Porokeratosis: An enigma beginning to unravel.

Porokeratosis is a keratinization disorder with unclear etiopathogenesis, varied clinical presentation and characteristic histopathology, and is usually unresponsive to current therapeutic options. Until now, it was considered to be a clonal disorder with immunity, ultra violet radiation and other factors playing important roles in etiopathogenesis. It is now known that abnormalities in the mevalonate pathway are responsible for this clonal keratinization abnormality. New variants of porokeratosis like eruptive bullous, pruriginous, lichen planus like, follicular variants and porokeratoma have been described. While the cornoid lamella is the classical histopathologic feature, dermoscopy and reflectance confocal microscopy make the diagnosis clearer. Development of malignancy in a few variants is a concern. Linear, disseminated superficial actinic and giant lesions are most prone to developing malignancies. Bowen's disease, squamous cell carcinoma, basal cell carcinoma and even melanoma have been reported in cases of long-standing porokeratosis. Newer modalities of therapy such as photodynamic therapy, ingenol mebutate and HMGCoA inhibitors may play a role in the future.

[CME Dermatology 24/Answers: Porokeratosis]. / CME-Dermatologie 24/ Antworten: Porokeratose.

CME Dermatology 24/Answers: Porokeratosis Abstract. Porokeratoses are a heterogeneous group of cornification disorders with the characteristic histological feature of the cornoid lamellae in the area of the marginal ridge. It is a rare but characteristic disease that occurs primarily in adulthood. Men are slightly more likely to be affected. The etiopathogenesis that leads to the transformation of the keratinocytes remains unclear; associations with genetic mutations and trigger factors such as UV rays and immunosuppression were observed. Due to the risk of malignant degeneration, consistent sun protection and regular clinical controls should take place. Cryotherapy, ablative laser therapy, curettage, photodynamic therapy or topical application of fluorouracil (5-FU), imiquimod and retinoids can be used to treat itchy, painful or cosmetically disturbing porokeratoses, depending on the location and severity.

[CME Dermatology 24: Porokeratosis]. / CME-Dermatologie 24: Porokeratose CME-Fragen.

CME Dermatology 24: Porokeratosis Abstract. Porokeratoses are a heterogeneous group of cornification disorders with the characteristic histological feature of the cornoid lamellae in the area of the marginal ridge. It is a rare but characteristic disease that occurs primarily in adulthood. Men are slightly more likely to be affected. The etiopathogenesis that leads to the transformation of the keratinocytes remains unclear; associations with genetic mutations and trigger factors such as UV rays and immunosuppression were observed. Due to the risk of malignant degeneration, consistent sun protection and regular clinical controls should take place. Cryotherapy, ablative laser therapy, curettage, photodynamic therapy or topical application of fluorouracil (5-FU), imiquimod and retinoids can be used to treat itchy, painful or cosmetically disturbing porokeratoses, depending on the location and severity.

Cluster of Vacuolated Spinous Keratinocytes: A Clue to Cornoid Lamellation and a Case of Porokeratosis Disseminata.

Cornoid lamella is a definitive diagnostic feature of porokeratosis, a disorder of keratinization that has various different clinical presentations. A tiered column of parakeratosis and a diminished granular layer with dyskeratotic keratinocytes at the column base are all useful and known features of cornoid lamellation. We have found a cluster of vacuolated spinous cells to be a reliable fourth feature of cornoid lamellation and a feature when present alone to be a reliable sign of impending cornoid lamellation on deeper sections. Furthermore, we present a novel clinical phenotype of disseminated papular porokeratosis with effective clinical response to combination of phototherapy, oral and topical retinoids, and topical vitamin D derivative, which too contained all 4 features of cornoid lamellation.

Effective treatment of disseminated superficial actinic porokeratosis with chemical peels - customary treatment for a rare disease.

