Anal cancer is not quite as prevalent as other forms of cancer, however, it’s estimated that roughly 8,000 cases of anal cancer are diagnosed each year and that just over 1,000 deaths are caused by this form of cancer every year. Anal cancer is not to be confused with colorectal or colon cancer, which is a cancer of the colon and rectum or just the colon, respectively. Read on to learn more about what anal cancer is and if it’s possible to prevent it—and what forms of treatment are used for those who are diagnosed. 

What Is Anal Cancer?


Unlike colon cancer, which is cancer of the colon, anal cancer is a malignancy that affects only the anus, the opening at the end of the rectum. When doctors are able to detect anal cancer in its early stages, it is one of the more treatable cancers. However, if it is not detected early, like other forms of cancer, it can spread to other organs and metastasize. Anal cancer can affect both men and women. In those under 35, anal cancer is more common in men. In those over age 50, anal cancer is more common in women. Looking at the male population alone, anal cancer is six times more common in single men than unmarried men. There is a strong correlation between receptive anal intercourse and the prevalence of anal cancer. Typically, across all populations, the average age for diagnosis is around age 60 or later. 

What Causes Anal Cancer?


There are certain risk factors for anal cancers, but the actual cause of anal cancer occurs as a result of tumor growth. Depending on where the tumor is located, anal cancer can be divided into two distinct types: squamous cell cancer and adenocarcinoma. 

  • Squamous cell cancer occurs in the anal canal that connects the outside of the body with the rectum. The lining of the anal canal is comprised of squamous cells. This is the most common type of anal cancer, and most anal cancers are diagnosed as squamous cell carcinoma. Bowen’s disease is a form of squamous cell carcinoma, but it is known as squamous cell carcinoma in situ. This means that cancer has not yet penetrated deeper layers of the anal canal. 
  • Adenocarcinoma occurs in what is known as the transitional zone. This is the area where the anus connects with the rectum. While squamous cells are also located here, there is a wealth of glandular cells. The function of these types of cells is to produce mucus to help bowel movements pass through the anal canal. However, tumors can develop here, which may develop into adenocarcinoma (cancer cells). This type of anal cancer is rare, making up only 3 to 9 percent of anal cancer cases. 
  • Basal cell carcinoma is an extremely rare form of skin cancer that may be diagnosed as anal cancer. This type of cancer occurs from sun exposure. 

Benign tumors can also occur in the anus. While your physician will want to evaluate these on a regular basis, there is no cause for immediate alarm. There are also precancerous conditions, such as anal intraepithelial neoplasia (AIN) and anal squamous intraepithelial neoplasia (ASIL). If benign tumors become malignant over time, they can turn into these conditions. 

What Are the Symptoms of Anal Cancer?


The beginnings of anal cancer can often look like hemorrhoids. Because there are many over-the-counter treatments for hemorrhoids, anal cancer could likely be missed if the patient continues to treat what they believe are hemorrhoids. 

One of the first major symptoms of anal cancer is bleeding from the rectum and anus. The other primary symptom is anal itching. These two symptoms are also prevalent in hemorrhoids, so before you treat yourself with over-the-counter medications, it’s best to be evaluated by a physician just to be sure. It’s estimated that 1 in 500 people will be diagnosed with this form of cancer. 

Other common symptoms of early anal cancer include:

  • Changes in the anus 
  • Pain or pressure in the anus or rectum
  • A noticeable lump near the anus
  • Changes in bowel habits
  • Anal discharge
  • Swollen lymph nodes in the anal area or groin
  • Narrow bowel movements
  • A feeling of fullness around the anus

If you’re experiencing one or more of these symptoms for more than several days, especially anal bleeding and/or itching, it’s a good idea to let your physician know. Many of these symptoms can also be anal tearing, hemorrhoids, or anal warts, but a doctor can properly diagnose the problem and offer the best course of action. 

Risk Factors and Prevention of Anal Cancer


There are definite risk factors when it comes to the development of anal cancer, and some patients are more at risk than others. One of the most prevalent risk factors for anal cancer is human papillomavirus (HPV). This is designated as the root cause of up to 91 percent of anal cancers. Human papillomavirus is also linked with certain other types of cancers, such as cervical cancer. 

Another risk factor for anal cancer is a weakened immune system, which puts those with the human immunodeficiency virus (HIV) at risk because of their weakened immune system. However, any patient that is immunocompromised is at greater risk of contracting anal cancer. 

Having receptive anal intercourse and multiple partners puts a patient at a stronger risk for contracting this form of cancer. Also, because HIV and HPV are spread through sexual intercourse, this compounds the risk. It is suggested that partners wear a condom at all times to lessen the risk of infection and anal cancer. 

Smokers, even those who have quit, and those over 60 are much more likely to develop anal cancer. The development of anal cancer is much less prevalent in those under the age of 35. 

To prevent anal cancer, it’s imperative always to practice safe sex, even if you are familiar with your partner. This includes wearing condoms and getting tested regularly for HPV, HIV, and other sexually transmitted diseases.

Smokers are urged to stop smoking. Even though smokers who have quit are at risk for cancer development, the risk is much less. 

Women and men between the ages of 9 and 26 can also receive the human papillomavirus vaccine, which can help prevent HPV, and in turn, anal cancer.

How Is Anal Cancer Treated?


Cancer treatment for this type of cancer depends on what stage the disease is in. More specifically, it depends on the cancer grade and the type of anal cancer, the person’s age and overall health, whether the cancer has spread or not, and the actual size of the tumor. The most common options are radiation therapy, chemotherapy, and surgery, although these may come with unwanted side effects.

There are two types of surgeries associated with anal cancer: resection and abdominoperineal resection. In simple resection, only the tumor is removed from the anus. This is a common procedure for small tumors that have not spread to other areas of the anal canal or rectum. Abdominoperineal resection is a more exhaustive procedure that removes the tumor, anus, rectum, and a section of the bowel. This type of surgery is necessary if the cancer has spread. Post-surgery, the patient will need to be fitted with a colostomy, which brings bowel movements to the outside of the body.

Radiation therapy uses rays to destroy cancer cells. There is both external and internal radiation therapy, and both come with unwanted side effects, such as extreme nausea and fatigue. 

Chemotherapy is slightly different, as it uses medical injection to try to kill cancer cells as compared to the energy rays used in radiation therapy. However, chemotherapy comes with many of the same adverse side effects. In addition to nausea and fatigue, patients may experience sexual dysfunction, bladder problems, anal inflammation, and a higher risk of blood clots in the legs. 

It is crucial to catch anal cancer early. Once you reach a certain age, your doctor will want to perform a rectal examination as part of your yearly physical, or your OB/GYN may want to perform one when you have a Pap smear appointment. If tumors are detected, a biopsy can be performed to determine if they are benign or malignant. If you need more information on anal cancer or would like to be seen for an evaluation, schedule an appointment at Carolina Digestive Health Associates today. Our eight office locations are convenient for every patient, and our caring and experienced staff can help reduce your anxiety, allowing you to feel more comfortable.