The GALE
ENCYCLOPEDIA
of
C
ancer
The GALE
ENCYCLOPEDIA
of
C
ancer
ELLEN THACKERY, EDITOR
A GUIDE TO CANCER AND ITS TREATMENTS
V OLUME
L-Z
GENERAL INDEX
2
Lactulose see Laxatives
Lambert-Eaton syndrome see Eaton-
Lambert syndrome
Langerhans cell histiocytosis see
Histiocytosis X
Laparoscopy
Definition
Laparoscopy is a type of surgical procedure in which
a small incision is made, usually in the navel, through
which a viewing tube (laparoscope) is inserted. The view-
ing tube has a small camera on the eyepiece. This allows
the doctor to examine the abdominal and pelvic organs on
a video monitor connected to the tube. Other small inci-
sions can be made to insert instruments to perform proce-
dures. Laparoscopy can be done to diagnose conditions or

Laparoscopy is used to determine the cause of pelvic
pain or gynecological symptoms that cannot be con-
firmed by a physical exam or ultrasound. For example,
ovarian cysts, endometriosis, ectopic pregnancy, or
blocked fallopian tubes can be diagnosed using this pro-
cedure. It is an important tool when trying to determine
the cause of infertility.
Operative procedure
While laparoscopic surgery to completely remove
cancerous tumors, surrounding tissues, and lymph nodes
is used on a limited basis, this type of operation is widely
used in noncancerous conditions that once required open
surgery. These conditions include:
•Tubal ligation. In this procedure, the fallopian tubes are
sealed or cut to prevent subsequent pregnancies.
• Ectopic pregnancy. If a fertilized egg becomes embed-
ded outside the uterus, usually in the fallopian tube, an
operation must be performed to remove the developing
embryo. This often can be done with laparoscopy.
• Endometriosis. This is a condition in which tissue from
inside the uterus is found outside the uterus in other
parts of (or on organs within) the pelvic cavity. This can
L
GALE ENCYCLOPEDIA OF CANCER
565
cause cysts to form. Endometriosis is diagnosed with
laparoscopy, and in some cases the cysts and other tis-
sue can be removed during laparoscopy.
• Hysterectomy. This procedure to remove the uterus can,
in some cases, be performed using laparoscopy. The

cancerous lesions that are 0.4 in (10 mm) in size,
laparoscopy is capable of locating lesions that are as
small as 0.04 in (1 millimeter).
•Pancreatic cancer. Laparoscopy has been used to evalu-
ate pancreatic cancer for years. In fact, the first reported
use of laparoscopy in the United States was in a case
involving pancreatic cancer.
• Esophageal and stomach cancers. Laparoscopy has been
found to be more effective than magnetic resonance
imaging (MRI) or computed tomography (CT) in diag-
nosing the spread of cancer from these organs.
• Hodgkin’s disease. Some patients with Hodgkin’s dis-
ease have surgical procedures to evaluate lymph nodes
for cancer. Laparoscopy is sometimes selected over
laparotomy for this procedure. In addition, the spleen
may be removed in patients with Hodgkin’s disease.
Laparoscopy is the standard surgical technique for this
procedure, which is called a splenectomy.
• Prostate cancer. Patients with prostate cancer may
have the nearby lymph nodes examined. Laparoscopy
is an important tool in this procedure.
Cancer treatment
Laparoscopy is sometimes used as part of a pallia-
tive cancer treatment. This type of treatment is not a
cure, but can often lessen the symptoms. An example is
the feeding tube, which cancer patients may have if they
are unable to take in food by mouth. The feeding tube
provides nutrition directly into the stomach. Inserting
the tube with a laparoscopy saves the patient the ordeal
of open surgery.

from the camera attached to the end of the laparoscope is
seen on a video monitor.
Sometimes, additional small incisions are made to
insert other instruments that are used to lift the tubes and
ovaries for examination or to perform surgical procedures.
Preparation
Patients should not eat or drink after midnight on the
night before the procedure.
Aftercare
After the operation, nurses will check the vital signs
of patients who had general anesthesia. If there are no
complications, the patient may leave the hospital within
four to eight hours. (Traditional abdominal surgery
requires a hospital stay of several days).
There may be some slight pain or throbbing at the inci-
sion sites in the first day or so after the procedure. The gas
that is used to expand the abdomen may cause discomfort
under the ribs or in the shoulder for a few days. Depending
on the reason for the laparoscopy in gynecological proce-
dures, some women may experience some vaginal bleed-
ing. Many patients can return to work within a week of
surgery and most are back to work within two weeks.
Risks
Laparoscopy is a relatively safe procedure, especial-
ly if the physician is experienced in the technique. The
risk of complication is approximately 1%.
The procedure carries a slight risk of puncturing a
blood vessel or organ, which could cause blood to seep
into the abdominal cavity. Puncturing the intestines could
allow intestinal contents to seep into the cavity. These are

