Anal cancer
Cancer of the
anus is rare. Around 1,000 people are diagnosed with anal cancer each year in
the UK. The most common type of anal cancer is squamous cell carcinoma. Other
rarer types are basal cell carcinoma, adenocarcinoma and melanoma
The anus is the name for the
muscular opening at the very end of the large bowel.
It is controlled by a ring of
muscle called a sphincter that opens and closes to control bowel movements. The
area that connects the anus to the rectum is called the anal canal and is
around 3–4cm (1–1½in) long.
Anal cancer is slightly more
common in women than in men. Many factors can increase your risk of developing
anal cancer. These include:
Human papilloma virus (HPV)
Anal cancer is more likely to
develop in people who’ve had a viral infection called thehuman papilloma virus (HPV).
The risk of having HPV increases with the number of sexual partners you have.
Sexual activity
People who have anal
intercourse are more likely to develop anal cancer. This may be because they
are more likely to have anal HPV. However, anal cancer can also develop in
people who haven’t had anal intercourse or HPV.
Lowered immunity
The immune system is part of
the body's defence against infections and illnesses like cancer. Anal cancer is
more common in people who have a lowered immunity, such as people taking
medicines to suppress their immune system after an organ transplant or people
with conditions such as HIV.
Smoking
Smoking tobacco increases the
risk of developing anal cancer. We have more information about stopping smoking.
Although these factors can
increase a person’s risk of anal cancer, many people will not have these risk
factors and the cause of their cancer remains unknown.
The most common symptoms of
anal cancer include:
·
bleeding from the anus
·
pain, discomfort and itching around the anus
·
small lumps around the anus which may be confused
with piles (haemorrhoids)
·
difficulty controlling your bowels (faecal
incontinence)
·
discharge of a jelly-like substance from the anus
(mucus)
·
ulcers around the anus that can spread to the skin
of the buttocks.
Usually you begin by seeing
your GP who will examine you and refer you to either a surgeon or a specialist
in bowel conditions (a gastroenterologist).
At the hospital, the doctor
will examine you and ask about your general health and any previous medical
problems. They will do some tests before they can make a firm diagnosis of anal
cancer.
Rectal examination
This is also sometimes known
as a PR examination. A doctor examines your back passage with a gloved finger.
Women may also have an internal examination of their vagina, as the vaginal
wall is very close to the anal canal.
Biopsy
The doctor will put a thin tube
into your back passage to examine the anal canal and rectum. This is called a
proctoscopy. A small sample of tissue is taken from the tumour to be examined
under a microscope (biopsy). This can be done under local or general
anaesthetic. Sometimes a biopsy can be taken without needing to use a
proctoscope.
If the tests show that you
have anal cancer, you will need further tests to find out more about the
position of the cancer and to see if it has begun to spread.
CT (computerised tomography) scan
A CT scan takes a series of
x-rays that build up a three-dimensional picture of the inside of the body. The
scan is painless and takes 10-30 minutes. CT scans use small amounts of
radiation that are very unlikely to hurt you or anyone you come into contact with.
You will be asked not to eat or drink for at least four hours before the scan.
You may be given a drink or
injection of a dye that allows particular areas to be seen more clearly. For a
few minutes, this may make you feel hot all over. If you are allergic to iodine
or have asthma you could have a more serious reaction to the injection, so it’s
important to let your doctor know beforehand.
MRI (magnetic resonance imaging) scan
This test is similar to a CT
scan but uses magnetism, instead of x-rays, to build up a detailed picture of
areas of your body. Before the scan you may be asked to complete and sign a
checklist. This is to make sure it’s safe for you to have an MRI scan.
Before having the scan, you’ll
be asked to remove any metal belongings, including jewellery. Some people are
given an injection of dye into a vein in the arm. This is called a contrast
medium and can help the images from the scan show up more clearly. During the
test you will be asked to lie very still on a couch inside a long cylinder
(tube) for about 30 minutes. It’s painless but can be slightly uncomfortable,
and some people feel a bit claustrophobic during the scan. It’s also noisy, but
you’ll be given earplugs or headphones. You'll be able to hear, and speak to,
the person operating the scanner.
PET-CT scan
This is a combination of a PET
scan, which uses low-dose radiation to measure the activity of cells in
different parts of the body, and a CT scan. PET-CT scans give more detailed
information about the part of the body being scanned. They are not always necessary
but you can discuss with your doctor whether one would be useful in your case.
They are a new type of scan and you may have to travel to a specialist centre
to have one.
Endoanal ultrasound scan
This uses sound waves to form
a picture. A small probe that produces sound waves is passed into the back
passage (rectum). This scan can show the size and extent of the tumour.The test
is painless and takes about 30 minutes.
