Peutz–Jeghers syndrome

• Peutz–Jeghers syndrome is also known as hereditary intestinal polyposis syndrome.
• An autosomal dominant genetic disease characterized by the development of benign hamartomatous polyps in the GIT and hyperpigmented macules on the lips and oral mucosa.
• Prevalence of approximately 1 in 100,000 to 200,000 births.
  

Diagnosis

Need 2 of 3 of:

• Family history
• Mucocutaneous lesions causing patches of hyperpigmentation in the mouth and on the hands and feet.
  
  • Oral pigmentations are the first to appear and play an important part in early diagnosis. Intraorally, they are most frequently seen on the gingiva, hard palate and inside of the cheek. The mucosa of the lower lip is almost invariably involved as well.
• Hamartomatous polyps in the gastrointestinal tract. These are benign polyps with an extraordinarily low potential for malignancy.
• Mutation in the tumour supressor gene STK11 on chromosome 19.

Natural history

• Most patients will develop melanotic macules during the first year of life.
• Intussusception usually first occurs between the ages of six and 18 years old.
  
• Most people will have developed some form of neoplastic disease by age 60.
• Cumulative lifetime cancer risk begins to rise in middle age.
• Cumulative risks by age 70 for all cancers, gastrointestinal (GI) cancers, and pancreatic cancer are 85%, 57%, and 11%, respectively.

References

• http://en.wikipedia.org/wiki/Peutz-Jeghers_syndrome
• http://www.answers.com/topic/peutz-jeghers-syndrome