nodes that were examined.
Abnormal results
A diagnostic laparoscopy may reveal cancerous or
benign masses or lesions. Abnormal findings include
tumors or cysts, infections (such as pelvic inflammatory
disease), cirrhosis, endometriosis, fibroid tumors, or an
accumulation of fluid in the cavity. If a doctor is check-
ing for the spread of cancer, the presence of malignant
lesions in areas other than the original site of malignancy
is an abnormal finding.
See Also Endoscopic retrograde cholangiopancre-
atography; Gynecologic cancers; Liver biopsy; Lymph
GALE ENCYCLOPEDIA OF CANCER
567
Laparoscopy
node biopsy; Nutritional support; Tumor grading; Tumor
staging; Ultrasonography
Resources
BOOKS
Carlson, Karen J., Stephanie A. Eisenstat, and Terra Ziporyn.
The Harvard Guide to Women’s Health. Cambridge, MA:
Harvard University Press, 1996.
Cunningham, F. Gary, Paul C. MacDonald, et al. Williams Obstet-
rics, 20th ed. Stamford, CT:Appleton & Lange, 1997.
Kurtz, Robert C., and Robert J. Ginsberg. “Cancer Diagnosis:
Endoscopy.” In Cancer: Principles & Practice of Oncolo-
gy. , edited by Vincent T. DeVita Jr. Philadelphia: Lippin-
cott, Williams & Wilkins, 2001, 725-27.
Lefor, Alan T. “Specialized Techniques in Cancer Manage-
ment.” In Cancer: Principles & Practice of Oncology, 6th

ed is sometimes called the Adam’s apple.
The larynx has two main functions. It contains the
vocal cords, cartilage, and small muscles that make up
the voice box. When a person speaks, small muscles
tighten the vocal cords, narrowing the distance between
them. As air is exhaled past the tightened vocal cords, it
creates sounds that are formed into speech by the mouth,
lips, and tongue.
The second function of the larynx is to allow air to
enter the trachea and to keep food, saliva, and foreign
material from entering the lungs. A flap of tissue called
the epiglottis covers the trachea each time a person swal-
lows. This blocks foreign material from entering the
lungs. When not swallowing, the epiglottis retracts, and
air flows into the trachea. During treatment for cancer of
the larynx, both of these functions may be lost.
Cancers of the larynx develop slowly. About 95% of
these cancers develop from thin, flat cells similar to skin
cells called squamous epithelial cells. These cells line the
larynx. Gradually, the squamous epithelial cells begin to
change and are replaced with abnormal cells. These
abnormal cells are not cancerous but are pre-malignant
cells that have the potential to develop into cancer. This
condition is called dysplasia. Most people with dysplasia
never develop cancer. The condition simply goes away
without any treatment, especially if the person with dys-
plasia stops smoking or drinking alcohol.
The larynx is made up of three parts, the glottis, the
supraglottis, and the subglottis. Cancer can start in any of
these regions. Treatment and survival rates depend on

The subglottis is the region below the vocal cords.
Cancer starting in the subglottis region is rare. When it
does, it is usually detected only after it has spread to the
vocal cords, where it causes obvious symptoms such as
hoarseness. Because the cancer has already begun to
spread by the time it is detected, survival rates are gener-
ally lower than for cancers in other parts of the larynx.
Demographics
About 12,000 new cases of cancer of the larynx
develop in the United States each year. Each year, about
3,900 die of the disease. Laryngeal cancer is between four
and five times more common in men than in women.
Almost all men who develop laryngeal cancer are over age
55. Laryngeal cancer is about 50% more common among
African-American men than among other Americans.
It is thought that older men are more likely to devel-
op laryngeal cancer than women because the two main
risk factors for acquiring the disease are lifetime habits
of smoking and alcohol abuse. More men smoke and
drink more than women, and more African-American
men are heavy smokers than other men in the United
States. However, as smoking becomes more prevalent
among women, it seems likely that more cases of laryn-
geal cancer in females will be seen.
Causes and symptoms
Laryngeal cancer develops when the normal cells
lining the larynx are replaced with abnormal cells (dys-
plasia) that become malignant and reproduce to form
tumors. The development of dysplasia is strongly linked
to life-long habits of smoking and heavy use of alcohol.

On the first visit to a doctor for symptoms that suggest
laryngeal cancer, the doctor first takes a complete medical
history, including family history of cancer and lifestyle
information about smoking and alcohol use. The doctor
also does a physical examination, paying special attention
to the neck region for lumps, tenderness, or swelling.
The next step is examination by an otolaryngologist,
or ear, nose, and throat (ENT) specialist. This doctor also
performs a physical examination, but in addition will
GALE ENCYCLOPEDIA OF CANCER
569
Laryngeal cancer
A pathology photograph of an extracted tumor found on the
larynx. (Photograph by William Gage. Custom Medical Stock
Photo. Reproduced by permission.)
also want to look inside the throat at the larynx. Initially,
the doctor may spray a local anesthetic on the back of the
throat to prevent gagging, then use a long-handled mirror
to look at the larynx and vocal cords. This examination is
done in the doctor’s office. It may cause gagging but is
usually painless.
A more extensive examination involves a laryn-
goscopy. In a laryngoscopy, a lighted fiberoptic tube
called a laryngoscope that contains a tiny camera is
inserted through the patient’s nose and mouth and snaked
down the throat so that the doctor can see the larynx and
surrounding area. This procedure can be done with a
sedative and local anesthetic in a doctor’s office. More
often, the procedure is done in an outpatient surgery clinic
or hospital under general anesthesia. This allows the doc-

