Anal cancer is cancer or the growth of cells that are fast, uncontrollable, and malignant in the anus. Anal cancer is a type of cancer that is quite rare. Anal cancer can cause pain and bleeding in the anus.
The anus is a short tube at the end of the rectum and serves as a passageway for feces to pass. One of the diseases associated with anal cancer is HPV infection (human papillomavirus). Anal cancer has the possibility to be cured, especially if it is detected at an early stage and treated immediately.
Causes of Anal Cancer
Anal cancer is caused by genetic changes (mutations) in the cells of the anus that cause these cells to turn malignant. Abnormal anal cells grow quickly, uncontrollably, damage surrounding tissues, and spread to other parts of the body (metastasize).
Anal cancer is often associated with viral infections human papillomavirus (HPV). However, it does not mean that every person with HPV infection will experience anal cancer. Infection with the HPV virus will produce a protein that can inactivate tumor suppressor proteins in normal cells, so cells can grow uncontrollably.
Types of anal cancer
Based on the type of cell that turns malignant, anal cancer can be divided into several types, namely:
- Squamous cell carcinoma, which is cancer that starts in cells in the anal canal
- Adenocarcinoma, which is cancer that originates from the glands around the anus
- Basal cell carcinoma, which is cancer that originates in the cells of the surface of the anus and is very rare
In addition to anal cancer, benign tumors that develop into malignant (pre-cancerous) can also appear in the anus. The example is anal intraepithelial neoplasia (AIN) and anal squamous intraepithelial lesions (SILs).
Anal Cancer Risk Factors
There are several factors that can make a person more at risk of developing anal cancer, including:
- Over 50 years old
- Frequently changing sexual partners
- Often the recipient of anal sex
- Have a history of cervical cancer
- Having warts on the anus which can be caused by HPV infection
- Have a weakened immune system due to having AIDS, taking immunosuppressant drugs, or undergoing chemotherapy
- Have a smoking habit
Symptoms of Anal Cancer
In some people, anal cancer may not cause any symptoms (asymptomatic) at first. However, in most people with anal cancer, symptoms can appear in the form of:
- Bleeding from the rectum or anus
- Pain in the anus
- Lumps or swelling in the anus
- Itching in the anus and discharge such as mucus or pus from the anus
- Changes in bowel patterns
When to go to the doctor
Immediately consult a doctor if you experience the complaints or symptoms mentioned above, especially if you have conditions that can increase the risk of developing anal cancer.
Anal Cancer Diagnosis
To diagnose anal cancer, the doctor will ask about the symptoms and complaints experienced by the patient, as well as perform an examination of the rectum and anus to see whether there are lumps that could indicate cancer.
The examination can be performed using a digital rectal technique and continued with the aid of an anusoscope. An anusoscope is a funnel-like instrument used to see the anus and rectum more clearly.
To confirm the diagnosis, the doctor will also perform a number of supporting examinations as follows:
- endoscope, to see the rectum and anus, and to detect the presence or absence of abnormally growing tissue in the digestive tract
- Transrectal ultrasound, to see the growing tissue in the anus and surrounding areas
- Biopsy by taking a sample of anal tissue, to determine the type of cells and tissues that are growing
- Scans with CT scans, MRIs, and PET scans to determine the location, size, and stage of the patient's cancer
Anal cancer stage
Based on the TNM classification (tumor, nodule, and metastases), anal cancer can be divided into 4 stages. Here is the explanation:
- Stage 0: Cancer is found only in the anal mucosa. Stage 0 is also called high-grade squamous intraepithelial lesion (HSIL).
- Stage I: Anal cancer measuring 2 cm, no spread to lymph nodes, no spread to other tissues or organs
- Stage 2: Anal cancer >2 cm and has not spread to other organs
- Stage 3: Anal cancer has spread to lymph nodes around the anus or to organs around the anus, such as the bladder, urinary tract (urethra), and vagina
- Stage 4: Anal cancer has spread to lymph nodes and other organs further from the anus, such as the liver or lungs
Anal Cancer Treatment
Treatment of anal cancer will be tailored to the stage of cancer and the patient's general condition. Below are some of the methods used for the treatment of anal cancer:
1. Combination of chemotherapy and radiotherapy
To increase the effectiveness and success of cancer treatment, doctors usually use a combination of chemotherapy and radiation.
Chemotherapy is done by giving drugs to kill cancer cells. However, this drug can also damage healthy cells, such as cells in the digestive tract and hair follicles.
Radiotherapy is done by emitting X-rays and protons to kill cancer cells.
2. Operation
In the early stages of anal cancer, the doctor will perform surgery to remove the anal cancer. If the anal cancer is small, the surgical procedure will not damage too much of the surrounding tissue, including the anal sphincter muscle, which regulates bowel movements.
To treat advanced anal cancer, doctors can perform procedures abdominoperineal resection. In this procedure, the doctor will remove the anal canal, rectum, and part of the large intestine. Next, the rest of the large intestine will be connected to the abdominal wall that has been perforated (stoma), so that feces can still be expelled.
3. Immunotherapy
Immunotherapy aims to increase the patient's immune system to fight cancer cells. Immunotherapy is usually used to treat patients with advanced anal cancer.
4. Therapy palliative or supportive therapy
This therapy is given to relieve the symptoms of anal cancer and relieve the side effects of cancer treatment. This therapy will be done in conjunction with other cancer treatment methods.
Anal cancer rarely spreads (metastasizes) to other parts of the body. When cancer cells have spread to the liver and other organs, anal cancer will be difficult to treat.
Anal Cancer Prevention
Until now, anal cancer can not be prevented. However, the following steps can be taken to reduce the risk of anal cancer:
- Get the HPV vaccine when you're a teenager or adult
- Do not change sexual partners
- No anal sex
- Undergo screening for anal cancer if you have risk factors
- Quit smoking