Background: Disseminated superficial actinic porokeratosis (DSAP) is a rare dermatologic disorder of the epidermis. Often misdiagnosed as chronic UV-damage or actinic keratoses, patients are treated for years with different therapeutic options with little success. Current treatment options include imiquimod, ingenol mebutate, cryosurgery, photodynamic therapy and topical or systemic therapy with retinoids. Since those approaches show only little success or come along with major side effects, therapeutic alternatives are strongly requested. Methods: We report a series of five female patients with history of DSAP that were successfully treated with chemical peels. Results: All patients suffered from the disease for 14.4 years on average and all were refractory to at least two therapeutic options, mostly imiquimod and topical tretinoin. Patients were treated with glycolic acid 50% and salicylic acid 25% in a two-layer-technique. After a mean of three cycles every 6 weeks a clear reduction in lesion was assessed by physicians. Patients were highly satisfied with outcome and rare occurrence of side effects as assessed by TSQM questionnaire. Conclusion: Chemical peels are safe and well tolerated treatment options for patients with refractory porokeratosis. As characteristic for chronic diseases, frequent repetition of treatment is needed in order to control disease activity.

Linear porokeratosis associated with Bardet-Biedl syndrome: A case report.

This case report presents a 17-year-old boy with Bardet-Biedl syndrome (BBS) and a long-standing hyperpigmented eruption on the left trunk and upper extremity, clinically and histologically consistent with linear porokeratosis (LP). BBS patients frequently require solid organ transplant, and subsequent immunosuppression places them at especially high risk for malignant transformation of premalignant skin lesions such as LP. Although BBS affects multiple organ systems, there are only a handful of case reports detailing associated cutaneous involvement, and, to our knowledge, this is the first reported case of linear porokeratosis occurring in patient with BBS.

Poroqueratosis de Mibelli. Presentación de caso / Mibelli's porokeratosis. Presentation of case

RESUMEN Se realizó la presentación de dos pacientes con poroqueratosis de Mibelli por ser una dermatosis poco frecuente, por lo que debe ser de interés para los profesionales de diferentes disciplinas, bien por relacionarse con el cáncer de piel o con disímiles enfermedades. Los pacientes estudiados fueron: paciente femenino de 62 años de edad, piel blanca y ocupación ama de casa. Fue remitida por presentar piel con fototipo cutáneo II, una lesión en placa de color amarillento, bordes elevados, hiperqueratósicos, centro atrófico de 1 cm de diámetro; localizada en cara ántero-externa de pierna derecha. El otro paciente, de 59 años, sexo masculino, piel blanca, y ocupación pescador. Solicitó los servicios por presentar piel fototipo cutáneo II lesión en placa de color amarillento, bordes elevados, hiperqueratósicos, centro atrófico de 2cm de diámetro, localizada en cara póstero-externa de antebrazo derecho. Se les realizó biopsia de ambas lesiones. El diagnóstico fue la poroqueratosis de Mibelli para la prevención del cáncer de piel. Ambos pacientes presentaron en común fototipo cutáneo II y otras manifestaciones cutáneas inducidas por la exposición solar. La terapéutica utilizada fue la extirpación quirúrgica, que resultó también el proceder diagnóstico Se orientaron medidas para la prevención del cáncer de piel con bloqueadores solares, y protegerse de los rayos solares con ropa adecuaday otros accesorios (AU).

ABSTRACT Two patients with Mibelli´s porokeratosis were presented because it is a few frequent dermatosis that might be of interest for professionals of different disciplines since it is related to skin cancer and to several other diseases. The first studied patients was 62 years old, female, white, and a housewife, remitted due to presenting skin with cutaneous phototype II, a yellowish lesion in plaque, risen, hyperkeratoid borders and atrophic center of 1 cm diameter, located in the anterior-external face of the right leg. The other patient was 59 years old, male, white, and a fisherman. He assisted the service presenting skin with cutaneous phototype II, a yellowish lesion in plaque, risen, hyperkeratoid borders and atrophic center of 2 cm diameter, located in the posterior-external face of the right forearm. A biopsy of both lesions was carried out. The diagnosis was Mibelli´s porokeratosis. Both patients presented a common cutaneous phototype II and skin manifestations induced by the sun exposition. The used therapeutic was the surgical removal, that also was the diagnosis procedure. Preventing skin cancer with sun blockers was oriented and also wearing adequate clothes and other accessories (AU).

Linear porokeratosis associated with multiple squamous cell carcinomas.

Linear porokeratosis is a rare subtype of porokeratosis with a higher rate of malignant transformation than other subtypes of porokeratosis. Identification of cornoid lamellae on histology allows for definitive diagnosis, which makes high clinical suspicion and appropriate biopsy essential in establishing the correct diagnosis and developing an effective management plan. We present a case report of linear porokeratosis and discuss aspects of etiology, diagnosis, and management.

