What is Peutz-Jeghers syndrome (PJS)?

Peutz-Jeghers syndrome (PJS) is a condition where people develop characteristic polyps and dark-colored spots and have an increased risk of certain types of cancer.

The gene that is mutated, causing this condition, is responsible for controlling cell growth. People with PJS can develop polyps — called Peutz-Jeghers polyps — in the small bowel, colon, stomach, lungs, nose, bladder and rectum. These polyps are considered hamartomatous polyps. Hamartomatous polyps are benign (not cancerous) overgrowths of tissues.

How is Peutz-Jeghers syndrome (PJS) inherited?

Peutz-Jeghers syndrome (PJS) is an inherited (passed down from a family member) condition. Approximately 50 percent of individuals with PJS have a parent with the syndrome. The other 50 percent of people diagnosed with PJS are the first in the family with the syndrome.

There is a 50 percent chance that a child of someone with PJS might inherit the mutated copy of the gene. There is also a 50 percent chance that the child would not inherit the mutation.

What causes Peutz-Jeghers syndrome (PJS)?

Peutz-Jeghers syndrome (PJS) is caused when a person has a change (mutation) in one copy of the STK11/LKB1 gene. Everyone has two copies of the STK11/LKB1 gene. The copy of the gene with the mutation can be passed on to future generations.

What are the symptoms of Peutz-Jeghers syndrome (PJS)?

Symptoms of Peutz-Jeghers syndrome (PJS) can develop in children and adults. Some symptoms in children may fade away as they age. Symptoms can include:

  • Characteristic dark-colored spots (also called muco-cutaneous pigmentation) on various parts of the body. These spots are typically dark brown or blue in childhood and then fade in the late teenage years. These spots can appear on various parts of the body, including the:
    • Mouth
    • Lips
    • Eyes
    • Nose
    • Hands and feet
    • Anus
  • Development of hamartomatous polyps (non-cancerous overgrowths of tissue)
  • Small bowel obstruction (blockage)
    • Up to 50 percent of patients have experienced a small bowel obstruction requiring surgery before turning 20.
  • Gastrointestinal bleeding
  • Anemia
  • Stomach pain
  • Intussusception of the small bowel (a condition where the small bowel turns itself inside out). This commonly occurs early due to the small bowel trying to pass a large polyp. Patients experience symptoms such as pain, nausea and vomiting, and are typically young. They may be at puberty or in their early teen years.

Last reviewed by a Cleveland Clinic medical professional on 01/02/2019.


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