Peutz-Jeghers Syndrome
Peutz-Jeghers syndrome
Definition
Peutz-Jeghers syndrome (PJS) is named after two doctors who first studied and described it in 1921. It is an association of three very specific conditions in any one person. The first condition is the appearance of freckles on parts of the body where freckles are not normally found. The second condition is the presence of multiple gastrointestinal polyps. The third condition is a risk, greater than the risk seen in the general population, of developing certain kinds of cancers.
Description
The freckles associated with PJS are dark brown, dark blue, or greenish black. In almost all people with PJS, these freckles are present at birth on the lining of the cheeks inside the mouth. By the time most children reach one or two years old, freckles develop around the lips, nostrils, eyes, anus, and genitals. This is in contrast to ordinary freckles, which are absent at birth and rarely develop in these locations. The freckles seen in PJS are sometimes called macules (discolored spot or patch on the skin of various colors, sizes, and shapes), or areas of hyperpigmentation (increased pigmentation of the skin).
Some people with PJS also have these freckles on the palms of their hands or feet or on their fingertips. Freckles may merge together. The freckles on the skin often fade or disappear by adolescence, but the freckles inside the mouth generally remain throughout the person's life.
Gastrointestinal polyps can develop in children as young as one or two years old. The age at which polyps appear and the number of polyps vary widely from patient to patient. The polyps can occur in infants and cause spasms and pain in the abdomen. On average, polyps appear by the time a child with PJS is 10 years old. There may be anywhere from dozens to hundreds of polyps throughout the gastrointestinal tract. For this reason, PJS is sometimes called polyposis, which means "too many polyps." Most PJS polyps occur in the small intestine, but they can also develop in the esophagus, stomach, and colon. In some people with PJS, polyps have been found in the mouth or nose.
The polyps seen in PJS have a unique structure. They consist of overgrowths of normal tissue that smooth muscle bands of the stomach and instestines run through. This kind of overgrowth is called a hamartoma. Consequently, PJS is sometimes called hamartomatous intestinal polyposis. A hamartoma is a non-cancerous tumor, and hamartomatous polyps are not cancerous. However, they can take up too much space, causing obstruction, pain, and even bleeding. They can also become cancerous, or malignant, if a genetic change results in uncontrolled cell growth.
It is this potential for malignant change that increases cancer risk in people with PJS. As might be expected, the gastrointestinal tract is the most common site for cancer in people with PJS. The small intestine, stomach, gallbladder, pancreas, colon, and rectum are all susceptible. However, cancer can also occur outside the gastrointestinal tract. When this happens, the sites most likely to be involved are the breasts, ovaries, uterus, cervix, or testicles.
PJS does not affect intelligence or behavior.
Genetic profile
Researchers have identified the gene responsible for about seven out of ten PJS cases. The gene is named STK11, and it is located at the 19p13 site on chromosome 19. In some older studies, the same gene is referred to as LKB1. As of 2001, researchers have connected more than 50 different STK11 mutations to cases of PJS.
However, some cases do not appear to be connected to STK11. As a result, PJS qualifies as a genetically heterogeneous condition; this means that it has more than one known genetic cause. Research continues in order to locate the genes involved in the three out of ten cases not related to STK11.
When linked to STK11, PJS is an autosomal dominant disorder. This means that the condition occurs even when an individual inherits only one abnormal copy of STK11 from either parent. In some people with PJS, the condition is limited to freckles on the lining of the cheeks inside the mouth. Many of these people also have gastrointestinal polyps. One abnormal copy of STK11 also increases a person's risk of developing the kinds of cancer associated with PJS.
However, since only one abnormal copy of STK11 is needed to cause PJS, most people with the condition still have one normal copy of the gene. One normal copy is usually enough to protect against the kinds of cancer associated with PJS. This is because STK11 is a tumor suppressor gene. A properly working tumor suppressor gene makes a product that controls cell growth. Since cancer is the result of uncontrolled cell growth, tumor suppressors prevent cancer. Even one working copy of STK11 protects against cancer.
The reason people with PJS have an increased risk of developing cancer is that one STK11 gene is already abnormal at birth. If damage to the normal STK11 gene occurs later, the ability to control cell growth is lost, leading to the kinds of cancers associated with PJS.
Damage to normal genes can occur in anyone. However, it generally takes less time to damage one gene than two genes. Therefore, people with PJS are likely to develop cancer at earlier ages than are people born with two normal STK11 genes.
