Linear porokeratosis: treatment with the carbon dioxide laser

Porokeratoses-A Comprehensive Review on the Genetics and Metabolomics, Imaging Methods and Management of Common Clinical Variants

Porokeratosis is a heterogeneous group of keratinising disorders characterised by the presence of particular microscopic structural changes, namely the presence of the cornoid lamella. This structure develops as a consequence of a defective isoprenoid pathway, critical for cholesterol synthesis. Commonly recognised variants include disseminated superficial actinic porokeratosis, disseminated superficial porokeratosis, porokeratosis of Mibelli, palmoplantar porokeratosis (including porokeratosis palmaris et plantaris disseminata and punctate porokeratosis), linear porokeratosis, verrucous porokeratosis (also known as genitogluteal porokeratosis), follicular porokeratosis and porokeratoma. Apart from the clinical presentation and epidemiology of each variant listed, this review aims at providing up-to-date information on the precise genetic background, introduces imaging methods facilitating the diagnosis (conventional and ultraviolet-induced fluorescence dermatoscopy, reflectance confocal microscopy and pathology), discusses their oncogenic potential and reviews the literature data on the efficacy of the treatment used, including the drugs directly targeting the isoprenoid-mevalonate pathway.

[CME Dermatology 24: Porokeratosis]

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.

A case of inflammatory disseminated superficial porokeratosis in a colon cancer patient

Disseminated superficial porokeratosis (DSP) is a specific disorder of keratinization. Genetic studies show that DSP is an autosomal dominant trait. Clinically, the lesions show a sharply demarcated and hyperkeratotic plaque with central atrophy. The lesions appear mainly in the extremities and generally develop with bilateral symmetry. Unusual cases of DSP accompanied by severe pruritus have been reported as "eruptive pruritic papular porokeratosis" or "inflammatory DSP." Histopathologically, inflammatory DSP is characterized by the presence of cornoid lamella with a dense infiltration of eosinophils and lymphocytes in the perivascular area of the upper dermis. Here we report a case of inflammatory DSP in a 84-year-old man with colon cancer who presented with multiple hyperpigmented atrophic macules.

Giant verrucous porokeratosis of Mibelli mimicking psoriasis in a patient with psoriasis

Porokeratosis of Mibelli is a disorder of epidermal keratinization characterized by annular plaques with an atrophic center surrounded by a keratotic wall. We report a case of a giant verrucous porokeratosis of Mibelli mimicking psoriasis that developed in a patient with psoriasis and therefore went unrecognized for a long time. Histologically the lesion combined features of porokeratosis at the periphery and of psoriasis at its center, a picture recently described as "psoriasis encircled by porokeratosis." The possible pathogenetic relationship between psoriasis and the development of porokeratosis is also discussed.

Carbon dioxide laser therapy for an inflammatory linear verrucous epidermal nevus: a case report

The treatment of an inflammatory linear verrucous epidermal nevus (ILVEN), an uncommon type of epidermal nevus, is still controversial. The use of laser therapy is a recently reported method. Although various results have been reported with the use of the laser in the treatment epidermal nevis, the authors have not seen any report on the use of the carbon dioxide laser in ILVEN treatment. They present case of ILVEN treated with the carbon dioxide laser. All symptoms (erythema, excoriation, granulation, and pruritus) disappeared. Instead, a pale pigmentation was seen.

Porokeratosis of Mibelli: Successful treatment with topical 5% imiquimod cream

A 77-year-old woman with a large porokeratosis of Mibelli on the left shin was successfully treated with topical 5% imiquimod cream applied to the entire lesion once daily without occlusion three times a week. A strong inflammatory reaction was achieved in 6 weeks of treatment. The lesion had been present for approximately 6 years and prior treatments included curettage and electrocautery, cryotherapy and topical 5-fluorouracil under occlusion. At the end of treatment with topical 5% imiquimod cream, punch biopsy was negative for porokeratosis. The lesion healed without scarring. At 24-month follow up there had been no sign of clinical recurrence.

Genitoanocrural porokeratosis following chronic exposure to benzene

Porokeratoses are disorders of epidermal keratinization, the aetiology of which remains to be elucidated. We present the uncommon case of a 70-year-old man with genitoanocrural porokeratotic lesions successfully treated by CO2 laser vaporization. The patient's occupational history and the late onset, site and multiplicity of the lesions suggest their induction by benzene, a known carcinogen.

