Symptoms and characteristics of PHTS

Having an alteration in the PTEN gene can have many and varied consequences. This, as well as other factors such as age and sex, means that different people with PHTS have varied symptoms, appearing at different times in their lives.

The underlying reasons for these differences are not well understood and are an important area of research that PTEN Research is supporting.

The more common symptoms and characteristics seen in children and adults with PHTS are shown in the table.  Importantly, not all people with PHTS will have all these symptoms.





  • Up to 85% chance that people with PHTS may develop cancer at some time in their life, usually as an adult.
  • However, the risk varies significantly by both cancer type and sex. 
  • Particularly breast, thyroid, kidney and endometrial cancers.

Non-cancerous lumps


  • Called hamartomas.
  • Most common in the skin, gums, tongue, breasts and thyroid gland.

Enlarged head


  • Called macrocephaly.
  • Caused by overgrowth of brain tissue.

Developmental disorders


  • Called neurodevelopmental delay.
  • Milestones for speech, sitting and walking may be later than usual, IQ may be lower than normal, resulting in long term cognitive difficulties.
  • Some people have autism spectrum disorder.

Blood vessel abnormalities and growths

  • Called vascular anomalies.

Gastro-intestinal growths

  • Called polyposis.
  • A specific type of non-malignant growth that can develop in the lower part of intestines.