Symptoms & Signs

of Anal Cancer

Early-stage anal cancer may produce no signs or symptoms.  Symptoms of more advanced anal cancer may include the following.1,3

  • 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
  • Having these symptoms does not mean that an individual has anal cancer because these symptoms can be caused by other health conditions. If you have any of these symptoms however they should be brought to the attention of a health professional.


Anal cancer begins when healthy cells acquire a genetic change (mutation) that causes them to turn into abnormal cells. Although it isn’t clear what causes anal cancer the human papilloma virus (HPV) may play a role.2

Risk factors

A risk factor is anything that increases a person’s chance of developing cancer.  Risk factors can influence the development of cancer but most do not directly cause cancer. Many individuals with risk factors will never develop cancer and others with no known risk factors will.

Although most anal cancers develop sporadically, which means for no known reason the following factors may raise a person’s risk for developing anal cancer:

Risk factors for anal cancer include:

  • Human Papilloma Virus.
  • Multiple sexual partners. The greater the number of sexual partners the greater the greater your chance of acquiring HPV.
  • Early sexual activity. Having sex at an early age increases the risk of HPV.
  • A weak immune system. Individuals are more likely to develop anal cancer if their immune system is weakened by another health condition and infection with HPV.1,2

Next: Diagnosis & Tests for Anal Cancer


1 American Cancer Society. Cancer Facts & Figures 2016.

2 National Cancer Institute Fact Sheet. Human Papillomaviruses and Cancer: Questions and Answers.