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PTEN Sequencing and Deletion/Duplication

Test code(s) 92566

This test is used to identify individuals with autosomal dominant PTEN hamartoma tumor syndrome (PHTS), which includes Cowden syndrome. This test detects single-nucleotide variants, deletions, and duplications in the PTEN gene, which encodes the tumor suppressor protein phosphatase and tensin homolog. Sample reports and information regarding the specific variants analyzed for each gene are available on our website

If a familial mutation has been detected by sequencing or deletion/duplication studies, the Hereditary Cancer Single Site(s) test (test code 93945) may be considered. Official test results of the family member must be available for laboratory review. For more information, please visit our website To discuss a family history with a Quest Diagnostics genetic counselor, please call Quest Genomics Client Services at 1.866.GENE.INFO (1.866.436.3463).

Generally, this test may be appropriate for individuals with one or more of the following1:

Major features

  • Breast cancer
  • Endometrial cancer
  • Follicular thyroid cancer
  • Multiple gastrointestinal hamartomas or ganglioneuromas
  • Lhermitte-Duclos disease
  • Macrocephaly
  • Macular pigmentation of the glans penis
  • Mucocutaneous lesions such as trichilemmomas, palmoplantar keratosis, oral mucosal papillomatosis, or cutaneous facial papules

Minor features

  • Autism spectrum disorder
  • Colon cancer
  • Three or more esophageal glycogenic acanthoses
  • Lipomas
  • Intellectual disability
  • Papillary or follicular variant of papillary thyroid cancer
  • Thyroid structural lesions such as adenoma, nodules, or goiter
  • Renal cell carcinoma
  • Single gastrointestinal hamartoma or ganglioneuroma
  • Testicular lipomatosis
  • Vascular anomalies

Informed consent following genetic counseling is strongly recommended.

For more information or to discuss a family history with a Quest genetic counselor, please call
Quest Genomics Client Services at 1.866.GENE.INFO (1.866.436.3463).

The right time is different for every individual. An individual’s current medical status, personal experience with features of PHTS, treatment or screening plan, and general readiness for genetic information all influence the decision to be tested. Having an open dialogue with individuals about these topics can assist with shared decision-making.

Upon receipt of a fully completed order, our team will verify coverage with your patient’s healthcare insurance plan and estimate their likely out-of-pocket responsibility. If your patient’s estimated responsibility is over $100, we will notify you and/or your patient prior to test initiation to discuss options for continuation or cancellation of the test. Please note that orders lacking complete information will not be processed.

On average, results will be completed 14 to 21 days after receipt of the sample in the laboratory if the family history form and order are complete and the health plan does not require preauthorization. Turnaround time may vary based on delays caused by incomplete orders or insurance authorizations.

Individuals with a positive result have a pathogenic or likely pathogenic variant detected in the PTEN gene and a diagnosis of autosomal dominant PHTS.1 A positive result does not mean that an individual has a diagnosis of cancer or will develop all the features of PHTS. Specific risk information will be provided in the result report, and you can visit our website at for more information.

The National Comprehensive Cancer Network (NCCN®) provides up-to-date surveillance and management recommendations for individuals with a positive result.1

A negative result means that a pathogenic or likely pathogenic variant was not detected in the PTEN gene. For more information regarding specific genetic variants analyzed in this assay, please refer to the methods and limitations section of the genetic testing report. Clinical diagnostic criteria are available if an individual is still suspected of having a diagnosis of PHTS in the context of a negative genetic testing result.2

A VUS result means that the variant has not been previously described in the literature or that the clinical significance is unclear based upon currently available evidence. Medical management decisions should be based on personal and family history. Family studies may help to learn more about the clinical significance of this variant. The classification and interpretation of the variant(s) identified reflect the current state of Quest’s understanding at the time of the report. Variant classification and interpretation are subject to professional judgment and may change for a variety of reasons including, but not limited to, updates in classification guidelines and availability of additional scientific and clinical information. It is important to check in with the laboratory annually for variant updates because new information regarding the variant and classification may become available over time. Please visit for information about variant classification. If you have questions, please call Quest Genomics Client Services at 1.866.GENE.INFO (1.866.436.3463) to speak with a genetic counselor.


  1. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®). Genetic/familial high-risk assessment: breast, ovarian, and pancreatic. Version 1.2020.Published December 4, 2019.
  2. Pilarski R, Burt R, Kohlman W, et al. Cowden syndrome and the PTEN hamartoma tumor syndrome: systematic review and revised diagnostic criteria. J Natl Cancer Inst. 2013;105(21):1607‐1616. doi:10.1093/jnci/djt277


This FAQ is provided for informational purposes only and is not intended as medical advice. A clinician’s test selection and interpretation, diagnosis, and patient management decisions should be based on his/her education, clinical expertise, and assessment of the patient.

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