StudyRareStudyRare
Log in to add personal notes on this page.

A patient with a spontaneous pneumothorax has numerous skin-colored papules on the face and neck (fibrofolliculomas). Imaging reveals bilateral renal tumors.

AD; FLCN (folliculin)

  • Fibrofolliculomas (skin lesions - face, neck)
  • Pulmonary cysts → spontaneous pneumothorax
  • Renal tumors (chromophobe RCC, oncocytoma, hybrid)
  • Bilateral/multifocal renal tumors
  • Clinical suspicion from the dermatologic-pulmonary-renal triad: multiple fibrofolliculomas, basally located lung cysts with spontaneous pneumothorax, and bilateral/multifocal renal tumors
  • Renal tumors are characteristically chromophobe RCC, oncocytoma, or hybrid oncocytic/chromophobe tumors
  • Confirm with germline FLCN sequencing and deletion/duplication analysis
  • Renal surveillance with periodic abdominal MRI (preferred over CT to limit cumulative radiation); nephron-sparing surgery for tumors reaching ~3 cm
  • Counsel on pneumothorax risk: smoking cessation, caution with high-pressure activities (scuba diving), and prompt evaluation of acute dyspnea or chest pain
  • Dermatologic management of symptomatic fibrofolliculomas (benign; treated for cosmesis)
  • Cascade testing of at-risk relatives

"Bird-Hawk-Dube" syndrome, mutation in FaLCoN: Birds fly in the air, which reminds you of lung cysts and pneumothorax.

BiRRT = Bilateral Renal and Respiratory (Lung) Tumors and cysts. HOG = Hair follicle OverGrowth with fibrous tissue (fibrofolliculomas). DUBe = Dermatologic features are Usually Benign.

This table compares genetic disorders presenting with facial papules, including BHD, NF1, Cowden, TSC, nevoid basal cell carcinoma, and CYLD cutaneous syndrome.

Genetic disorders with facial papules: FLCN (BHD/fibrofolliculomas), NF1 (neurofibromas), PTEN (Cowden/trichilemmomas), TSC1/TSC2 (angiofibromas), PTCH1 (basal cell nevi), CYLD (trichoepitheliomas)
Genetic disorders with facial papules: FLCN (BHD/fibrofolliculomas), NF1 (neurofibromas), PTEN (Cowden/trichilemmomas), TSC1/TSC2 (angiofibromas), PTCH1 (basal cell nevi), CYLD (trichoepitheliomas)

Reference Links