Disseminated superficial actinic porokeratosis with Bowen's disease

While there have been several reports about the development of malignant neoplasms in porokeratosis of Mibelli and porokeratosis plantaris, palmaris et disseminata, only one case of squamous cell carcinoma in disseminated superficial actinic porokeratosis (DSAP) has been documented. A review is presented of the variants of porokeratosis that have so far been described in the literature as well as the differential diagnosis, genetic aspects and therapy of DSAP. The first case of DSAP with Bowen's disease is presented.     

Linear porokeratosis with multiple squamous cell carcinomas successfully treated by electrochemotherapy

Porokeratosis is a clonal epidermal disorder of keratinization characterized by annular lesions with an atrophic centre and a hyperkeratotic edge. The cornoid lamella is the histopathological hallmark. Six clinical variants are recognized: porokeratosis of Mibelli; disseminated superficial porokeratosis; disseminated superficial actinic porokeratosis (DSAP); porokeratosis plantaris et palmaris disseminata; punctate porokeratosis and linear porokeratosis. Linear porokeratosis is the type most frequently associated with malignant transformation into squamous cell carcinoma (SCC). It is thought to represent a mosaic form of DSAP and has an incidence of less than 1 in 200 000; treatment options are limited. We describe a patient with systematized linear porokeratosis and multiple SCCs who was successfully treated with bleomycin electrochemotherapy (ECT), a form of intralesional chemotherapy. In view of their large number, the individual SCCs were treated with bleomycin ECT. One year post‐treatment the patient remains tumour free. To our knowledge, this is the first case of multiple SCCs treated by ECT in the context of systematized linear porokeratosis. Our case highlights the challenges associated with diagnosing and managing this unusual form of porokeratosis.     

Disseminated superficial actinic porokeratosis. Coexistence with other porokeratotic variants

The coexistence of disseminated superficial actinic porokeratosis (DSAP) with other variants of porokeratosis is rare. We report three such cases: DSAP with porokeratosis of Mibelli; DSAP with linear porokeratosis; and DSAP occurring in the mother of a girl with linear porokeratosis. Although different areas of skin and different family members usually express the same morphological variant, we suggest that the simultaneous expression of two closely linked gene loci could explain the coexistence of different porokeratotic variants.     

Linear porokeratosis of Mibelli and DSAP

Linear porokeratosis and disseminated superficial actinic porokeratosis (DSAP) are clinical variants of porokeratosis. We report the rare coexistence of these two variants. Porokeratosis is a genodermatosis which has at least five different clinical variants; Mibelli, linear, DSAP, plantaris palmaris et disseminata, and punctate (Wade & Ackerman, 1980). All of these manifest the distinctive peripheral keratotic ridge which histologically corresponds to the cornuid lamella. Although lesions of porokeratosis of Mibelli and linear porokeratosis are sometimes seen together in individuals, the coexistence of other porokeratotic variants is rare.     

Disseminated superficial actinic porokeratosis*

A family is analysed in which disseminated superficial actinic porokeratosis (DSAP) occurred in five members. All three children of one generation are affected. Clinical, histopathological and genetic aspects of DSAP are discussed. Disseminated superficial actinic porokeratosis appears to be a clinical variant of porokeratosis of Mibelli. Since DSAP is a genodermatosis inherited as an autosomal dominant it can occur in any geographical location; however excess sunlight can definitely exacerbate the condition.     

Squamous cell carcinoma arising from a lesion of disseminated superficial actinic porokeratosis

We report a 69-year-old man with disseminated superficial actinic porokeratosis (DSAP) who developed a hyperkeratotic lesion on the distal third of the right forearm with the characteristic histopathological findings of squamous cell carcinoma and DSAP. A review of the literature revealed only four similar cases.     

Coexistence of disseminated superficial and giant porokeratosis of Mibelli with squamous cell carcinoma

Porokeratosis of Mibelli is a genetic disease transmitted as an autosomal dominant trait. The giant type of porokeratosis is a relatively rare entity and is associated with an increased risk of malignancy. The aim of this article is to present this rare case of giant porokeratosis associated with squamous cell carcinoma.     