Linear porokeratosis presenting as erosions in the newborn period

The classic appearance of porokeratosis is characterized by a hyperkeratotic annular rim that expands peripherally, leaving an atrophic center. Linear porokeratosis is a variant with collections of such lesions arranged in a linear fashion, usually corresponding to a dermatome or Blaschko's lines. Ulcerations have rarely been reported in patients with porokeratosis. We report an unusual case of linear porokeratosis at birth, with erosions and ulcerations of the face and lower extremity, that eluded diagnosis for nearly a year. Porokeratosis should be considered in the differential diagnosis of erosions in the newborn period.

Genital porokeratosis of Mibelli

Porokeratosis of Mibelli is a disorder of epidermal proliferation in which many different clinical forms can be distinguished. Two male patients with a localized type of porokeratosis limited to the genitalia are reported. Later in life they developed an annular skin lesion with peripheral keratotic ridge. The histological examination of a biopsy specimen showed the characteristic features of porokeratosis. There was no family history of similar skin disorders and the patients were not on any drugs. Genital porokeratosis is probably underdiagnosed and we believe that these patients should be followed up on account of the precancerous potential of this disease.

Carbon dioxide laser therapy of a widespread epidermal nevus

BACKGROUND AND OBJECTIVE

The treatment of epidermal nevi is difficult and often unsatisfactory. Many therapeutic approaches have been tried, of which the surgical methods including lasers aim to avoid recurrences and hypertrophic scarring. Here we report the case of a widespread, life-impairing epidermal nevus, summarize the available treatment modalities, and discuss CO2 laser therapy with respect to the clinically soft variants of these developmental defects.

STUDY DESIGN/PATIENTS AND METHODS

A patient with a widespread, recurrent, biopsy-proven epidermal nevus was treated with a 10,600-nm CO2 laser. After test treatments in local anaesthesia, four sessions were performed under general anaesthesia each with a follow-up time of 4 years to date.

RESULTS

CO2 laser vaporization resulted in complete removal of the treated nevus without any obvious scarring. The patient is free of recurrence 4 years postoperatively.

CONCLUSION

CO2 laser treatment of epidermal nevi is a useful modality in selected variants.

Porokeratosis of Mibelli on the penis, scrotum and natal cleft

Genital porokeratosis of Mibelli is rare. We report a patient with lesions affecting the penis, scrotum and natal cleft and discuss the aetiology, clinical presentation and treatment of the condition.

Carbon Dioxide laser in the treatment of cutaneous disorders

Experienced gained with the Carbon Dioxide Laser over a two year period is documented. This laser modality has been used successfully for many indications. We believe it is the treatment of choice for conditions such as resistant verrucae, extensive actinic cheilitis or labial leukoplakia, and for the cosmetic removal of widespread facial tumours, some keloid scars and rhinophyma.

Linear porokeratosis: successful treatment with diamond fraise dermabrasion

A patient with linear porokeratosis was successfully treated with diamond fraise dermabrasion. Follow-up evaluation revealed an excellent cosmetic result with adequate repigmentation, no scarring, and no recurrence of lesions. Long-term follow-up will be necessary to determine whether dermabrasion treatment of linear porokeratosis provides adequate prophylaxis against the subsequent development of malignancy.

Disseminated superficial actinic porokeratosis: a clinical study

Disseminated superficial actinic porokeratosis is an autosomal dominant condition that requires sun exposure for full expression. It affects only sun-exposed areas, with relative sparing of the face. In sun-damaged skin of Australians disseminated superficial actinic porokeratosis is commonly mistaken for solar keratosis. Twenty-nine subjects with disseminated superficial actinic porokeratosis were involved in an extensive questionnaire and clinical study. The distribution of lesions was charted on all subjects, with a mean count of 268 lesions per subject. We found no evidence that skin cancer had arisen in disseminated superficial actinic porokeratosis lesions. A review of the etiologic and clinical features of disseminated superficial actinic porokeratosis also is presented.

Linear porokeratosis in two families with disseminated superficial actinic porokeratosis

Two case reports of linear porokeratosis occurring in individuals or families with disseminated, superficial, actinic porokeratosis (DSAP) are presented. Linear porokeratosis and DSAP may be different expressions of one dominantly inherited condition. We reviewed the clinical features of linear porokeratosis and its association with other forms of porokeratosis. The linear form has a potential for carcinomatous change.