nets and radio waves to create more detailed cross-sec-
tional scans than computed tomography. This detailed
information is needed if surgery on the larynx area is
planned.
• Barium swallow. Barium is a substance that, unlike soft
tissue, shows up on x rays. Swallowed barium coats the
throat and allows x-ray pictures to be made of the tis-
sues lining the throat.
• Chest x ray. Done to determine if cancer has spread to
the lungs. Since most people with laryngeal cancer are
smokers, the risk of also having lung cancer or emphy-
sema is high.
•Fine needle aspiration (FNA) biopsy. If any lumps on
the neck are found, a thin needle is inserted into the
lump, and some cells are removed for analysis by the
pathologist.
• Additional blood and urine tests. These tests do not
diagnose cancer, but help to determine the patient’s
general health and provide information to determine
which cancer treatments are most appropriate.
Treatment team
An otolaryngologist and an oncologist (cancer spe-
cialist) generally lead the treatment team. They are sup-
ported by radiologists to interpret CT and MRI scans, a
head and neck surgeon, and nurses with special training
in assisting cancer patients.
A speech pathologist is often involved in treatment,
both before surgery to discuss various options for com-
munication if the larynx is removed, and after surgery to
teach alternate forms of voice communication. A social

STAGE II. The cancer is only in the larynx and has
not spread to lymph nodes in the area or to other parts of
the body. The exact definition of stage II depends on
where the cancer started, as follows:
• Supraglottis: The cancer is in more than one area of the
supraglottis, but the vocal cords can move normally.
•Glottis: The cancer has spread to the supraglottis or the
subglottis or both. The vocal cords may or may not be
able to move normally.
• Subglottis: The cancer has spread to the vocal cords,
which may or may not be able to move normally.
STAGE III. Either of the following may be true:
•The cancer has not spread outside of the larynx, but the
vocal cords cannot move normally, or the cancer has
spread to tissues next to the larynx.
•The cancer has spread to one lymph node on the same
side of the neck as the cancer, and the lymph node mea-
sures no more than 3 centimeters (just over 1 inch).
STAGE IV. Any of the following may be true:
•The cancer has spread to tissues around the larynx,
such as the pharynx or the tissues in the neck. The
lymph nodes in the area may or may not contain cancer.
•The cancer has spread to more than one lymph node on
the same side of the neck as the cancer, to lymph nodes
on one or both sides of the neck, or to any lymph node
that measures more than 6 centimeters (over 2 inches).
•The cancer has spread to other parts of the body.
RECURRENT. Recurrent disease means that the cancer
has come back (recurred) after it has been treated. It may
come back in the larynx or in another part of the body.

• Can you suggest any support groups that would
be helpful to me or my family?
Stage III and stage IV cancers are usually treated
with total laryngectomy. This is an operation to remove
the entire larynx. Sometimes other tissues around the lar-
ynx are also removed. Total laryngectomy removes the
vocal cords. Alternate methods of voice communication
must be learned with the help of a speech pathologist.
Smaller tumors are sometimes treated by partial
laryngectomy. The goal is to remove the cancer but save
as much of the larynx (and corresponding speech capa-
bility) as possible. Very small tumors or cancer in situ are
sometimes successfully treated with laser excision
surgery. In this type of surgery, a narrowly targeted beam
of light from a laser is used to remove the cancer.
Advanced cancer (Stages III and IV) that has spread
to the lymph nodes often requires an operation called a
neck dissection. The goal of a neck dissection is to
remove the lymph nodes and prevent the cancer from
spreading. There are several forms of neck dissection. A
radical neck dissection is the operation that removes the
most tissue.
Several other operations are sometimes performed
because of laryngeal cancer. A tracheotomy is a surgical
procedure in which an artificial opening is made in the
trachea (windpipe) to allow air into the lungs. This oper-
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Laryngeal cancer
ation is necessary if the larynx is totally removed. A gas-

ing fractions into smaller doses given more than once a
day (hyperfractionation). Side effects of radiation thera-
py include dry mouth, sore throat, hoarseness, skin prob-
lems, trouble swallowing, and diminished ability to taste.
CHEMOTHERAPY. Chemotherapy is the use of drugs
to kill cancer cells. Unlike radiation therapy, which is tar-
geted to a specific tissue, chemotherapy drugs are either
taken by mouth or intravenously (through a vein) and cir-
culate throughout the whole body. They are used mainly
to treat advanced laryngeal cancer that is inoperable or
that has metastasized to a distant site. Chemotherapy is
often used after surgery or in combination with radiation
therapy. Clinical trials are underway to determine the
best combination of treatments for advanced cancer.
The two most common chemotherapy drugs used to
treat laryngeal cancer are cisplatin and fluorouracil (5-
FU). There are many side effects associated with
chemotherapy drugs, including nausea and vomiting,
loss of appetite (anorexia), hair loss (alopecia), diar-
rhea, and mouth sores. Chemotherapy can also damage
the blood-producing cells of the bone marrow, which can
KEY TERMS
Dysplasia—The abnormal change in size, shape
or organization of adult cells.
Lymph—Clear, slightly yellow fluid carried by a
network of thin tubes to every part of the body.
Cells that fight infection are carried in the lymph.
Lymphatic system—Primary defense against infec-
tion in the body. The lymphatic system consists of
tissues, organs, and channels (similar to veins) that