五个汗孔角化病家系的临床和遗传特点

目的 调查5个3种类型汗孔角化病家系的临床和遗传资料,进而分析3种类型汗孔角化病的临床表现和遗传特点。方法 当5个家系先证者的临床诊断明确后(主要诊断依据是特征性皮损和组织病理),现场调查家系资料,对每个家系的家庭成员进行相关临床检查和遗传调查。这5个家系包括3个播散性浅表光线性汗孔角化病(DSAP,共266人,其中患者100例)家系,1个散发性跖汗孔角化病及播散性汗孔角化病(PPPD,共90人,其中患者26例)家系和1个经典斑块型(PM,共34人,其中患者17例)家系。结果 5个家系都为常染色体显性遗传,都具有以边缘呈堤状隆起、中央萎缩的典型皮损,有角化不全细胞柱的病理变化。可分为3种亚型,每一类型各有自身特色。DSAP型是汗孔角化病的一种常见类型,疾病初发年龄较其他类型早(一般8-20岁),初发皮损在颜面部。PPPD型初发年龄为14-20岁,初发皮损为掌跖部或面部,初发皮损为掌跖部者病情较重,初发皮损为面部者病情较轻。PM型的初发年龄较迟,为20-30岁,初发皮损为前臂、手背、耳际和前额等非特定部位。PPPD型家系和PM型家系都有汗孔角化病不同类型的共存现象。结论 汗孔角化病是一种具有不同表现度的常染色体显性遗传病,具有多种临床类型和不同的遗传基础,不同临床类型间既存在一致性也存在差异性,而且不同临床类     

Porokeratosis of Mibelli: Successful treatment with 5 percent topical imiquimod and topical 5 percent 5-fluorouracil

Porokeratosis of Mibelli (PM) is a clonal disorder of keratinization. It clinically presents with one or more annular plaques with central atrophy and elevated keratotic borders. With a 7.5 percent risk of malignancy, PM should be treated to prevent transformation into squamous cell carcinoma, Bowen disease, or basal cell carcinoma. Multiple treatment options are available, however, there is not one universally effective treatment. We describe the successful treatment of porokeratosis of Mibelli of the left calf in an 83-year-old man with topical 5 percent imiquimod and topical 5 percent 5-fluorouracil.     

Disseminated superficial actinic porokeratosis: Appearance associated with photochemotherapy for psoriasis

A patient with chronic psoriasis treated with psoralens plus ultraviolet A (PUVA) developed characteristic lesions of disseminated superficial actinic porokeratosis (DSAP). Since other processes associated with ultraviolet irradiation, including epidermal dysplasia, actinic keratoses, squamous cell carcinomas, and keratoacanthomas, have been reported to result from PUVA, it is possible that her DSAP lesions were induced by this therapy.     

Porokeratosis of Mibelli and immune complex glomerulonephritis

A case of immune complex glomerulonephritis is described in a patient with linear porokeratosis of Mibelli and multiple cutaneous squamous cell carcinomata. Possible aetiological associations are discussed.     

Follicular Porokeratosis at alae Nasi; A Case Report and Short Review of Literature

Porokeratosis are disorders of keratinization, characterized histologically by a parakeratotic column, the cornoid lamellae, and clinically by a distinct peripheral ridge. Porokeratosis usually occurs on the trunk or extremities, and facial lesions are rare. Follicular involvement, identified by follicular localization of cornoid lamellae, is uncommon and described only in association with disseminated superficial actinic porokeratosis (DSAP) and porokeratosis Mibelli (PM). A 34-Year- old woman is presented with asymptomatic 1 cm plaque lesion with hyperkeratotic ridge and depressed center on her nose since three years. Histopathological examination of a biopsy revealed cornoid lamellae confined exclusively to the follicle.     

