FaCD Online Syndrome Fact Sheet

Last updated: 23 Jun 2008

Name: Porokeratosis

Synonym: incl.: Porokeratosis of Mibelli, Disseminated Superficial Actinic Porokertosis, Porokeratosis Palmaris Plantaris et Disseminata, Porokeratosis Punctata Palmaris et Plantaris, Linear Porokeratosis

Mode of Inheritance: AD/ de novo?

Genes

DSAP2, mapped to 15q25.1-q26.1
SART3, mapped to 12q24.1

Tumor features

skin cancer, basal cell
skin cancer, squamous cell

Non-tumor features

hyperkeratotic skin patches with central atrophy (crater-like)

Comment

This group of disorders is characterized by the occurrence of oval/circular hyperkeratotic skin patches with some central atrophy, resulting in a crater-like appearance. Several types have been reported: placque-type porokeratosis of Mibelli (PM), disseminated actinic superficial porokeratosis (DSAP), porokeratosis palmaris, plantaris et disseminata (PPPD), porokeratosis punctata palmaris et plantaris (PPPP) and linear porokeratosis (part of DSAP?)[1;2]. Porokeratosis is associated with an increased risk to develop squamous cell skin cancer and to a lesser degree basal cell cancer, with the strongest association reported for linear porokeratosis (19 % of cases developed skin cancer), followed by PPPD (9.5%), PM (7.6%) and DSAP (3.4%); unknown % in PPPP [1-11]. The disorders are regarded as an autosomal dominant condition with reduced penetrance and a predilection for males.

References

[1] Schamroth JM, Zlotogorski A, Gilead L. Porokeratosis of Mibelli. Overview and review of the literature. Acta Derm Venereol 1997; 77(3):207-213.
[2] Happle R. Cancer proneness of linear porokeratosis may be explained by allelic loss. Dermatology 1997; 195(1):20-25.
[3] James WD, Rodman OG. Squamous cell carcinoma arising in porokeratosis of mibelli. Int J Dermatol 1986; 25(6):389-391.
[4] Lozinski AZ, Fisher BK, Walter JB, Fitzpatrick PJ. Metastatic squamous cell carcinoma in linear porokeratosis of Mibelli. J Am Acad Dermatol 1987; 16(2 Pt 2):448-451.
[5] Sehgal VN, Dube B. Porokeratosis (Mibelli) in a family. Dermatologica 1967; 134(4):219-224.
[6] Larregue M, Prigent F, Lorette G, Canuel C, Titi M, Champion R, Alcalay D. [Porokeratosis of Mibelli in two monozygotic twins (author's transl)]. Ann Dermatol Venereol 1981; 108(2):151-156.
[7] Yedomon HG, Do Ango Padonou F. [Mibelli porokeratosis in 2 brothers]. Ann Dermatol Venereol 1996; 123(3):171-173.
[8] Sengupta S, Das JK, Gangopadhyay A. Multicentric squamous cell carcinoma over lesions of porokeratosis palmaris et plantaris disseminata and giant porokeratosis. Indian journal of dermatology, venereology and leprology 2005 Nov-Dec; 71(6):414-6.
[9] Maubec E, Duvillard P, Margulis A, Bachollet B, Degois G, Avril MF. Common skin cancers in porokeratosis. The British journal of dermatology 2005; 152(6):1389-91.
[10] Guenova E, Hoetzenecker W, Metzler G, Röcken M, Schaller M. Multicentric Bowen disease in linear porokeratosis. European journal of dermatology : EJD 2007 Sep-Oct; 17(5):439-40.
[11] Curnow P, Foley P, Baker C. Multiple squamous cell carcinomas complicating linear porokeratosis. The Australasian journal of dermatology 2003; 44(2):136-9.