The anus is the end of the large intestine, below the rectum. Stool passes through the anus to
leave the body. The anus is made up partly of skin layers and partly from intestinal tissues. Two
muscles, called sphincter muscles, control the passage of stool from the body. The anal canal,
the part of the anus between the rectum and the anal opening, is about 1 ½ inches long.
Anal cancer makes up about 1-2 percent of
all cancers of the large bowel and its outlet.
Most are called squamous cell cancers.
These arise from the outer layer of the skin.
Anal cancer can spread into nearby tissues,
such as the skin and sphincter muscle, or
organs such as the prostate, bladder, or
vagina. Tumor cells can spread via the
lymph system to nearby or distant lymph
nodes. They can also travel through the
blood stream to distant organs. Anal cancer
is highly treatable. It can most often be
cured in the early stages.
Chronic anal inflammation is linked with
anal cancer. Listed below are some of the
ξ Age – increased risk over age 50
ξ Having multiple sexual partners
ξ Human Papillomavirus (HPV)
ξ Fissures, fistulas, hemorrhoids, and
certain sexually transmitted diseases
ξ Receptive anal sex
ξ Smoking cigarettes
Some of the symptoms of anal cancer are
listed below. In the early stages there may
be no symptoms.
ξ Bleeding or discharge from the anus
ξ Pain or pressure in the rectal and
ξ Anal itching
ξ A lump near the anus
ξ A change in bowel habits
The prognosis depends on certain factors.
Some of theses are listed below.
ξ The size of the tumor. There are
higher cure rates with smaller
ξ Where the tumor is in the anus
ξ Whether the cancer has spread to the
lymph nodes or distant organs
These tests may be used to diagnose anal
cancer. They also help to decide on the
stage of disease (extent of the cancer). This
is helpful to know in order to make a
History and physical exam - a
digital rectal exam, review of health
habits, past illness, and treatments
Anoscopy – an exam of the anus and
lower rectum using a scope.
Proctoscopy – an exam of the
rectum using a scope.
Transrectal or transanal ultra
sound – A scope is placed into the
rectum and the ultrasound is done.
This test helps to find out if the
cancer has spread to local lymph
Stages of Anal Cancer
The stage of anal cancer describes whether
the cancer has remained within the anus, has
spread to nearby or distant lymph nodes, or
Stage 0 – cancer is found only in the inner
lining of the anus.
Stage I – the tumor is 2 cm or smaller
Stage II – the tumor is larger than 2 cm
Stage IIIA – the tumor has spread
ξ to lymph nodes near the rectum, or
ξ nearby organs
Stage IIIB – the tumor has spread
ξ to nearby organs and to lymph
nodes near the rectum, or
ξ to lymph nodes on one side of the
pelvis and/or groin, and may have
spread to nearby organs, or
ξ to lymph nodes near the rectum and
in the groin, and/or lymph nodes on
both sides of the pelvis and/or
groin, and may have spread to
Stage IV – the tumor may be any size and
cancer may have spread to lymph nodes or
nearby organs and has spread to distant parts
of the body
Recurrent anal cancer – cancer that has
recurred (come back) after it has been
treated. It may come back in the anus or in
other parts of the body.
Radiation Therapy is a cancer treatment
that uses radiation to kill cancer cells.
There are two types of radiation.
External beam – uses a machine
outside the body to send radiation to
Internal beam – uses a radioactive
substance sealed in needles, seeds,
wires, or catheters that are placed
into or near the cancer.
Chemotherapy (chemo) uses drugs to stop
the growth of cancer cells. Chemo is a
treatment that can reach the cancer cells
throughout the body. It is used with
Surgery is used if there is still disease after
the chemoradiotherapy. Surgery may be
done for small amounts of tumor, keeping
sphincter muscle control. For more
advanced disease, surgery may be required
to remove the anus, rectum, and lymph
nodes. A colostomy may be needed.
Careful follow-up exams are needed.
Exams with anoscopy should be performed
every 3 months for 3 years, then every 6
months for 2-3 years. Careful exams of
lymph nodes, liver function blood tests, and
CT scans are all part of complete follow-up
This information has been reproduced with permission of the National Cancer Institute. For more information
please visit their website @www.nci.nih.gov.
Your health care team may have given you this information as part of your care. If so, please use it and call if you
have any questions. If this information was not given to you as part of your care, please check with your doctor. This
is not medical advice. This is not to be used for diagnosis or treatment of any medical condition. Because each
person’s health needs are different, you should talk with your doctor or others on your health care team when using
this information. If you have an emergency, please call 911. Copyright © 7/2016 University of Wisconsin Hospitals
and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#6618