Alternative and complementary therapies
Alternative and complementary therapies range
from herbal remedies, vitamin supplements, and special
diets to spiritual practices, acupuncture, massage, and
similar treatments. When these therapies are used in
GALE ENCYCLOPEDIA OF CANCER
572
Laryngeal cancer
addition to conventional medicine, they are called com-
plementary therapies. When they are used instead of con-
ventional medicine, they are called alternative therapies.
Complementary or alternative therapies are widely
used by people with cancer. One large study published in
the Journal of Clinical Oncology in July, 2000 found that
83% of all cancer patients studied used some form of com-
plementary or alternative medicine as part of their cancer
treatment. No specific alternative therapies have been
directed toward laryngeal cancer. However, good nutrition
and activities that reduce stress and promote a positive view
of life have no unwanted side effects and appear to be bene-
ficial in boosting the immune system in fighting cancer.
Unlike traditional pharmaceuticals, complementary
and alternative therapies are not evaluated by the United
States Food and Drug Administration (FDA) for either
safety or effectiveness. These therapies may have inter-
actions with traditional pharmaceuticals. Patients should
be wary of “miracle cures” and notify their doctors if
they are using herbal remedies, vitamin supplements or
other unprescribed treatments. Alternative and experi-
mental treatments normally are not covered by insurance.

and surgical therapy, radiation and chemotherapy, and
different combinations of chemotherapy drugs. Other
studies are examining the most effective timing and dura-
tion of radiation therapy.
Current information on what clinical trials are avail-
able and where they are being held is available by enter-
ing the search term “laryngeal cancer” at the following
web sites:
• National Cancer Institute. <.
gov> or (800) 4-CANCER.
• National Institutes of Health Clinical Trials. <http://
clinicaltrials.gov>
• Center Watch: A Clinical Trials Listing. <http://www.
centerwatch.com>
Prevention
By far, the most effective way to prevent laryngeal
cancer is not to smoke. Smokers who quit smoking also
significantly decrease their risk of developing the dis-
ease. Other ways to prevent laryngeal cancer include lim-
iting the use of alcohol, eating a well-balanced diet, seek-
ing treatment for prolonged heartburn, and avoiding
inhaling asbestos and chemical fumes.
Special concerns
Being diagnosed with cancer is a traumatic event.
Not only is one’s health affected, one’s whole life sud-
denly revolves around trips to the doctor for cancer treat-
ment and adjusting to the side effects of these treatments.
This is stressful for both the cancer patient and his or her
family members. It is not unusual for family members to
feel resentful of the changes that occur in the family, and

National Center for Complementary and Alternative Medicine.
P. O. Box 8218, Silver Spring, MD 20907-8281. (888)
644-6226. <>
OTHER
“What you Need to Know About Cancer of the Larynx.” Can-
cerNet November 2000. 19 July 2001 <http://www.
cancernet.nci.nih.gov>
“Laryngeal Cancer.” CancerNet 19 July 2001 <http://www.
graylab. ac.uk/cancernet/201519.html#3_STAGE
EXPLANATION>
Tish Davidson, A.M.
Laryngeal nerve palsy
Description
Laryngeal nerve palsy is damage to the recurrent
laryngeal nerve (or less commonly the vagus nerve) that
results in paralysis of the larynx (voice box). Paralysis
may be temporary or permanent. Damage to the recur-
rent laryngeal nerve is most likely to occur during
surgery on the thyroid gland to treat cancer of the thy-
roid. Laryngeal nerve palsy is also called recurrent laryn-
geal nerve damage.
The vagus nerve is one of 12 cranial nerves that con-
nect the brain to other organs in the body. It runs from the
brain to the large intestine. In the neck, the vagus nerve
gives off a paired branch nerve called the recurrent laryn-
geal nerve. The recurrent laryngeal nerves lie in grooves
along either side of the trachea (windpipe) between the
trachea and the thyroid gland.
The recurrent laryngeal nerve controls movement of
the larynx. The larynx is located where the throat divides

tumors in the neck and chest or diseases in the chest such
as aortic aneurysms. Both tumors and aneurysms press
on the nerve, and the pressure causes damage.
Treatments
Once the recurrent laryngeal nerve is damaged, there
is no specific treatment to heal it. With time, most cases
of recurrent laryngeal palsy improve on their own. In the
event of severe damage, the larynx may be so paralyzed
that air cannot flow past it into the lungs. When this hap-
pens, an emergency tracheotomy must be performed to
save the patient’s life. A tracheotomy is a surgical proce-
dure to make an artificial opening in the trachea (wind-
pipe) to allow air to bypass the larynx and enter the
lungs. If paralysis of the larynx is temporary, the tra-
cheotomy hole can be surgically closed when it is no
longer needed.
Some normal variation in the location of the recur-
rent laryngeal nerve occurs among individuals. Occa-
sionally the nerves are not located exactly where the sur-
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Laryngeal nerve palsy
geon expects to find them. Choosing a board certified
head and neck surgeon who has had a lot of experience
with thyroid operations is the best way to prevent laryn-
geal nerve palsy.
Alternative and complementary therapies
There are no alternative or complementary therapies
to heal laryngeal nerve palsy. The passage of time alone
restores speech to most people. Some alternatives for

