GTR Home > Conditions/Phenotypes > Cowden syndrome

Disease characteristics

Excerpted from the GeneReview: PTEN Hamartoma Tumor Syndrome (PHTS)
The PTEN hamartoma tumor syndrome (PHTS) includes Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome (BRRS), PTEN-related Proteus syndrome (PS), and Proteus-like syndrome. CS is a multiple hamartoma syndrome with a high risk for benign and malignant tumors of the thyroid, breast, and endometrium. Affected individuals usually have macrocephaly, trichilemmomas, and papillomatous papules, and present by the late 20s. The lifetime risk of developing breast cancer is 85%, with an average age of diagnosis between 38 and 46 years. The lifetime risk for thyroid cancer (usually follicular, rarely papillary, but never medullary thyroid cancer) is approximately 35%. The risk for endometrial cancer, although not well defined, may approach 28%. BRRS is a congenital disorder characterized by macrocephaly, intestinal hamartomatous polyposis, lipomas, and pigmented macules of the glans penis. PS is a complex, highly variable disorder involving congenital malformations and hamartomatous overgrowth of multiple tissues, as well as connective tissue nevi, epidermal nevi, and hyperostoses. Proteus-like syndrome is undefined but refers to individuals with significant clinical features of PS who do not meet the diagnostic criteria for PS.

Associated genes

  • Also known as: 10q23del, BZS, CWS1, DEC, GLM2, MHAM, MMAC1, PTEN1, TEP1, PTEN
    Summary: phosphatase and tensin homolog

Clinical features

  • Splenomegaly
  • Abnormality of the pupil
  • Tall stature
  • Heterochromic iris
  • Intestinal polyposis
  • Intellectual disability
  • Kyphosis
  • Anteverted nares
  • Dolichocephaly
  • Cognitive impairment
  • Progressive macrocephaly
  • Irregular hyperpigmentation
  • Incoordination
  • Downslanted palpebral fissures
  • Micrognathia
  • Epibulbar dermoid
  • Seizures
  • Cataract
  • Gynecomastia
  • Retinal detachment
  • Macrocephaly
  • Increased intracranial pressure
  • Hypothyroidism
  • Hydrocele testis
  • Ovarian cyst
  • Polycystic ovaries
  • Abnormality of the tongue
  • Narrow mouth
  • High palate
  • Furrowed tongue
  • Mandibular prognathia
  • Hypoplasia of the maxilla
  • Hearing impairment
  • Myopia
  • Dental malocclusion
  • Pectus excavatum
  • Abnormality of the parathyroid gland
  • Hyperthyroidism
  • Goiter
  • Thyroid adenoma
  • Palmoplantar hyperkeratosis
  • Melanocytic nevus
  • Multiple lipomas
  • Subcutaneous lipoma
  • Angioid streaks of the retina
  • Intellectual disability, mild
  • Communicating hydrocephalus
  • Abnormality of the cardiovascular system
  • Foot polydactyly
  • Nausea and vomiting
  • Migraine
  • Intention tremor
  • Colonic diverticulosis
  • Abnormality of neuronal migration
  • Scoliosis
  • Skeletal dysplasia
  • Genu recurvatum
  • Meningioma
  • Breast carcinoma
  • Neoplasm of the nervous system
  • Hamartomatous polyps
  • Venous insufficiency
  • Transitional cell carcinoma of the bladder
  • Aplasia/Hypoplasia of the cerebellum
  • Shagreen patch
  • Thymus hyperplasia
  • Skin tags
  • Arteriovenous malformation
  • Lower limb asymmetry
  • Thyroiditis
  • Bronchogenic cyst
  • Hyperostosis
  • Exostoses
  • Varicocele
Show all (74)
Go to complete MedGen record for Cowden syndrome

Clinical resources

Practice guidelines

  • ACMG, 2008
    Clinical genetics evaluation in identifying the etiology of autism spectrum disorders
  • NSGC, 2004
    Genetic cancer risk assessment and counseling: recommendations of the national society of genetic counselors.

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