About half of all PJS cases occur because a child inherits a changed gene from a parent with PJS. The other half are due to a mutation in the cell from which the child develops. A person born with one abnormal gene can pass that gene on to the next generation. One out of two of this person's children will inherit the gene. In addition, if PJS is inherited, each parent or sibling of the affected person has a one out of two chance of carrying the gene.
Demographics
PJS occurs in about one out of 25,000 people. It affects males and females of all races and ethnic groups. The particular genetic mutation may differ among groups and even among families within a group.
Signs and symptoms
The first sign of PJS, freckling inside the mouth or in unusual places, generally appears in infants. Polyps usually begin causing symptoms by age 10. Polyps make themselves known in a variety of ways. They can cause abdominal pain or intestinal bleeding. Sometimes the blood loss leads to anemia (a condition where there is a reduction in circulating red blood cells, the amount of hemoglobin, or the volume of packed red cells). Polyps sometimes protrude outside the rectum or obstruct the gastrointestinal tract. Untreated obstructions can be fatal.
Tumors may appear in childhood. Children as young as six may develop a particular kind of ovarian or testicular tumor that causes early puberty. Affected boys sometimes begin to develop breasts. These tumors can be non-cancerous, but they have the potential to become malignant.
A few patients develop malignant tumors in the first decade of life. Other patients have stomach, breast, or cervical cancer before age 30. The specific form of cervical cancer is extremely rare in the general population.
Diagnosis
Because the peculiar freckling seen in PJS is present so early, doctors familiar with the condition may suspect PJS even before other symptoms occur. This is ideal, since early diagnosis greatly improves the prognosis.
Many children or young adults come to medical attention due to the pain, bleeding, or anemia caused by polyps. Doctors can confirm the presence of multiple polyps using a variety of methods. Noninvasive methods include ultrasound and x ray techniques. Invasive methods use a tube and an optical system to conduct an internal inspection of the gastrointestinal tract. These methods include endoscopy, enteroscopy, and colonoscopy, all of which involve entry to the gastrointestinal tract through an existing body orifice. Laparoscopy is another invasive method; it involves entering the gastrointestinal tract through an incision in the abdomen. All invasive methods allow for removal of polyps found during the exam. Once the polyps are removed and examined, their unique structure and large number lead to diagnosis of PJS. The average age at PJS diagnosis is 17.
Freckles and polyps occur in more than 95% of people with PJS. Sometimes, though, the freckles fade before symptoms of polyps appear. It is important to take a medical history in order to determine if freckles were present on the skin earlier in life. The doctor should also examine the lining of the cheeks inside the mouth, where freckles are likely to remain throughout life.
The number and intensity of the freckles do not predict the severity of gastrointestinal symptoms or the risk of developing cancer. Any patient diagnosed with PJS needs regular cancer screening.
The presence of the rare cervical cancer, ovarian tumor, or testicular tumor associated with PJS leads to diagnosis in some patients.
A family history of PJS is suspicious but not required for diagnosis, since PJS can occur as a new mutation. Once PJS has occurred in a family, parents, siblings, and children of the affected person should seek medical attention.
Genetic testing is available to confirm clinical diagnosis or to determine if a person carries an abnormal STK11 gene. Using a swab, cells are removed from the lining of the cheeks inside the mouth. DNA is extracted and analyzed. The test confirms PJS if analysis reveals an STK11 mutation. However, the test cannot rule out PJS if an STK11 mutation is not found, since some cases are due to other genetic causes.
Prenatal diagnosis of PJS is possible only if the family's specific STK11 mutation has previously been identified. Prenatal testing is done by amniocentesis or chorionic villus sampling. Amniocentesis involves removal of a small amount of amniotic fluid from the uterus. Chorionic villus sampling involves removal of a small sample of placental tissue. In either case, DNA is extracted from sample cells and analyzed.
Even without genetic testing, diagnosis of PJS is fairly straightforward. Although several other conditions cause multiple intestinal polyps or hyperpigmentation, the distinctive structure of PJS polyps and the unusual location of PJS freckles eliminate other conditions from consideration.
Treatment and management
For people with a family history of PJS, treatment and management of the condition may begin even before diagnosis. If PJS freckles do not appear at birth and if there are no symptoms of polyps, affected families may desire genetic testing for their children.
