Bannayan-Riley-Ruvalcaba syndrome

Bannayan-Zonana syndrome 1

Bannayan-Riley-Ruvalcaba syndrome (also known as Bannayan-Zonana syndrome or Riley-Smith syndrome) is a genodermatosis associated with a mutation in the PTEN gene. It is characterized by a triad of symptoms including macrocephaly, genital lentigines, and intestinal polyposis. ICD-10 code is Q87.8.

The syndrome occurs in males, with isolated cases reported in females. The prevalence is unknown. It is an autosomal dominant disorder associated with a mutation in the PTEN tumor suppressor gene encoding a tyrosine phosphatase located on chromosome 10q23.3. Sporadic cases have been reported. Some authors also include PTEN hamartoma tumor syndrome, which includes Bannayan-Riley-Ruvalcaba syndrome, Cowden syndrome, and Proteus syndrome.

The symptoms of the disease, unlike Cowden syndrome, manifest from birth or early childhood.

Dermatological symptoms:

  • Genital lentigines (85% of cases in males) - brown spots in the genital area, scrotum, and vulva, often isolated from each other.
  • Multiple lipomas (75% of cases)
  • Hemangiomas (40% of cases)
  • Lymphangiomas (10% of cases)
  • Warty and acanthotic lesions on the face and neck (up to 10% of cases)
  • Multiple acrochordons in the neck, axillary folds, and groin creases (up to 10% of cases)

Non-cutaneous symptoms:

  • Macrocephaly
  • High birth weight and size
  • Developmental disorders or delays, particularly in speech and motor skills
  • Proximal myopathy in 2/3 of cases
  • Hypotonia
  • Scoliosis
  • Funnel chest
  • Intestinal obstruction
  • Hashimoto thyroiditis
  • Hematochezia (blood in the stool)

Endoscopic examination and biopsy reveal hamartomatous intestinal polyps in 45% of cases. There is an increased risk of malignant tumors (thyroid, breast, kidney). Thyroid cancer has been reported at the age of 6.

Diagnosis is based on family history, clinical data, endoscopy (gastrofibroscopy and colonoscopy), and genetic testing for the PTEN gene, which detects mutations in 60-70% of cases. Fecal occult blood testing, blood tests for anemia, thyroid and breast ultrasound (up to 18 years of age), and renal tomography are recommended.

  • Peutz-Jeghers syndrome
  • Infantile hemangioma
  • Familial lipomatosis
  • Cowden syndrome
  • Acanthosis nigricans
  • Neurofibromatosis type 1
  • Melanoma
  • Lentigo
  • CafĂ©-au-lait spots
  • Penile melanosis
  • Melanocytic nevus

No specific treatment is available. Clinical and laboratory monitoring is recommended. In cases of skin lesions, lipomas, hemangiomas, lymphangiomas, and acrochordons may be excised, and laser therapy may be used for pigmented lesions.