done when cancer is limited to one spot. Only the area
with the tumor is removed. Laryngectomies may also be
performed when other cancer treatment options, such as
radiation therapy or chemotherapy,fail.
Precautions
Laryngectomy is done only after cancer of the lar-
ynx has been diagnosed by a series of tests that allow the
otolaryngologist (a specialist often called an ear, nose,
and throat doctor) to look into the throat and take tissue
samples (biopsies) to confirm and stage the cancer. Peo-
ple need to be in good general health to undergo a laryn-
gectomy, and will have standard pre-operative blood
work and tests to make sure they are able to safely with-
stand the operation.
Description
The larynx is located slightly below the point where
the throat divides into the esophagus, which takes food to
the stomach, and the trachea (windpipe), which takes air
to the lungs. Because of its location, the larynx plays a
critical role in normal breathing, swallowing, and speak-
ing. Within the larynx, vocal folds (often called vocal
cords) vibrate as air is exhaled past, thus creating speech.
The epiglottis protects the trachea, making sure that only
air gets into the lungs. When the larynx is removed, these
functions are lost.
Once the larynx is removed, air can no longer flow
into the lungs. During this operation, the surgeon removes
the larynx through an incision in the neck. The surgeon
also performs a tracheotomy. He makes an artificial open-
ing called a stoma in the front of the neck. The upper por-

remove any fluids that collect. These drains are removed
after several days.
It takes two to three weeks for the tissues of the
throat to heal. During this time, the laryngectomee can-
not swallow food and must receive nutrition through a
tube inserted through the nose and down the throat into
the stomach. During this time, even people with partial
laryngectomies are unable to speak.
When air is drawn in normally through the nose, it is
warmed and moistened before it reaches the lungs. When
air is drawn in through the stoma, it does not have the
opportunity to be warmed and humidified. In order to
keep the stoma from drying out and becoming crusty,
laryngectomees are encouraged to breathe artificially
humidified air. The stoma is usually covered with a light
cloth to keep it clean and to keep unwanted particles
from accidentally entering the lungs. Care of the stoma is
extremely important, since it is the person’s only way to
get air to the lungs. After a laryngectomy, a healthcare
professional will teach the laryngectomee and his or her
caregivers how to care for the stoma.
Immediately after a laryngectomy, an alternate
method of communication such as writing notes, gestur-
ing, or pointing must be used. A partial laryngectomy
patient will gradually regain some speech several weeks
after the operation, but the voice may be hoarse, weak, and
strained. A speech pathologist will work with a complete
laryngectomee to establish new ways of communicating.
There are three main methods of vocalizing after a
total laryngectomy. In esophageal speech the laryngec-

Many patients resume daily activities after surgery.
Special precautions must be taken during showering or
shaving. Special instruction and equipment is also
required for those who wish to swim or water ski, as it is
dangerous for water to enter the windpipe and lungs
through the stoma.
Regular follow-up visits are important following
treatment for cancer of the larynx because there is a high-
er-than-average risk of developing a new cancer in the
mouth, throat, or other regions of the head or neck. Many
self-help and support groups are available to help
patients meet others who face similar problems.
Risks
Laryngectomy is often successful in curing early
stage cancers. However it does cause lifestyle changes.
Laryngectomees must learn new ways of speaking. They
must be continually concerned about the care of their
stoma. Serious infections can occur if water or other for-
eign material enters the lungs through an unprotected
stoma. Also, women who undergo partial laryngectomy
or who learn some types of artificial speech will have a
deep voice similar to that of a man. For some women this
presents psychological challenges.
Normal results
Ideally, removal of the larynx will remove all cancer-
ous material. The person will recover from the operation,
make lifestyle adjustments, and return to an active life.
Abnormal results
Sometimes cancer has spread to surrounding tissues
and it is necessary to remove lymph nodes, parts of the

Definition
Laryngoscopy refers to a procedure used to view the
inside of the larynx (the voice box).
KEY TERMS
Larynx—Also known as the voice box, the larynx
is composed of cartilage that contains the appara-
tus for voice production. This includes the vocal
cords and the muscles and ligaments that move
the cords.
Lymph nodes—Accumulations of tissue along a
lymph channel, which produce cells called lym-
phocytes that fight infection.
Tracheostomy—A surgical procedure in which an
artificial opening is made in the trachea (wind-
pipe) to allow air into the lungs.
KEY TERMS
Endoscopic tube—A tube that is inserted into a
hollow organ permitting a physician to see the
inside it.
Description
The purpose and advantage of seeing inside the lar-
ynx is to detect tumors, foreign bodies, nerve or structur-
al injury, or other abnormalities. Two methods allow the
larynx to be seen directly during the examination. In one,
a flexible tube with a fiber-optic device is threaded
through the nasal passage and down into the throat. The
other method uses a rigid viewing tube passed directly
from the mouth, through the throat, into the larynx. A
light and lens affixed to the endoscope are used in both
methods. The endoscopic tube may also be equipped to

Purpose
Laxatives are used to prevent or treat constipation.
They are also used to prepare the bowel for an examina-
tion or surgical procedure.
Description
Laxatives work in different ways, by stimulating
colon movement, adding bulk to the contents of the
colon, or drawing fluid or fat into the intestine. Some
laxatives work by combining these functions.
Bisacodyl
Bisacodyl is a non-prescription stimulant laxative. It
reduces short-term constipation and is also used to pre-
pare the colon or rectum for an examination or surgical
procedure. The drug works by stimulating colon move-
ment (peristalsis); constipation is usually relieved within
15 minutes to one hour after administration of a supposi-
tory form and in 6 to 12 hours after taking the drug orally.
Calcium polycarbophil
Calcium polycarbophil is a non-prescription bulk-
forming laxative that is used to reduce both constipation
and diarrhea. It draws water to the intestine, enlarging the
size of the colon and thereby stimulating movement. It
reduces diarrhea by taking extra water away from the stool.
This drug should relieve constipation in 12 to 24 hours and
have maximum effect in three days. Colitis patients should
see a reduction in diarrhea within one week.
Docusate calcium/docusate sodium
Docusate, a non-prescription laxative, helps a
patient avoid constipation by softening the stool. It works
by increasing the penetration of fluids into the stool by

