Squamous cell carcinoma arising from giant porokeratosis and rare postoperative recurrence and metastasis: A case report

A Case of Squamous Cell Carcinoma Arising in Disseminated Superficial Porokeratosis

Porokeratosis (PK), characterized by keratotic lesions with an atrophic center and a prominent peripheral ridge, with a typical histological hallmark, namely, the cornoid lamella, has two forms: disseminated and localized. While PK often converts into squamous cell carcinoma (SCC), conversion from disseminated superficial porokeratosis (DSP) alone is rarely reported except for one case in which DSP and LP coexisted and converted to SCC. Here, we report the case of a patient with SCC converted from DSP alone, presenting with coin-sized macules on the bottom right of his waist that developed into an ulcer at the center. The patient underwent radiation therapy, which effectively treated the SCC but did not resolve the PK. This article highlights regular follow-up and undergo comprehensive diagnosis, both of which are beneficial to enable early detection and management of DSP that has converted to into SCC; in addition, standardized medical treatment may help improve the treatment therapeutic effect of in similar diseases.

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.

A case of squamous cell carcinoma arising in a giant porokeratosis previously diagnosed as psoriasis

Porokeratosis (PK) is a disorder of keratinization with a clinical presentation of an atrophic center surrounded by a hyperkeratotic border. Lesions of porokeratosis carry a risk of malignant transformation with giant porokeratosis (GPK) being a high-risk variant. We report a case in which a single, large, erythematous, scaly plaque in an immunocompromised patient showed initial histopathological features consistent with psoriasis and subsequent histological features consistent with GPK. This plaque underwent malignant transformation to SCC on three occasions. This case highlights that specimens taken from central portions of porokeratosis may resemble a variety of dermatoses histologically, including psoriasis, resulting in misdiagnosis as seen in our patient. When a patient presents with a diagnosis previously made that isn’t responding to therapy as expected, repeat biopsy is appropriate.

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.