For most genetic conditions, testing is delayed until children are old enough to understand the disease, its consequences, and the advantages and disadvantages of genetic screening. However, since PJS can affect children under the age of 10, any delay could be risky. Therefore, it is appropriate for families with PJS to consider genetic testing for their children. Children who do carry an STK11 mutation can begin a preventive care program immediately, and children who do not carry an STK11 mutation can avoid unnecessary intervention.
The decision to seek genetic testing requires careful consideration. A positive test for PJS cannot predict the precise age of onset, symptoms, severity, or progress of the condition. A genetic counselor can assist interested family members as they confront the medical, social, personal, and economic issues involved in genetic testing.
Parents, siblings, and children of people with STK11 mutations may not wish to undergo genetic testing. In this case, they should have a thorough clinical exam to confirm or rule out PJS. The exam includes a careful inspection for freckles. In addition, people age 10 or older require gastrointestinal screening, abdominal ultrasound, and a blood test for anemia. Males over age 10 should have a testicular exam. Females should have a pelvic exam and ultrasound, pap smear, and breast exam annually, by age 20. Women age 35 or older should have a mammogram.
For people with no family history of PJS, treatment and management usually begin when PJS is diagnosed.
In past generations, polyp complications such as intestinal obstruction or hemorrhage were a frequent cause of death in PJS patients. However, treatment of polyps is now widely available. The doctor performs a polypectomy to remove the polyps. Polypectomy may be done at the same time as endoscopy, enteroscopy, colonoscopy, or laparoscopy. Anesthesia is used to make the patient more comfortable.
To manage polyps and screen for early signs of cancer, all people who have PJS and are age 10 or older need preventive screening on a regular basis. Gastrointestinal screening is the first test, and polypectomy is performed at the same time. Also at age 10, the person begins an annual screening program that includes a blood test for anemia and a testicular exam for boys.
After age 10, gastrointestinal screening with polypectomy is performed every two years.
By age 20, annual screening is expanded to include an abdominal ultrasound for both males and females, as well as a pelvic exam and ultrasound, pap smear, and breast exam for females.
By age 35, a woman with PJS should have her first mammogram; mammograms should be repeated every two years until the woman is 50. At that time, a mammogram should be added to the annual screening program.
Polyps found during preventive screening are immediately treated by polypectomy. Preventive screening may also reveal suspicious growths in the gastrointestinal tract or outside of it. These growths require urgent medical attention, since they may be precancerous or cancerous. Diagnosis may require additional tests or biopsy. Treatment is determined on an individual basis, depending on the patient's medical condition and the nature of the growth.
Some people with PJS do not care for the appearance of their freckles. Removal of freckles using laser therapy is an available treatment option.
Many people with PJS find the preventive screening program psychologically exhausting, and young children can find it frightening. These individuals often need the ongoing support and understanding of friends, family, and community. Several organizations composed of people with PJS, their family members, and medical professionals offer additional support and information. There is also an on-line support group dedicated to PJS.
People with PJS may find it helpful to consult a genetic counselor. Genetic counselors can provide up-to-date information about PJS research, therapy, and management.
Prognosis
Early detection of PJS is the key to its prognosis. Polyps cause less pain and fewer complications when found and removed early. In addition, the patient can begin a preventive screening program at an early age. This increases the likelihood of finding suspicious growths before they become malignant.
Unless they undergo regular screening, people with PJS have a one in two chance of dying from cancer before the age of 60. Moreover, the average age of cancer death in unscreened people with PJS is 39.
Researchers are actively investigating cancer screening, prevention, and treatment methods. In the meantime, regular preventive screening may reduce the illness and premature death associated with PJS.
Resources
BOOKS
Rimoin, David L., et al., eds. Emery and Rimoin's Principles and Practice of Medical Genetics. Third Edition. New York: Churchill Livingstone, 1996.
Sybert, Virginia P. Genetic Skin Disorders. New York: Oxford University Press, 1997.
PERIODICALS
Boardman, Lisa A., et al. "Genetic Heterogeneity in Peutz-Jeghers syndrome." Human Mutation 16, no. 1 (2000):23-30.
Hemminki, Akseli. "The molecular basis and clinical aspects of Peutz-Jeghers syndrome." Cellular and Molecular Life Sciences 55 (2000):735-750.
Westerman, Anne Marie, et al. "Peutz-Jeghers syndrome: 78-year follow-up of the original family." The Lancet 353 (April 1999):1211-1215.