Porokeratosis in Singapore: an Asian perspective

Porokeratosis is a rare disorder of skin keratinisation characterised by a cornoid lamella. We reviewed its associations with immunosuppression and phototherapy, as well as the risks of malignant progression. This is a retrospective review on all cases of porokeratosis seen at the National Skin Centre, Singapore, between 2000 and 2010. A total of 94 patients were reviewed. Clinical and histological diagnoses were confirmed in 63% patients. Most patients were Chinese (89%) with a mean age of 51.6 years. The male to female ratio was 1.4:1. The four main clinical variants were classical porokeratosis of Mibelli (56%), disseminated superficial actinic porokeratosis (DSAP) (18%), disseminated superficial porokeratosis (DSP) (11%), and linear porokeratosis (13%). Phototherapy-induced porokeratosis, seen in three patients, is rare. Seven cases of porokeratosis occurred in patients who were immunosuppressed. Progression of porokeratosis to malignancy is uncommon and was observed in three patients. The most common treatments included cryotherapy (26.5%) as well as topical steroids or retinoids (38.1%). A good response, defined as clear or almost clear lesions, occurred in 16% patients. The most common presentation of porokeratosis in our review was a middle-aged male patient with an asymptomatic lesion of porokeratosis of Mibelli over the extremities. No particular immunosuppressive drug was implicated. Porokeratosis associated with ultraviolet phototherapy or malignancy is rare. Progression of porokeratosis to malignancy arose in the disseminated variants, with a possible correlation with age. This is the largest institutional retrospective review of porokeratosis to date and highlights the major epidemiological characteristics of this condition.     

Cytogenetic studies in a patient with porokeratosis of Mibelli, multiple cancers and a forme fruste of Werner''s syndrome

A 49-year-old man with extensive porokeratosis of Mibelli (PM) developed a squamous cell carcinoma and several carcinomas-in-situ within the lesional skin. The patient also had diabetes mellitus and a short stature with a prematurely aged appearance. The patient's father and two siblings also had PM. The patient died from metastatic squamous cell carcinoma, and at autopsy an adenocarcinoma of the descending colon was also found. Fibroblasts cultured from both the PM-affected and unaffected skin showed chromosomal abnormalities and a decreased lifespan. Cellular sensitivity to ultraviolet rays measured by unscheduled DNA synthesis and colony-forming ability were within normal limits. An association with a forme fruste of Werner's syndrome was suspected.     

Verrucous porokeratosis of Mibelli on the buttocks mimicking psoriasis

The typical presentation of porokeratosis of Mibelli is of a solitary plaque with a prominent raised border cleaved by a central furrow. The central portion of the plaque is usually slightly atrophic. The plaques vary in size from a few millimeters to several centimeters in diameter and tend to be acrally distributed, though they can occur on any part of the body. We report an unusual case of verrucous porokeratosis of Mibelli, localized to the natal cleft, that mimicked psoriasis. This entity, though unusual, is not unique. Two similar cases of verrucous porokeratosis of Mibelli limited to the natal cleft region and resembling psoriasis have been reported in the British literature. Verrucous porokeratosis of Mibelli localized to the natal cleft appears to be a distinct clinical entity that can mimic psoriasis. Better recognition of this form of porokeratosis of Mibelli may result in earlier diagnosis and initiation of appropriate therapy.     

Bildgebende Diagnostik der aktinischen Porokeratose mittels optischer Kohärenztomographie (OCT)

Disseminated superficial actinic porokeratosis (DSAP) is a rare, genetically heterogeneous skin disorder. We report a case of a 73-year-old female patient who was diagnosed with DSAP by optical coherence tomography (OCT) and histology. During the last 4 years prior to diagnosis, she had developed numerous (pre)malignant lesions of the skin of the lower legs including actinic keratoses, squamous cell carcinomas and Bowen's disease. DSAP lesions and actinic keratoses were resistant to topical treatment with imiquimod and retinoids, but improved with photodynamic therapy (PDT).     