pository or enema).
Bisacodyl
• Adults or children over 12 years: 5 to 15 mg taken by
mouth in morning or afternoon (up to 30 mg for surgi-
cal or exam preparation).
•Adult (rectal): 10 mg.
• Children age 2 to 11 years: 10 mg rectally as single
dose.
• Children over 3 years: 5 to 10 mg by mouth as single
dose.
• Children under 2 years: 5 mg rectally as single dose.
Calcium polycarbophil
• Adult: 1 g by mouth every day, up to four times a day as
needed (not to exceed 6 g by mouth in a 24-hour time
period).
• Children age 6 to 12 years: 500 mg by mouth twice a day
as needed (not to exceed 3 g in a 24-hour time period).
• Children age 3 to 6 years: 500 mg twice a day by
mouth, as needed (not to exceed 1.5 g in a 24-hour time
period).
Docusate
• Adult (docusate sodium): 50 to 300 mg by mouth per
day.
• Adult (docusate calcium or docusate potassium): 240
mg by mouth as needed.
• Adult (docusate sodium enema): 5 ml.
• Children over 12 years (docusate sodium enema): 2 ml.
• Children age 6 to 12 years (docusate sodium): 40 to 120
mg by mouth per day.
• Children age 3 to 6 years (docusate sodium): 20 to 60

Laxatives
• Children: Parents should ask their doctor as dosage is
based on weight. Black Draught is not to be used by
children.
• Children age 1 month to 1 year (Senokot): 1.25 to 2.5
ml of syrup at bedtime.
Precautions
The doctor should be informed of any prior allergic
drug reaction, especially prior reactions to any laxatives.
Pregnancy is also a concern. Animal studies have shown
laxatives to have adverse effects on pregnancy, but no
human studies regarding pregnancy are currently avail-
able. These drugs are only given in pregnancy after the
risks to the fetus have been taken under consideration.
Nursing mothers should use caution and consult their
doctor before receiving these drugs.
Bisacodyl should not be administered to patients
with rectal fissures, abdominal pain, nausea, vomiting,
appendicitis, abdominal surgery, ulcerated hemorrhoids,
acute hepatitis, fecal impaction, or blockage in the biliary
tract. Calcium polycarbophil should not be given to any-
one with a gastrointestinal blockage (obstruction).
Both psyllium and docusate calcium/docusate sodi-
um should be avoided by patients with intestinal block-
age, fecal impaction, or nausea and vomiting. Lactulose
should be avoided by patients who are elderly, have dia-
betes mellitus, eat a low galactose diet, or whose general
health is poor.
Finally, senna/senokot is inadvisable for patients
with congestive heart failure, gastrointestinal bleeding,

Side effects include:
• bitter taste in the mouth
• irritated throat
• nausea
• cramps
• diarrhea
• loss of appetite
• rash
Lactulose
Common side effects include:
• nausea
•vomiting
• loss of appetite
•abdominal cramping
• bloating
• belching
• diarrhea
Psyllium
Common side effects include:
• nausea
•vomiting
• loss of appetite
• diarrhea
Less common side effects include:
GALE ENCYCLOPEDIA OF CANCER
580
Laxatives
•abdominal cramping
• blockage of the esophagus or intestine
Senna/senokot

levels are the amounts of certain acids, bases, and
salts. Abnormal levels of certain electrolyes can be
life-threatening.
Encephalopathy—a brain disease.
Peristalsis—Wave-like movement of the colon to
pass feces along.
Tetany—Muscle spasms that can be life-threatening.
• Psyllium: Cardiac glycosides, oral anticoagulants, and
salicylates.
• Senna/senokot: Disulfiram should never be taken with
this drug. Also, senna/senokot lowers the absorption of
other drugs taken by mouth.
Rhonda Cloos, R.N.
Leiomyosarcoma
Definition
Leiomyosarcoma is cancer that consists of smooth
muscle cells and small cell sarcoma tumor. The cancer
begins in smooth muscle cells that grow uncontrollably
and form tumors.
Description
Leiomyosarcomas can start in any organ that con-
tains smooth muscle, but can be found in the walls of the
stomach, large and small intestines, esophagus, uterus, or
deep within the abdomen (retroperitoneal). But for per-
spective, smooth muscle cancers are quite rare: Less than
1% of all cancers are leiomyosarcomas. Very rarely,
leiomyosarcomas begin in blood vessels or in the skin.
Most leiomyosarcomas are in the stomach. The sec-
ond most common site is the small bowel, followed by
the colon, rectum, and esophagus.