ORGANIZATIONS
Genetic Alliance. 4301 Connecticut Ave. NW, #404, Washington, DC 20008-2304. (800) 336-GENE (Helpline) or (202) 966-5557. Fax: (888) 394-3937 info@geneticalliance. <http://www.geneticalliance.org>.
Hereditary Colon Cancer Association (HCCA). 3601 N 4th Ave., Suite 201, Sioux Falls, SD 57104. (800) 264-6783. <http://hereditarycc.org>.
IMPACC (Intestinal Multiple Polyposis and Colorectal Cancer). PO Box 11, Conyngham, PA 18219. (570) 788-1818.
International Peutz-Jeghers Support Group. Johns Hopkins Hospital, Blalock 1008, 600 North Wolfe St., Baltimore, MD 21287-4922.
WEBSITES
Association of Cancer Online Resources. Peutz-Jeghers Syndrome Online Support Group. December 23, 2002. <http://www.acor.org>.
CancerNet. 2001. <http://www.cancernet.nci.nih.gov>.
GeneClinics. 2001. <http://www.geneclinics.org>.
GeneTests. 2001. <http://www.genetests.org>.
Network for Peutz-Jeghers and Juvenile Polyposis Syndrome. 2001. <http://www.epigenetic.org>.
OMIM: Online Mendelian Inheritance in Man. http://www3.ncbi.nlm.nih.gov/omim
Avis L. Gibons
Peutz-Jeghers syndrome
Peutz-Jeghers syndrome
Definition
Peutz-Jeghers syndrome (PJS) is named after two doctors who first studied and described it in 1921. It is an association of three very specific conditions in any one person. The first condition is the appearance of freckles on parts of the body where freckles are not normally found. The second condition is the presence of multiple gastrointestinal polyps. The third condition is a risk, greater than the risk seen in the general population, of developing certain kinds of cancers.
Description
The freckles associated with PJS are dark brown, dark blue, or greenish black. In almost all people with PJS, these freckles are present at birth on the lining of the cheeks inside the mouth. By the time most children reach one or two years old, freckles develop around the lips, nostrils, eyes, anus, and genitals. This is in contrast to ordinary freckles, which are absent at birth and rarely develop in these locations. The freckles seen in PJS are sometimes called macules (discolored spot or patch on the skin of various colors, sizes, and shapes), or areas of hyperpigmentation (increased pigmentation of the skin).
Some people with PJS also have these freckles on the palms of their hands or feet or on their fingertips. Freckles may merge together. The freckles on the skin often fade or disappear by adolescence, but the freckles inside the mouth generally remain throughout the person's life.
Gastrointestinal polyps can develop in children as young as one or two years old. The age at which polyps appear and the number of polyps vary widely from patient to patient. The polyps can occur in infants and cause spasms and pain in the abdomen. On average, polyps appear by the time a child with PJS is 10 years old. There may be anywhere from dozens to hundreds of polyps throughout the gastrointestinal tract. For this reason, PJS is sometimes called polyposis, which means "too many polyps." Most PJS polyps occur in the small intestine, but they can also develop in the esophagus, stomach, and colon. In some people with PJS, polyps have been found in the mouth or nose.
The polyps seen in PJS have a unique structure. They consist of overgrowths of normal tissue that smooth muscle bands of the stomach and instestines run through. This kind of overgrowth is called a hamartoma. Consequently, PJS is sometimes called hamartomatous intestinal polyposis. A hamartoma is a non-cancerous tumor, and hamartomatous polyps are not cancerous. However, they can take up too much space, causing obstruction, pain, and even bleeding. They can also become cancerous, or malignant, if a genetic change results in uncontrolled cell growth.
It is this potential for malignant change that increases cancer risk in people with PJS. As might be expected, the gastrointestinal tract is the most common site for cancer in people with PJS. The small intestine, stomach, gallbladder, pancreas, colon, and rectum are all susceptible. However, cancer can also occur outside the gastrointestinal tract. When this happens, the sites most likely to be involved are the breasts, ovaries, uterus, cervix, or testicles.
PJS does not affect intelligence or behavior.
Genetic profile
Researchers have identified the gene responsible for about seven out of ten PJS cases. The gene is named STK11, and it is located at the 19p13 site on chromosome 19. In some older studies, the same gene is referred to as LKB1. As of 2001, researchers have connected more than 50 different STK11 mutations to cases of PJS.