Clinical Study of Porokeratosis Associated with Immunosuppressive Therapy in Renal Transplant Recipients

BackgroundThe etiology of porokeratosis (PK) remains unknown, but immunosuppression is known to be a factor in the pathogenesis of PK and it may also exacerbate PK.ObjectiveThe aim of this study was to examine the clinical characteristics of PK associated with immunosuppressive therapy in renal transplant recipients.MethodsA total of 9 renal transplant patients diagnosed with biopsy-proven PK from January 2001 to December 2006 were enrolled. The authors analyzed the patient and medication histories, clinical characteristics, and associated diseases.ResultsThe ages of the 9 patients ranged from 38 to 67 years (mean 52 years). All received multi-drug regimens comprised of two or three immunosuppressive agents (steroids, cyclosporine, mycophenolate mofetil, azathioprine and/or tacrolimus). Times between transplantation and the onset of PK ranged from 2 to 9 years (mean 4.1 years). No family history of PK or a history of intense sun-exposure was elicited. The number of the lesions was less than ten in 8 of the 9. Lesions were mainly located in the extremities, though some affected the trunk or neck (3). Three patients had disseminated superficial actinic PK (DSAP), PK Mibelli, or both types. Associated diseases included verruca (4), recurrent herpes simplex (1), actinic keratosis (1), and cutaneous B cell lymphoma (1).ConclusionThe three clinical patterns of PK occurred equally in our patients, namely, coexistent PK Mibelli and DSAP, or the DSAP and Mibelli types as independent forms. Our findings support the notion that the different variants of PK be viewed as parts of a heterogeneous clinical spectrum. Further studies are needed in order to establish the clinical patterns of PK in immunosuppressed patients.     

Cultured skin fibroblasts derived from three patients with disseminated superficial actinic porokeratosis (DSAP) are hypersensitive to the lethal effects of X-radiation but not to those of ultraviolet (UV) light

Abstract Disseminated superficial actinic porokeratosis (DSAP), skin lesions of which are known to be induced by ultraviolet (UV) light, does not develop into skin cancer as frequently as other types of porokeratosis (PK) To establish the cellular basis of this characteristic of DSAP. we examined the colony-forming ability of UVC light- or X-ray-irradiated cultured fibroblasts derived from DSAP patients' skin. Sensitivity to the lethal effects of UV light was not significantly different between 3 DSAP and 5 control cell strains. In contrast, DSAP cell strains were significantly hypersensitive to the lethal effects of X-radiation, although the sensitivity was less than that of cell strains from other types of PK patients. The results indicate that the actinic character of DSAP is not reflected in the cellular response to the lethal effects of UV light, but suggest that DSAP shares X-ray sensitivity, which is probably associated with the cancer-prone nature of PK.     

Bowen disease associated with porokeratosis of Mibelli.

A 73-year-old woman developed Bowen precancerous dermatosis in an area of porokeratosis of Mibelli on her leg. This is the fourth reported case of Bowen disease arising from porokeratosis of Mibelli. The recent literature indicates that porokeratosis of Mibelli may be due to an abnormal clone of cells, predisposing affected individuals to development of malignant neoplasms over the involved areas.     

Novel dermatologic uses of the immune response modifier imiquimod 5% cream

Imiquimod is the first of a new class of drugs to emerge in the treatment of various dermatologic disorders. As an immune response modifier, it has been shown to have potent antiviral and antitumor properties through the stimulation of innate and cell mediated immune pathways. It is currently approved for the treatment of external genital and perianal warts, but has also been found to be an effective treatment for a host of other virus-associated dermatologic lesions, including common and flat warts, molluscum contagiosum and herpes simples 2. Oncological lesions showing improvement with the use of imiquimod include basal cell carcinoma, actinic keratosis, squamous cell carcinoma in situ, malignant melanoma, cutaneous T-cell lymphoma, and cutaneous extramammary Paget's disease. Recent case studies have also found this product to be effective for treating keloids, infantile hemangiomas, porokeratosis of Mibelli, leishmanisis, and tattoo removal. This extensive array of disorders treated successfully with imiquimod warrants further study of this novel and valuable drug.