toms include:
• painless lump or mass
• painful swelling
•abdominal pain
• weight loss
• nausea and vomiting
Diagnosis
Some patients who have leiomyosarcomas may be
visiting the doctor because they have discovered a lump
or mass or swelling on a body part. Others have symp-
toms related to the internal organ that is affected by the
leiomyosarcoma. For example, a tumor in the stomach
may cause nausea, feelings of fullness, internal bleeding,
and weight loss. The patient’s doctor will take a detailed
medical history to find out about the symptoms. The his-
tory is followed by a complete physical examination with
special attention to the suspicious symptom or body part.
Depending on the location of the tumor, the doctor
may order imaging studies such as x ray, computed
tomography (CT) scan, and magnetic resonance imag-
ing (MRI) to help determine the size, shape, and exact
location of the tumor. A biopsy of the tumor is necessary
to make the definitive diagnosis of leiomyosarcoma. The
tissue sample is examined by a pathologist (specialist in
the study of diseased tissue).
Types of biopsy
The type of biopsy done depends on the location of
the tumor. For some small tumors, the doctor may per-
form an excisional biopsy, removing the entire tumor and
a margin of surrounding normal tissue. Most often, the

Treatment
Treatment for leiomyosarcoma varies depending on
the location of the tumor, its size and grade, and the
extent of its spread. Treatment planning also takes into
account the patient’s age, medical history, and general
health.
Leiomyosarcomas on the arms and legs may be
treated by amputation (removal of the affected limb) or
by limb-sparing surgery to remove the tumor. These
tumors may also be treated with radiation therapy,
chemotherapy, or a combination of both.
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Leiomyosarcoma
Surgery to remove a leiomyosarcoma in the tissue near a kid-
ney. (Custom Medical Stock Photo. Reproduced by permission.)
Generally, tumors inside the abdomen are surgically
removed. The site, size, and extent of the tumor deter-
mine the type of surgery performed. Leiomyosarcomas
of organs in the abdomen may also be treated with radia-
tion and chemotherapy.
Side effects
The surgical treatment of leiomyosarcoma carries
risks related to the surgical site, such as loss of function
resulting from amputation or from nerve and/or muscle
loss. There also are risks associated with any surgical
procedure, such as reactions to general anesthesia or
infection after surgery.
The side effects of radiation therapy depend on the
site being radiated. Radiation therapy can produce side

Fatigue is one of the most common complaints dur-
ing cancer treatment and recovery. Many patients benefit
from learning energy-conserving approaches to accom-
plish their daily activities. They should be encouraged to
QUESTIONS
TO ASK THE DOCTOR
• What stage is the leiomyosarcoma?
• What are the recommended treatments?
• What are the side effects of the recommended
treatment?
• Is treatment expected to cure the disease or
only to prolong life?
rest when tired and take breaks from strenuous activities.
Planning activities around times of day when energy is
highest is often helpful. Mild exercise, small, frequent
nutritious snacks, and limiting physical and emotional
stress also help to combat fatigue.
Depression,emotional distress, and anxiety associ-
ated with the disease and its treatment may respond to
counseling from a mental health professional. Many
cancer patients and their families find participation in
mutual aid and group support programs helps to relieve
feelings of isolation and loneliness. By sharing prob-
lems with others who have lived through similar diffi-
culties, patients and families can exchange ideas and
coping strategies.
Clinical trials
Several clinical studies were underway as of 2001.
For example, doctors at Memorial Sloan-Kettering Can-
cer Center were using specific chemotherapeutic drugs to

BOOKS
Murphy, Gerald P. et al. American Cancer Society Textbook of
Clinical Oncology Second Edition. Atlanta, GA: The
American Cancer Society, Inc., 1995.
Otto, Shirley E. Oncology Nursing. St. Louis, MO: Mosby,
1997.
Pelletier, Kenneth R. The Best of Alternative Medicine. New
York, NY: Simon & Schuster, 2000.
PERIODICALS
Schwartz, L. B. et al. “Leiomyosarcoma: Clinical Presenta-
tion.” American Journal of Obstetrics and Gynecology
168(1)(January 1993):180-183.
Ishida, J. et al. “Primary Leiomyosarcoma of the Greater
Omentum.” Journal Of Clinical Gastroenterology 28(2)
(March 1999): 167-170.
Antonescru, C. R. et al. “Primary Leiomyosarcoma of Bone: A
Clinicopathologic, Immunohistochemical, and Ultrastruc-
tural Study of 33 Patients and a Literature Review.” Amer-
ican Journal of Surgical Pathology 21(11) (November
1997): 1281-1294.
KEY TERMS
Biopsy—The surgical removal and microscopic
examination of living tissue for diagnostic purposes.
Chemotherapy—Treatment of cancer with syn-
thetic drugs that destroy the tumor either by
inhibiting the growth of cancerous cells or by
killing them.
Oncologist—A doctor who specializes in cancer
medicine.
Pathologist—A doctor who specializes in the

cers, acute leukemias, and Burkitt’s lymphoma. Fluo-
rouracil is used in combination with leucovorin to treat
colorectal cancer. When leucovorin and methotrexate are
used together, this therapy is often called leucovorin res-
cue because leucovorin rescues healthy cells from the
toxic effects of methotrexate. In patients with colorectal
cancer, however, leucovorin increases the anti-cancer
effect of fluorouracil.
Leucovorin is also used to treat megaloblastic ane-
mia, a blood disorder in which red blood cells become
larger than normal, and to treat accidental overdoses of
drugs like methotrexate.
Description
Leucovorin is a faster acting and stronger form of
folic acid, and has been used for several decades. Folic
acid is also known as vitamin B9, and is needed for the
normal development of red blood cells. In humans,
dietary folic acid must be reduced metabolically to
tetrahydrofilic acid (THFA) to exert its vital biochemical
GALE ENCYCLOPEDIA OF CANCER
584
Leucovorin
functions. The coenzyme THFA and its subsequent other
cofactors participate in many important reactions includ-
ing DNA synthesis.
Leucovorin rescue
Some chemotherapy drugs, such as methotrexate
(Mexate, Folex), work by preventing cells from using
folic acid. Methotrexate therapy causes cancer cells to
develop a folic acid deficiency and die. However, normal

