The digital rectum exam requires the doctor to insert a fully lubricated and gloved finger into the rectum. This is done to feel any unusual growth in the rectum.
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Visual inspection of the anal canal and rectum-
The doctor would use a lighted tube (anoscope) to inspect the rectum and anal canal for any unusual sighting.
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Ultrasound of the anal canal-
The doctor would first create a picture of the anal canal by inserting a thick thermometer like a probe into the anal canal and rectum. This emits high-energy sound waves that bounce off the organs and tissues to create a picture. The doctor would then evaluate the picture to identify any abnormality.
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A sample tissue for laboratory testing-
If the doctor finds any unusual area, he may take samples of the area, known as a biopsy, and send them for analysis. Doctors then determine whether the cells are cancerous by looking through under a microscope.
Once the diagnosis confirms anal cancer, the doctor may recommend a few other tests to determine the extent to which the cancer cells have spread. Some of the tests include-
- Computerized tomography (CT Scan)
- Magnetic Resonance Imaging (MRI)
- Position Emission Tomography (PET)
The doctor would then use this information to assign a stage to cancer. Depending on the cancer stage, the doctor would determine the right course of treatment for the patient.
Anal Cancer Treatment
Depending on how advanced the cancer is and what stage it is on, the doctor would decide a course of treatment.
Chemotherapy-
Chemotherapy is a treatment that involves the use of drugs or pill to cure the cancerous cells. The chemicals travel through the body and kill the rapidly growing cells, however, it also damages the healthy cells like those in the gastrointestinal tract and hair follicles. This may lead to a number of side effects like nausea, vomiting and hair loss.
Radiation Therapy-
Radiation therapy makes the use of high-power beans, i.e., X-rays and protons to kill cancer cells. The patient must lie down on the table and a large machine moves around him/ her so as to direct radiation beams to specific areas of the body targeting cancer. Radiation too may damage the healthy tissues resulting in skin redness and sores around the anal area.
Chemotherapy and radiation-
The treatment of anal cancer involves a combination of chemotherapy and radiation. The two enhance the chances of cure and enhance each other.
A combination of both increases the effectiveness of the treatment but also makes side effects more likely.
Surgery-
On the basis of the stage of cancer, the doctor may typically use different procedures.
Early Stage Anal Cancer-
Small and early stage anal cancers may be subject to removal through surgery. The doctor removes the tumour and a small amount of healthy tissue surrounding it during this procedure.
As the size of the tumour is small, doctors can remove early-stage cancers without posing much damage to the anal sphincter muscles surrounding the anal canal. This muscle is responsible for controlling bowel movements which is why doctors are keen to keep the muscles.
Last Stage Anal Cancer-
If the case is at almost last stage and cancer isn't responding well to other treatments like chemotherapy and radiation, then the other option will be another extensive operation. Known as the abdominoperineal resection or AP resection, the procedure involves removal of the anal canal, rectum and a portion of the colon. The surgeon then attaches the remaining portion of the colon to an opening in the abdomen for the waste to leave the body and collect in a colostomy bag.
While there are a number of treatment options, the chances of recovery depend largely on the size and location of the tumour and area to where cancer has spread.
Jun 01, 2019
May 30, 2018