Staging
The stage of a cancer is a
term used to describe its size and whether it has spread beyond its original
site. Knowing the particular type and stage of the cancer helps the doctors to
decide on the most appropriate treatment.
Cancer can spread in the body,
either in the bloodstream or through the lymphatic system.
The lymphatic system is part of the body’s defence against infection and
disease. It is made up of a network of lymph nodes connected by fine ducts
containing lymph fluid. Your doctors will usually check the nearby lymph nodes
when staging your cancer.
Stage 1
The cancer only affects the
anus and is smaller than 2cm (¾in) in size. It has not begun to spread into the
sphincter muscle.
Stage 2
The cancer is bigger than 2cm
(¾in) in size, but hasn't spread into nearby lymph nodes or to other parts of
the body.
Stage 3A
The cancer has spread to the
lymph nodes near the rectum, or to nearby organs such as the bladder or vagina.
Stage 3B
The cancer has spread to lymph
nodes in the groin and pelvis, or to lymph nodes close to the anus, as well as
nearby organs such as the bladder or vagina.
Stage 4
The cancer has spread to lymph
nodes in the abdomen or to other parts of the body, such as the liver.
A different staging system
called the TNM staging system is sometimes used instead of the number system
described above.
·
T describes the size of the tumour and whether it
has spread into nearby organs.
·
N describes whether the cancer has spread to the
lymph nodes.
·
M describes whether the cancer has spread to
another part of the body, such as the liver (secondary or metastatic cancer).
This system is more complex
and can give more precise information about the tumour stage.
If the cancer comes back after
initial treatment, it is known as recurrent cancer.
Grading
Grading refers to the
appearance of cancer cells under a microscope and gives an idea of how quickly
a cancer may develop. Low-grade means that the cancer cells look very much like
normal cells. They’re usually slow-growing and are less likely to spread. In
high-grade tumours the cells look very abnormal, are likely to grow more
quickly and are more likely to spread.
The National Institute for Health and
Clinical Excellence (NICE) recommends that people with an anal
cancer are treated by a specialist team. These teams aren't available in all
hospitals, so you may have to travel to another hospital for your treatment.
The main type of treatment for
anal cancer is a combination of radiotherapy andchemotherapy. The two
treatments are normally given at the same time (chemoradiation) but may also be
given in sequence, one following the other. Combined treatment is usually very
successful. If radiotherapy and chemotherapy are given at the same time, the
side effects can be more severe.
Surgery may be used
to treat small anal tumours or be used in combination with chemotherapy or
radiotherapy for advanced anal cancer.
Consent
Before you have any treatment,
your doctor will give you full information about what it involves and explain
its aims to you. They will usually ask you to sign a form saying that you give permission
(consent) for the hospital staff to give you the treatment. No
medical treatment can be given without your consent.
Benefits and disadvantages of treatment
Treatment can be given for
different reasons and the potential benefits will vary for each person. If you
have been offered treatment that aims to cure your cancer, deciding whether to
have the treatment may not be difficult. However, if a cure is not possible and
the treatment is to control the cancer for a period of time, it may be more
difficult to decide whether or not to go ahead.
If you feel that you can't
make a decision about treatment immediately, you can ask for more time to
decide.
You are free to choose not to
have the treatment. You don't have to give a reason but it can be helpful to
let the staff know your concerns so that they can give you the best advice.
This is the use of high-energy
x-rays to destroy cancer cells while doing as little harm as possible to normal
cells. Beams are directed at the cancer from outside the body (external
radiotherapy) as a series of short, daily treatments using equipment similar to
a large x-ray machine. The treatment is often given for a few minutes each
weekday for 4-6 weeks.
Possible side effects during radiotherapy treatment
Diarrhoea and
passing wind
During the course of treatment
you may have changes in how your bowel works, such as diarrhoea or
passing more wind.
These can sometimes be reduced by avoiding particular foods. Your doctor or a
dietitian at the hospital can give you advice about this.
Effects on the
skin
It’s very likely that your
skin will be sore in the area being treated - around the anus, and perhaps
in the scrotal area for men and in the vulval area for women. This soreness
usually starts about 2-3 weeks after treatment begins. The skin may become
blistered and sore and the area may be quite painful. You can be prescribed
painkillers to help with this.
The hospital staff will keep
an eye on the area and will advise you how to look after your skin. It’s
important that you only use products they recommend. If it becomes very painful
to pass urine, the staff may suggest that you have a fine tube (catheter) put
into your bladder to drain the urine. This is then removed once your skin has
healed.
Hair loss
It’s common to lose your pubic
hair. Hair should grow back after treatment finishes, although the hair loss
may be permanent.
Extreme
tiredness (fatigue)
Fatigue is
a common side effect of radiotherapy for anal cancer.