However, some cases do not appear to be connected to STK11. As a result, PJS qualifies as a genetically heterogeneous condition; this means that it has more than one known genetic cause. Research continues in order to locate the genes involved in the three out of ten cases not related to STK11.
When linked to STK11, PJS is an autosomal dominant disorder. This means that the condition occurs even when an individual inherits only one abnormal copy of STK11 from either parent. In some people with PJS, the condition is limited to freckles on the lining of the cheeks inside the mouth. Many of these people also have gastrointestinal polyps. One abnormal copy of STK11 also increases a person's risk of developing the kinds of cancer associated with PJS.
However, since only one abnormal copy of STK11 is needed to cause PJS, most people with the condition still have one normal copy of the gene. One normal copy is usually enough to protect against the kinds of cancer associated with PJS. This is because STK11 is a tumor suppressor gene. A properly working tumor suppressor gene makes a product that controls cell growth. Since cancer is the result of uncontrolled cell growth, tumor suppressors prevent cancer. Even one working copy of STK11 protects against cancer.
The reason people with PJS have an increased risk of developing cancer is that one STK11 gene is already abnormal at birth. If damage to the normal STK11 gene occurs later, the ability to control cell growth is lost, leading to the kinds of cancers associated with PJS.
Damage to normal genes can occur in anyone. However, it generally takes less time to damage one gene than two genes. Therefore, people with PJS are likely to develop cancer at earlier ages than are people born with two normal STK11 genes.
About half of all PJS cases occur because a child inherits a changed gene from a parent with PJS. The other half are due to a mutation in the cell from which the child develops. A person born with one abnormal gene can pass that gene on to the next generation. One out of two of this person's children will inherit the gene. In addition, if PJS is inherited, each parent or sibling of the affected person has a one out of two chance of carrying the gene.
Demographics
PJS occurs in about one out of 25,000 people. It affects males and females of all races and ethnic groups. The particular genetic mutation may differ among groups and even among families within a group.
Signs and symptoms
The first sign of PJS, freckling inside the mouth or in unusual places, generally appears in infants. Polyps usually begin causing symptoms by age 10. Polyps make themselves known in a variety of ways. They can cause abdominal pain or intestinal bleeding. Sometimes the blood loss leads to anemia (a condition where there is a reduction in circulating red blood cells, the amount of hemoglobin, or the volume of packed red cells). Polyps sometimes protrude outside the rectum or obstruct the gastrointestinal tract. Untreated obstructions can be fatal.
Tumors may appear in childhood. Children as young as six may develop a particular kind of ovarian or testicular tumor that causes early puberty. Affected boys sometimes begin to develop breasts. These tumors can be non-cancerous, but they have the potential to become malignant.
A few patients develop malignant tumors in the first decade of life. Other patients have stomach, breast, or cervical cancer before age 30. The specific form of cervical cancer is extremely rare in the general population.
Diagnosis
Because the peculiar freckling seen in PJS is present so early, doctors familiar with the condition may suspect PJS even before other symptoms occur. This is ideal, since early diagnosis greatly improves the prognosis.
Many children or young adults come to medical attention due to the pain, bleeding, or anemia caused by polyps. Doctors can confirm the presence of multiple polyps using a variety of methods. Noninvasive methods include ultrasound and x ray techniques. Invasive methods use a tube and an optical system to conduct an internal inspection of the gastrointestinal tract. These methods include endoscopy, enteroscopy, and colonoscopy, all of which involve entry to the gastrointestinal tract through an existing body orifice. Laparoscopy is another invasive method; it involves entering the gastrointestinal tract through an incision in the abdomen. All invasive methods allow for removal of polyps found during the exam. Once the polyps are removed and examined, their unique structure and large number lead to diagnosis of PJS. The average age at PJS diagnosis is 17.
Freckles and polyps occur in more than 95% of people with PJS. Sometimes, though, the freckles fade before symptoms of polyps appear. It is important to take a medical history in order to determine if freckles were present on the skin earlier in life. The doctor should also examine the lining of the cheeks inside the mouth, where freckles are likely to remain throughout life.
The number and intensity of the freckles do not predict the severity of gastrointestinal symptoms or the risk of developing cancer. Any patient diagnosed with PJS needs regular cancer screening.
The presence of the rare cervical cancer, ovarian tumor, or testicular tumor associated with PJS leads to diagnosis in some patients.
A family history of PJS is suspicious but not required for diagnosis, since PJS can occur as a new mutation. Once PJS has occurred in a family, parents, siblings, and children of the affected person should seek medical attention.