Treatment of Porokeratosis: A Systematic Review.

BACKGROUND: Porokeratosis (PK) is a rare skin disease of unknown etiology. It consists of a keratinization disorder, which may appear in several clinical forms and can undergo malignant transformation. The histopathological hallmark of PK is the cornoid lamella. While many topical, systemic, and surgical treatment modalities for PK have been described, no randomized controlled trials have been performed yet. Because of a lack of treatment standards for PK, European and international guidelines cannot be created. OBJECTIVE: The aim of this systematic review is to outline options for treating PK. METHODS: We performed a systematic literature search in an electronic database for published literature. A total of 88 articles fulfilling our inclusion criteria were found. RESULTS: There were no randomized controlled trials on the treatment of PK, but mainly case reports and case series. Porokeratosis of Mibelli showed the best outcomes after treatment with imiquimod cream and linear PK responded well to topical or systemic retinoids. Topical vitamin D acid derivatives may be the best therapeutic option for disseminated PK. Surgical interventions and cryotherapy may be preferred in areas where the use of topical agents is difficult or contraindicated. CONCLUSION: To offer patients with PK an evidence-based high-quality standardized therapy, randomized controlled trials are needed.

Poroqueratosis genital: reporte de caso y revisi¢n de la literatura / Genital porokeratosis: case report and review of the literature

La poroqueratosis es un grupo de dermatosis raras que se producen debido a un trastorno del proceso de queratinizaci¢n. Hay diferentes formas cl¡nicas, pero caracter¡sticamente se presenta como p pulas delimitadas con centro ligeramente atr¢fico y borde elevado hiperquerat¢sico, pueden causar prurito. En la histopatolog¡a se puede observar las lamelas carnoides y la hipogranulosis como caracter¡sticas importantes. Se presenta el caso de un paciente var¢n de 32 a¤os de edad con lesiones en la regi¢n genital una localizaci¢n rara para esta enfermedad pero con cl¡nica e histopatolog¡a t¡picas, que fue tratado con crioterapia.

The porokeratosis is a rare dermatosis occurring due to a disorder of keratinization process. There are different clinical forms, but characteristically arises as papules delimited with center slightly atrophic and edge high hyperkeratotic, which can cause itching. The histopathology, you can see the lamellae carnoides and the hipogranulosis as important features. A case of a 32-year-old male patient is presented with lesions in the genital region, a rare location for this disease but with typical clinical and histopathology, which was treated with cryotherapy.

Porokeratoses: an update of clinical, aetiopathogenic and therapeutic features.

Porokeratoses represent a group of uncommon, acquired or hereditary dermatoses, due to a keratinization disorder whose origin is still unclear; they could be due to the expansion of a clone of abnormal epidermal keratinocytes. Several clinical forms exist, of which the most common is disseminated superficial actinic porokeratosis; other forms include Mibelli, disseminated superficial, linear, palmoplantaris punctata and palmaris, plantaris et disseminata. These may coexist in the same patient or in different members of the same family. Porokeratoses manifest clinically with annular or linear, well-circumscribed keratotic plaques and share a common histological hallmark, the cornoid lamella, a vertical stack of parakeratotic corneocytes within the horny layer resting on a shallow depression of the underlying epidermis. Porokeratoses may be seen in the setting of various immunodeficiencies, namely in organ-transplant recipients, in whom the course of the disease may parallel the degree of immunosuppression. The overall prognosis of porokeratoses is favourable but is shadowed by the possibility of malignant transformation of the lesions (usually into squamous cell carcinoma); this happens in less than 10% of cases but may prove fatal. Although several surgical or medical (local or systemic) treatments have been tried, none of them has shown consistent and long-term efficacy.

Case for diagnosis.

Porokeratosis is a primary keratinizing disorder of unknown etiology. This disorder is characterized by the presence of centrifugally enlarging hyperkeratotic plaques, associated with the histopathological hallmark of cornoid lamellae. Genital porokeratosis is extremely rare. No more than thirty cases have been reported in the literature, including only one case of linear porokeratosis confined to the genital area. This case report describes a patient with genital linear porokeratosis, who was successfully treated with cryotherapy. Over two years of follow-up, the lesion improved and there was no evidence of recurrence or signs of malignant transformation. Nevertheless, there is a need for long-term follow-up data on recurrence and malignant transformation.