If you have signs or symptoms that could be from anal cancer, your doctor will start by asking about your medical history and family history and doing a physical exam. You may also need one or more of these procedures.
Digital Rectal Exam
Your physical exam may include a digital rectal exam. The doctor inserts a lubricated, gloved finger into your anus to feel for abnormal areas or masses. This exam can be a little uncomfortable but is very quick.
To examine your lower rectum and your anus, your doctor may do an anoscopy. The doctor inserts a thin, short, lighted tube called an anoscope through your anus into the lower part of your rectum. This way the doctor can look for any abnormalities.
During anoscopy, the doctor may remove small samples of tissue (or an entire tumor, if it’s small). A pathologist, a doctor who specializes in evaluating tissue samples, examines your samples under a microscope to see whether the cells are cancer or not. A biopsy provides a definitive diagnosis.
The only way to tell whether you have anal cancer is to examine samples of tissue. If cancer is found, your doctor may also want you to have imaging studies to get more information about whether your cancer has spread. These might include an X-ray, ultrasound, computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, and positron-emission tomography (PET) scan.