PtenTurkiye.org' is a national ( Turkish), web-based registry for PTEN Hamartoma Tumour ( PHTS) syndrome established in 2022. It is designed to increase awareness, gather scientific knowledge by collaboration and increase data accessibility, collect high-quality data on the epidemiology, genetic background and natural history of PHTS especially for pediatric patients so that more accurate follow up guidelines can be recommended.

There is a limited understanding of the natural history of childhood-onset PTEN Hamartoma Tumour Syndrome (PHTS) as a cancer predisposition syndrome. Patient registries are important for longitudinal follow up of these patients. Our aim is to create a Turkish registry especially for pediatric PHTS patients, but registry is open to adult PHTS patients as well.

The purpose is to engage families with children with PHTS in the data-sharing process to accelerate research and drug development and share their experiences with other families as a support if they agree to do so. The registry is open to both adults and children with PHTS.

Most pediatric patients with PHTS have autism spectrum disorders, developmental delays and/or intellectual deficiencies. Patient registry will help us see if they are getting appropriate behaviour interventions. There is no consensus on the guidelines for cancer surveillance in children. The investigators will follow these patients according to 'pediatric follow-up protocol for PTEN (Phosphatase and tensin homolog) mutated children' created by Ciaccio et al. Patient registry will also help if these guidelines are sufficient or need improvements.

Once the individual or their parent/guardian has consented to participate in the registry, the researchers will collect their past and current medical, familial, and other necessary demographic information from their medical records and face to face interviews. The investigators will follow up patients every 6 months or earlier if needed. The investigators will do thorough physical and dysmorphological exam (using autism research exchange dysmorphology check list). For patients with autism and other behavioral problems, the investigators will refer them to child and adolescent psychiatry clinics for evaluation.

Inclusion Criteria:

• Patients who have clinical findings of PHTS and have mutation in PTEN gene ( VUS included if show clinical findings) and agree to participate in the study

Exclusion Criteria:

• Patients who do not have clinical findings of PHTS and do not have mutation in PTEN gene and do not agree to participate in the study

Patients living in Türkiye from age 1 to onwards with both genetic and clinical diagnosis of PTEN Hamartoma Tumor syndrome

Results of the data

After the results is published

Researchers need to directly contact the principal investigator to discuss this