Precautions
Patients with anemia, or any type of blood disorder,
should tell their doctor. Leucovorin can treat only anemia
caused by folic acid deficiency. Patients with other types
of anemia should not take leucovorin. The effect of leu-
covorin on the fetus is not known, and it is not known if
the drug is found in breast milk. Leucovorin should
therefore be used with caution during pregnancy. Elderly
patients treated with leucovorin and fluorouracil for
KEY TERMS
Folic acid—Vitamin B9.
Leucovorin rescue—A cancer therapy where the
drug leucovorin protects healthy cells from toxic
chemotherapy.
advanced colorectal cancer are at greater risk for devel-
oping severe side effects.
Side effects
The vast majority of patients do not experience side
effects from leucovorin therapy. Side effects are usually
caused by the patient’s chemotherapy, not by leucovorin.
In rare cases, however, some patients can develop aller-
gic reactions to the drug. These include skin rash, hives,
and itching.
Interactions
Although there are no listed drug interactions for
leucovorin, patients should tell their doctor about any
over the counter or prescription medication they are tak-
ing, particularly medication that can cause seizures.
Alison McTavish, M.Sc.
Leukapheresis see Pheresis

cer. Some other medications, including cytarabine, flu-
darabine, carmustine and fluorouracil in conjunction
with levamisole. The disease may appear years after the
administration of methotrexate. Although rare, the inci-
dence of leukoencephalopathy is increasing, as stronger
drugs are developed and increased survival times allow
time for the side effects of the treatments to appear.
A devastating type of leukoencephalopathy, called
multifocal, or disseminated, necrotizing leukoen-
cephalopathy, has been shown to occur primarily when
methotrexate or cytarabine therapy is used in conjunction
with a large cumulative dose of whole head irradiation.
This disease is characterized by multiple sites of necrosis
of the nerve cells in the white matter of the brain, involv-
ing both the myelin coating and the nerve cells them-
selves. Although some patients may stabilize, the course
is usually progressive, with patients experiencing relent-
less mental deterioration and, finally, death.
Although leukoencephalopathy is primarily associ-
ated with methotrexate therapy, this disease has also been
observed in association with other chemotherapeutic
drugs (like intrathecal cytarabine) and occasionally been
reported in association with cancers that have not yet
been treated.
Another, particularly lethal, type of leukoen-
cephalopathy called progressive multifocal leukoen-
cephalopathy (PML) is an opportunistic infection that
occurs in cancer patients who experience long-term
immunosuppression as a result of the cancer (as in
leukemia or lymphoma) or as a result of chemotherapy

stood. Long-term immunosuppression somehow appears
to create an environment where the JC virus that inhabits
most healthy human kidneys can mutate into a form that
gains access to the brain. When in the brain, the virus
infects and kills the cells that produce the myelin that
forms a protective coating around the nerve.
Treatments
Unfortunately, there is no cure for any form of
leukoencephalopathy, and no treatments approved.
Although some medications have shown some effect
against the deterioration involved in this disease, those
identified have been highly toxic themselves, and none
so far have been effective enough to justify use. The
treatment of people with this disorder, therefore, tends to
concentrate on alleviating discomfort.
Since there are no effective treatments, prevention
must be emphasized. As the risks of certain treatment
choices have become more defined, physicians must pur-
sue careful treatment planning to produce optimal chance
of tumor eradication while avoiding increased risk of the
onset of a fatal and incurable side effect. This is especial-
ly true in children. The cases observed have largely been
in children, which implies that the developing brain is at
higher risk of developing treatment-associated leukoen-
cephalopathy.
Alternative and complementary therapies
There are no commonly used alternative treatments,
although since the disease is incurable, there is little risk
GALE ENCYCLOPEDIA OF CANCER
586

Purpose
Leuprolide acetate is used primarily to counter the
symptoms of advanced prostate cancer in men when
surgery to remove the testes or estrogen therapy is not an
option or is unacceptable to the patient. It is often used to
ease the pain and discomfort of women suffering from
endometrosis, advanced breast cancer, or advanced
ovarian cancer.
Two less common uses of this drug are the treatment
of anemia caused by bleeding uterine fibroids, and the
treatment of early onset (precocious) puberty.
Description
Leuprolide acetate is a man-made protein that mim-
ics many of the actions of gonadotropin releasing hor-
mone. In men, it decreases blood levels of the male hor-
mone testosterone. In women, it decreases blood levels
of the female hormone estrogen.
Recommended dosage for prostate cancer
In men, there are three methods of dosing: daily
injections, a monthly injection, or an annual implanted
capsule. In the case of daily injections, 1 mg of leupro-
lide acetate is injected under the skin (subcutaneously).
In the case of monthly injections, an implanted capsule
that contains 7.5 mg of leuprolide acetate is injected into
a muscle. In the case of an annual implanted capsule, the
capsule contains 72 mg of leuprolide acetate. Both the
monthly and the annual capsules are specially designed
to slowly release the drug into the patient’s bloodstream
over the specified time. The monthly capsule dissolves
completely over the course of the month. The annual

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587
Leuprolide acetate