Genetic testing is available to confirm clinical diagnosis or to determine if a person carries an abnormal STK11 gene. Using a swab, cells are removed from the lining of the cheeks inside the mouth. DNA is extracted and analyzed. The test confirms PJS if analysis reveals an STK11 mutation. However, the test cannot rule out PJS if an STK11 mutation is not found, since some cases are due to other genetic causes.
Prenatal diagnosis of PJS is possible only if the family's specific STK11 mutation has previously been identified. Prenatal testing is done by amniocentesis or chorionic villus sampling. Amniocentesis involves removal of a small amount of amniotic fluid from the uterus. Chorionic villus sampling involves removal of a small sample of placental tissue. In either case, DNA is extracted from sample cells and analyzed.
Even without genetic testing, diagnosis of PJS is fairly straightforward. Although several other conditions cause multiple intestinal polyps or hyperpigmentation, the distinctive structure of PJS polyps and the unusual location of PJS freckles eliminate other conditions from consideration.
Treatment and management
For people with a family history of PJS, treatment and management of the condition may begin even before diagnosis. If PJS freckles do not appear at birth and if there are no symptoms of polyps, affected families may desire genetic testing for their children.
For most genetic conditions, testing is delayed until children are old enough to understand the disease, its consequences, and the advantages and disadvantages of genetic screening. However, since PJS can affect children under the age of 10, any delay could be risky. Therefore, it is appropriate for families with PJS to consider genetic testing for their children. Children who do carry an STK11 mutation can begin a preventive care program immediately, and children who do not carry an STK11 mutation can avoid unnecessary intervention.
The decision to seek genetic testing requires careful consideration. A positive test for PJS cannot predict the precise age of onset, symptoms, severity, or progress of the condition. A genetic counselor can assist interested family members as they confront the medical, social, personal, and economic issues involved in genetic testing.
Parents, siblings, and children of people with STK11 mutations may not wish to undergo genetic testing. In this case, they should have a thorough clinical exam to confirm or rule out PJS. The exam includes a careful inspection for freckles. In addition, people age 10 or older require gastrointestinal screening, abdominal ultrasound, and a blood test for anemia. Males over age 10 should have a testicular exam. Females should have a pelvic exam and ultrasound, pap smear, and breast exam annually, by age 20. Women age 35 or older should have a mammogram.
For people with no family history of PJS, treatment and management usually begin when PJS is diagnosed.
In past generations, polyp complications such as intestinal obstruction or hemorrhage were a frequent cause of death in PJS patients. However, treatment of polyps is now widely available. The doctor performs a polypectomy to remove the polyps. Polypectomy may be done at the same time as endoscopy, enteroscopy, colonoscopy, or laparoscopy. Anesthesia is used to make the patient more comfortable.
To manage polyps and screen for early signs of cancer, all people who have PJS and are age 10 or older need preventive screening on a regular basis. Gastrointestinal screening is the first test, and polypectomy is performed at the same time. Also at age 10, the person begins an annual screening program that includes a blood test for anemia and a testicular exam for boys.
After age 10, gastrointestinal screening with polypectomy is performed every two years.
By age 20, annual screening is expanded to include an abdominal ultrasound for both males and females, as well as a pelvic exam and ultrasound, pap smear, and breast exam for females.
By age 35, a woman with PJS should have her first mammogram; mammograms should be repeated every two years until the woman is 50. At that time, a mammogram should be added to the annual screening program.
Polyps found during preventive screening are immediately treated by polypectomy. Preventive screening may also reveal suspicious growths in the gastrointestinal tract or outside of it. These growths require urgent medical attention, since they may be precancerous or cancerous. Diagnosis may require additional tests or biopsy. Treatment is determined on an individual basis, depending on the patient's medical condition and the nature of the growth.
Some people with PJS do not care for the appearance of their freckles. Removal of freckles using laser therapy is an available treatment option.
Many people with PJS find the preventive screening program psychologically exhausting, and young children can find it frightening. These individuals often need the ongoing support and understanding of friends, family, and community. Several organizations composed of people with PJS, their family members, and medical professionals offer additional support and information. There is also an on-line support group dedicated to PJS.
People with PJS may find it helpful to consult a genetic counselor. Genetic counselors can provide up-to-date information about PJS research, therapy, and management.
