National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Linear porokeratosis


Other Names:
Congenital facial linear porokeratosis (type)
Linear porokeratosis is a rare skin condition characterized by streaks of reddish-brown patches surrounded by a ridge-like border.[1] The patches usually develop in infants or young children, but they sometimes develop in adults.[2] Patches may be on one area of the body (localized) or on multiple areas (generalized). They usually develop in a pattern over the skin known as the "lines of Blaschko," and most commonly occur on the arms or trunk.[2][1] Some people experience itching or pain where the patches occur.[2]

Linear porokeratosis is thought be a form of disseminated superficial actinic porokeratosis (DSAP). Researchers think that people with linear porokeratosis may have one inherited mutation in a gene that causes DSAP.[3] It is thought that a second mutation in that gene is acquired (a somatic mutation), occurring in only some cell lines. This may cause the presence of streaks of patches, rather than more widespread patches.[3][1][2]

Treatment options depend on each person's symptoms. There are no specific recommendations for treatment because no randomized clinical trials have been done. Options may include topical therapies, oral retinoids, cryotherapy, electrodessication, and surgery.[2] Linear porokeratosis can progress to skin cancer (squamous cell and basal cell carcinoma), so sun protection and watching for changes within patches are recommended.[1][2]
Last updated: 11/21/2017
There are no established treatment recommendations for any form of porokeratosis because no randomized clinical trials have been done. Treatment options depend on each person's symptoms and concerns. Responses to treatment are unpredictable, so a person may have to try more than one treatment, or a combination of treatments.[2] Options for treatment of porokeratosis may include:[2][1]
Linear porokeratosis can progress to skin cancer (squamous cell and basal cell carcinoma). If the purpose of treatment is to prevent its progression to cancer, surgical removal is typically recommended. Sun protection is also important to decrease the risk for cancer. Watching for changes within patches may help to detect cancer earlier.[1][2]
Last updated: 11/21/2017

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Linear porokeratosis. Click on the link to view a sample search on this topic.

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  • My daughter has linear porakeratosis and is going to have photodynamic light therapy.  She had scalded skin syndrome when she was a baby: will she still be able to recieve the treatment and will she need pain relief? See answer


  1. Prak AH. Porokeratosis. Medscape Reference. August 7, 2017; https://emedicine.medscape.com/article/1059123-overview.
  2. Spencer LV. Porokeratosis. UpToDate. Waltham, MA: UpToDate; September 1, 2016; https://www.uptodate.com/contents/porokeratosis.
  3. Sommerlad M, Lock A, Moir G, McGregor J, Bull R, Cerio R, Harwood C. Linear porokeratosis with multiple squamous cell carcinomas successfully treated by electrochemotherapy. Br J Dermatol. December, 2016; 175(6):1342-1345. https://www.ncbi.nlm.nih.gov/pubmed/27086492.