Vaginal dryness
Women may develop dryness and
narrowing of the vagina. Because of this you may need to use a lubricating
jelly during sex. You may also be advised to use a vaginal dilator with a
lubricating jelly to keep the vaginal walls open and supple. Your doctor or
specialist nurse can give you more information about this.
These side effects usually
decrease gradually once the treatment has ended but it may take some months for
skin changes to go back to normal. A few people find that the way their bowel
works is permanently altered, however for most people the change is not usually
severe. It can usually be easily managed although you may need to take
medication.
It's important to discuss any
problems with your doctor or specialist nurse, as there are often ways to
reduce them.
Possible side effects after radiotherapy treatment
Infertility (loss of the
ability to have children) If you are concerned about the risk of becoming
infertile, it's important to discuss this with your specialist before starting
treatment.
Menopause
Women who have not been
through the menopause may find that treatment brings on an early menopause
which can cause hot flushes and sweats. Your doctor or nurse can give you
advice on managing menopausal symptoms.
Impotence
Men may become unable to have
an erection (impotence) after treatment. It’s important to let your doctor know
if this happens to you as there are different ways of managing impotence. We
discuss some of these in our information about sexuality and cancer.
This is the use of anti-cancer
(cytotoxic) drugs to destroy cancer cells. The chemotherapy drugs are usually
given by injection into a vein (intravenously). Drugs commonly used to treat anal
cancer include mitomycin and fluorouracil (5FU).
Sometimes a drug called capecitabine,
which is taken as a tablet, is used instead of fluorouracil.
Chemotherapy can temporarily
reduce the number of normal cells in your blood. When your white blood cell
count is low you are more likely to get an infection. You‘ll be given
information about this and advised about who to call if you have any problems. During
chemotherapy your blood will be tested regularly and, if necessary, you’ll be
given antibiotics to treat any infection.
Possible side effects of chemotherapy
Anaemia
If your red blood cell count
is low (anaemia), you may tire very quickly. You may have blood transfusions if
you become anaemic. If the number of platelets is low you may bruise more
easily.
Nausea and
vomiting
You may feel sick (nauseous) or be sick (vomiting).
Hair loss
Some chemotherapy drugs can
cause temporary hair loss.
Your doctor or nurse will be able to tell you if the drugs you’re having are
likely to cause hair loss. They can also give you information about coping with
this.
Sore mouth
Chemotherapy drugs may make
your mouth sore and
cause small mouth ulcers. Regular mouthwashes are important and your nurse will
show you how to use these properly.
Diet
If you don’t feel like eating
meals, you can supplement your diet with nutritious drinks or soups. A wide
variety of drinks are available and you can buy them at most chemists. You can
ask your doctor to refer you to a dietitian for advice about your diet.
Surgery may be used for small
tumours. It can also be used if your treatment doesn't completely get rid of
the cancer, or if there are signs that the cancer has returned. Sometimes it’s
used if radiotherapy isn’t appropriate, for example if you’ve had radiotherapy
to the area before. Occasionally it’s used to relieve symptoms before treatment
with chemoradiation.
Local resection
This may be used for small
tumours on the outside of the anus. The operation only removes the area of the
anus containing the cancer cells.
The anal sphincter isn't
usually affected, so how the bowel works remains the same for most people. Your
doctors may sometimes recommend that you have radiotherapy or chemoradiation
after you’ve had surgery.
Abdominoperineal resection
This is the removal of the
anus and rectum. The operation requires a permanent colostomy, which involves
diverting the open end of the bowel to the surface of the abdomen (tummy area),
to allow faeces to be passed out of the body into a colostomy bag. The opening
on the abdominal wall is known as a stoma.
Although the idea of a
colostomy is often frightening and distressing at first, most people find that
they adapt over time and can return to their normal activities.
You can get support and advice
from the stoma nurse in your hospital. We also have information about having a
colostomy.
Surgery to relieve symptoms
Occasionally surgery to form a
temporary colostomy may be needed before chemoradiation starts. If the cancer
is causing incontinence, a blockage in the bowel or significant pain, a
temporary colostomy can sometimes help relieve these symptoms.
It's not unusual to have side
effects for a time following treatment for anal cancer. These may include
feeling bloated, having wind, diarrhoea and occasional incontinence. These side
effects can be distressing but are usually temporary and improve over several
months. Your doctor, nurse or dietitian will be able to give you advice about
how to manage any side effects.
You will be followed up for
between 5-10 years. If you have side effects which persist, you may be referred
to another specialist for advice and treatment.
Having investigations and
treatment for cancer can be a very stressful experience. You may have many emotions including
anxiety, anger and fear. These are all normal reactions and are part of the
process many people go through as they try to come to terms with their
condition.
Many people find it helpful to
talk things over with their doctor or nurse, or with one of ourcancer support specialists.
Close friends and family can also offer support.
No comments:
Post a Comment