Prognosis
Early detection of PJS is the key to its prognosis. Polyps cause less pain and fewer complications when found and removed early. In addition, the patient can begin a preventive screening program at an early age. This increases the likelihood of finding suspicious growths before they become malignant.
Unless they undergo regular screening, people with PJS have a one in two chance of dying from cancer before the age of 60. Moreover, the average age of cancer death in unscreened people with PJS is 39.
Researchers are actively investigating cancer screening, prevention, and treatment methods. In the meantime, regular preventive screening may reduce the illness and premature death associated with PJS.
Resources
BOOKS
Rimoin, David L., et al., eds. Emery and Rimoin's Principles and Practice of Medical Genetics. Third Edition. New York: Churchill Livingstone, 1996.
Sybert, Virginia P. Genetic Skin Disorders. New York: Oxford University Press, 1997.
PERIODICALS
Boardman, Lisa A., et al. "Genetic Heterogeneity in Peutz-Jeghers syndrome." Human Mutation 16, no. 1 (2000):23-30.
Hemminki, Akseli. "The molecular basis and clinical aspects of Peutz-Jeghers syndrome." Cellular and Molecular Life Sciences 55 (2000):735-750.
Westerman, Anne Marie, et al. "Peutz-Jeghers syndrome: 78-year follow-up of the original family." The Lancet 353 (April 1999):1211-1215.
ORGANIZATIONS
Genetic Alliance. 4301 Connecticut Ave. NW, #404, Washington, DC 20008-2304. (800) 336-GENE (Helpline) or (202) 966-5557. Fax: (888) 394-3937 info @geneticalliance. <http://www.geneticalliance.org>.
Hereditary Colon Cancer Association (HCCA). 3601 N 4th Ave., Suite 201, Sioux Falls, SD 57104. (800) 264-6783. <http://hereditarycc.org>.
IMPACC (Intestinal Multiple Polyposis and Colorectal Cancer). PO Box 11, Conyngham, PA 18219. (570) 788-1818.
International Peutz-Jeghers Support Group. Johns Hopkins Hospital, Blalock 1008, 600 North Wolfe St., Baltimore, MD 21287-4922.
WEBSITES
Association of Cancer Online Resources: Peutz-Jeghers Syndrome Online Support Group. 2001. <http://www.acor.org>.
CancerNet. 2001. <http://www.cancernet.nci.nih.gov>.
GeneClinics. 2001. <http://www.geneclinics.org>.
GeneTests. 2001. <http://www.genetests.org>.
Network for Peutz-Jeghers and Juvenile Polyposis Syndrome.
2001. <http://www.epigenetic.org>.
OMIM: Online Mendelian Inheritance in Man. <http://www3.ncbi.nlm.nih.gov/omim>.
Avis L. Gibons
Peutz-Jeghers Syndrome
Peutz-Jeghers syndrome
Definition
Peutz-Jeghers syndrome (PJS) is a rare familial cancer syndrome that causes intestinal polyps, skin freckling, and an increased risk for cancer.
Description
Peutz-Jeghers syndrome affects both males and females. The characteristic, or pathognomonic, features of PJS are unusual skin freckling and multiple polyps of the small intestine. The skin freckles, which are bluish to brown to black in color, can be found on the lips, inside the mouth, around the eyes, on the hands and feet, and on the genitals. The freckles are called benign hyperpigmented macules and do not become cancerous. The polyps in PJS are called hamartomatous polyps, and are found in the small intestine, small bowel, stomach, colon, and sometimes in the nose or bladder. Hamartomatous polyps are usually benign (not cancerous), but occasionally become malignant (cancerous). Dozens to thousands of hamartomatous polyps may develop. A person with PJS with benign hamartomatous polyps can have abdominal pain, blood in the stool, or complications such as colon obstruction or intussusception (a condition in which one portion of the intestine telescopes into another). Surgery may be required to remove the affected part of the colon. A person with PJS is at increased risk for cancer of the colon, small intestine, stomach and pancreas. Women with PJS are also at increased risk for breast and cervical cancer , and a specific type of benign ovarian tumor called SCTAT (sex cord tumors with annular tubules). Men with PJS are also at increased risk for benign testicular tumors.
