Anal Cancer: Causes, Symptoms and Treatment

Anal Cancer

Overview and Facts about Anal Cancer

Anal cancer is a disease that is characterized by the growth of malignant or cancerous tissue within the anus. The anus is located at the very end of the large intestine below the rectum and is partially comprised of intestinal tissue.

The anus plays an important anatomical role in the body’s digestive health; once digestion is complete, solid waste in the form of stool exits the body through the anal canal with help from two ring-shaped muscles called sphincter muscles. The anal canal is a one-inch opening located between the rectum and the anus. It is important to note that cancerous growths located on the outside of the anus, the perianal area, are not anal cancer growths but rather skin cancer growths.

The location of cancerous anal tissue allows for the classification of anal cancer into two distinct types: anal canal cancers and anal margin cancers.

Symptoms and Signs of Anal Cancer

Signs and symptoms of anal cancer are often uncomfortable and extremely noticeable for those affected. Over time and without treatment, these symptoms may worsen or become more persistent.

Signs and symptoms of anal cancer:

  • Noticeable changes in bowel habits, such as changes in the frequency of bowel movements
  • Itching, inflammation, pain, burning, or bleeding around the anus or rectum
  • Leakage of fluid or mucous discharge from the anus
  • Lumps felt on or around the anus
  • Feelings of pain or pressure in or around the anus
  • Recurrent presence of anal abscesses or pockets of pus

Causes and Risk Factors of Anal Cancer

Anal cancer risk is strongly associated with age, sex, and lifestyle. For instance, women over the age of 50 with a history of receptive anal intercourse and tobacco use are more likely to receive an anal cancer diagnosis. Immunosuppressed individuals or individuals with a weakened immune system due to human immunodeficiency virus (HIV) infection are also at risk of developing anal cancer.

Overall risk factors associated with anal cancer include:

  • Tobacco smoking or use
  • HPV and/or HIV infection
  • Weakened immune system due to untreated HIV infection or prolonged corticosteroid use
  • Age above 50 years
  • The presence of anal fistulas or abnormal openings in the anus
  • History of sexual intercourse with several partners
  • Poor social or living conditions
  • Frequent inflammation in or around the anus or rectum

Tests and Diagnosis of Anal Cancer

Anal cancer diagnosis involves a series of steps that include, but are not limited to, assessing your medical history, sexual history, smoking history, exposure to HPV, and age. Your doctor may also administer a physical examination, such as a digital rectal examination, to check for lumps or enlargements in your anus and rectum.

Your doctor may also perform visual exams that include anoscopy, proctoscopy, or endorectal ultrasound. If lumps or enlargements are present, then you doctor will perform other examinations to confirm the presence of anal cancer, such as a biopsy. During a biopsy, a small portion of the affected anal tissue is removed and examined under a microscope by a pathologist to confirm the presence of cancer.

Treatment and Care for Anal Cancer

Like most cancers, anal cancer treatment is more effective when it is administered at early stages. However, treatment options will vary depending on a patient’s medical status, such as if the patient is infected with HIV or has recurrent anal cancer symptoms. Other factors that determine the course of treatment for anal cancer are the size and location of the cancer tissue, the patient’s age (specifically if the patient is elderly), the stage of the cancer, and the cancerous tissue’s response to previous treatment.

Treatment options include:

  • Brachytherapy or internal radiation therapy
  • Radiotherapy, also known as radiation therapy
  • Chemoradiation therapy (CRT), or radiation therapy accompanied by chemotherapy
  • Surgical removal before and/or after CRT

Anal cancer cases in the elderly are often approached differently than cases in younger patients. This is because elderly patients may bear a higher risk of serious adverse effects from chemotherapy and radiation therapy depending on their health status. This cautious approach is also true for anal cancer patients with weakened or compromised immune systems. Individuals showing cancer remission, or the absence of cancer, several weeks after treatment are encouraged to undergo routine surveillance on a month-by-month basis for several years as directed by their doctors.