Colorectal Cancer Association of Canada - CCAC

Anal Cancer > Diagnosis of Anal Cancer  

Tests that examine the rectum and anus are used to detect and diagnose anal cancer. The following procedures may be used:

  • Medical history and physical examination: a healthcare professional will take a history of the patient’s health habits, present symptoms, and past illnesses and treatments. In addition, an exam of the body will be performed. The doctor will check general signs of health, including signs of disease, such as lumps or anything else that seems unusual.
  • Digital rectal examination (DRE): an exam of the anus and rectum. The doctor or nurse inserts a lubricated, gloved finger into the lower part of the rectum to feel for lumps or anything else that seems unusual.

Digital rectal exam (DRE). Image courtesy of the National Cancer Institute (

  • Anoscopy: an exam of the anus and lower rectum using a short, illuminated tube (an anoscope).
  • Proctoscopy: an exam of the rectum using a short, illuminated tube with a camera (a proctoscope).
  • Endo-anal or endorectal ultrasound: a procedure in which an ultrasound probe (transducer) is inserted into the anus or rectum. High-energy sound waves bounce off internal tissues or organs and make echoes. These echoes form images of bodily structures called a sonogram.
  • Biopsy: tissues or cells are removed from the body so they can be viewed under a microscope by a pathologist to check for signs of cancer. If an abnormality is observed during an anoscopy, a biopsy may be performed at this time.
  • Anal Pap: Similar to a Pap test, anal cytology, or an anal pap, looks for abnormal cells in the anal lining. This test may help find anal cancer at the earliest, most treatable stages.

Source: National Cancer Institute (