Diagnosis
The diagnosis of Peutz-Jehgers syndrome can be made clinically in a person with the characteristic freckles and at least two hamartomatous polyps. A pathologist needs to confirm that the polyps are hamartomatous instead of another type of polyp. If a person has a family history of PJS, the diagnosis can be made in a person who has either freckles or hamartomatous polyps. When someone is the first person in his/her family to be diagnosed with PJS, it is important for all first-degree relatives to be carefully examined for clinical signs of PJS. About half of all persons with PJS will have family members with symptoms of PJS. Symptoms can vary between families and between members of the same family. Some family members may just have freckling and others may have more serious medical problems such as bowel obstruction or cancer diagnosis. The freckles in PJS usually appear in childhood and fade as a person gets older, so it may be necessary to look at childhood photos in an adult who is being examined for signs of PJS.
Risks
Hamartomatous polyps may be diagnosed from early childhood to later in adulthood. On average, a person with PJS develops polyps by his/her early 20s. The lifetime risk for cancer is greatly increased over the general population, and cancer may occur at an earlier age. Early and regular screening is important to try to detect any cancers at an early stage. The benign ovarian tumors in women with PJS may cause early and irregular menstruation. The benign testicular tumors in men may cause earlier growth spurts and gynecomastia (development of the male breasts).
Causes
PJS is a genetic disease caused by a mutation of a tumor suppressor gene called LBK1 (or STK11) on chromosome 19. The exact function of LBK1 is unknown at this time. PJS is inherited as an autosomal dominant condition, which means that a person with PJS has a 50% chance of passing it on to each of his/her children. Screening and/or genetic testing of family members can help sort out who has PJS or who is at risk for developing PJS. Identification of a person with PJS in a family may result in other family members with more mild symptoms being diagnosed, and then receiving appropriate screening and medical care.
Genetic Testing
Fifty percent of people clinically diagnosed with PJS will have a mutation in the LBK1/STK11 gene detected in the lab. The other half will not have a detectable mutation at that time, but may have other PJS-causing genetic mutations discovered in the future. In families where a mutation is known, family members can be tested for the same mutation. A person who tests positive for the family mutation will be diagnosed with PJS (even if he/she does not currently show signs of PJS), will need to have the recommended screening evaluations, and is able to pass on the mutation to his/her children. A person who tests negative for a known family mutation will be spared from screening, and his/her children will not be at risk for PJS. When the mutation cannot be found in a family, genetic testing is not useful, and all persons at risk for inheriting PJS will need to have screening for PJS throughout their life span.
Screening and Treatment
Regular medical examinations and special screening tests are needed in people with PJS. The age at which screening begins and the frequency of the tests is best determined by a physician familiar with PJS. Screening schedules depend on symptoms and family history. Colonoscopy , used to search for polyps in the colon, usually begins in adolescence. X rays and/or upper gastrointestinal endoscopy are used to screen for polyps in the stomach and small intestine. The goal of screening is to remove polyps before they cause symptoms or become cancerous. Surgery may be necessary. Females with PJS need to have annual gynecologic examinations by age 18, and breast mammography starting between the ages of 25 and 35. Males with PJS need to have annual testicular examinations. If a person with PJS develops cancer, it is treated as it would be in the general population.
See Also Cancer genetics; Familial cancer syndromes
Resources
PERIODICALS
McGarrity, T., et al. "Peutz-Jeghers Syndrome." The American Journal of Gastroenterology 95 (2000): 596-604.
Wang, J., et al. "Germline Mutations of the LKB1 (STK11) Gene in Peutz-Jeghers Patients." Journal of Medical Genetics 36 (1999): 365-8.
Westerman, A.M., and J.H.P. Wilson. "Peutz-Jeghers Syn drome: Risks of a Hereditary Condition." Scandanavian Journal of Gastroenterology 34 Suppl 230 (1999): 64-70.
ORGANIZATIONS
Genetic Alliance. 4301 Connecticut Ave. NW, Suite 404, Wash ington, DC, 20008-2304. (202) 966-5557. <http://www.geneticalliance.org>. Support, education, and advocacy.
Network for Peutz-Jeghers Syndrome and Juvenile Polyposis Syndrome. <http://www.epigenetic.org/~pjs/homepage.html>. Online support group, list of physicians interested in PJS, research studies, and a mutation database.
Laura L. Stein, M.S., C.G.C.
KEY TERMS
Gynecomastia
—Overdevelopment of the mammary glands in males; male breast development.
Intussusception
— The folding of one segment of the intestine into another segment of the intestine.
Pathognomonic
—Characteristic of a disease; a pattern of symptoms not found in any other condition.
Polyp
—A mushroom-like growth that may be a precursor to cancer.