Spring 2003

Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome (PJS) is a rare hereditary condition that affects 1 in 160,000 to 1 in 280,000 people. People with PJS develop polyps in their gastrointestinal tract. The particular type of polyp seen is called a “hamartoma”. The most common areas to develop hamartomas are the duodenum (first part of the small intestine), colon and stomach (see Figure 1). Often, people with PJS are first recognized because they experience intussusception, which is a blockage of the intestine requiring prompt medical attention. Most people with PJS also have a distinct freckling pattern called melanin pigmentation (see Figure 2). The spots tend to be present in early childhood, but often fade with age, and are usually located on the lips, inner cheeks, eyelids, hands or feet.

The Genetics of PJS

PJS is genetic and can be passed from parent to child. Recently, one of the genes responsible for this syndrome was identified. The gene is called STK11; it has also been referred to as LKB1. Because of this discovery, genetic testing is now available for certain families. Genetic testing involves a blood test, and it is usually recommended that a family member with PJS be tested first. This is to determine if the specific mutation causing PJS in a particular family can be found. If an affected person tests positive for a mutation, other at-risk family members can then be tested. Currently, the cost of testing for the first person in the family is approximately $1500. It is unknown if insurance will cover the cost. A genetic counselor can help interested persons to learn more about genetic testing.

Screening Recommendations

A study by Giardiello et al. in 2000 had some surprising, and concerning, conclusions. Dr. Giardiello and his colleagues reviewed published material pertaining to PJS in an attempt to determine the lifetime risk of various cancers in individuals affected with this condition. It was determined that the overall lifetime risk to develop at least one type of cancer was 93%. The most commonly seen cancers were those of the breast, colon, pancreas and stomach. Increased risk was also seen for cancers of the small intestine, lung, ovary, cervix, uterus and testes. As a result, screening recommendations for people with PJS are as follows:

Beginning at age 12 years, affected individuals should have a history and physical exam every year with routine blood tests. They should also undergo upper endoscopy, colonoscopy, and small bowel series every 2 years. In addition, males should be examined for testicular tumors.

At age 18 years, affected females should begin having a gynecological examination with clinical breast examination, transvaginal ultrasound and CA-125 every year.

At age 25 years, females should begin yearly mammography. Males and females should have a CT scan every 1 to 2 years OR endoscopic ultrasound and CA 19-9 every 1 to 2 years.

Dr. Giardiello’s study estimated the lifetime risk of pancreas cancer to be 36%. Therefore, screening for this particular organ is recommended. However, medical scientists have yet to identify a proven method for such surveillance. Dr. Marcia Canto is conducting an ongoing study at The Johns Hopkins Hospital to evaluate the use of endoscopic ultrasound for pancreas cancer screening. The study is open to individuals with a significant family history of pancreas cancer, as well as to individuals with a diagnosis of PJS. The goal is to determine if endoscopic ultrasound is an effective way to detect pancreas cancer at an early stage, or to identify pre-cancerous changes in the pancreas. To learn more about Dr. Canto’s study, and to verify eligibility, interested persons may contact Brenda Ridgeway, the study nurse, at (410) 955-3821.

Information Booklet Available

Finally, the Mid-Atlantic Cancer Genetics Network, in association with the Johns Hopkins Hereditary Colorectal Cancer Registry, is proud to announce the availability of an educational booklet about Peutz-Jeghers syndrome. This patient-friendly publication joins others in the popular series, and is designed to provide individuals with PJS accurate and easy-to-understand information about this rare disorder. To request a copy of the booklet, please contact the colorectal cancer registry coordinator at (410) 955-3875 or toll free at 1-888-77-COLON (772-6566). You may also download the booklet from the Colon Cancer Center website at http://www.hopkins-coloncancer.org .

-Written by Jennifer E. Sollenberger, M.S. Genetic Counselor, Cancer Risk Assessment Program, Johns Hopkins Hospital

Figure 1: Gastrointestinal (GI) Track

ă 1999 Division of Gastroenterology, The Johns Hopkins Hospital

Figure 2: Example of Melanin Spots in PJS