Background: Human papillomavirus (HPV) has long been proposed as a cofactor in the pathogenesis of cutaneous squamous cell carcinoma (cSCC). More recently, the striking clinico-pathological features of cSCCs that complicate treatment of metastatic melanoma with inhibitors targeting BRAF mutations (BRAFi) has prompted speculation concerning a pathogenic role for oncogenic viruses. Here, we investigate HPV and human polyomaviruses (HPyV) and correlate with clinical, histologic, and genetic features in BRAFi-associated cSCC.Materials and Methods: Patients receiving BRAFi treatment were recruited at Barts Health NHS Trust. HPV DNA was detected in microdissected frozen samples using reverse line probe technology and degenerate and nested PCR. HPV immunohistochemistry was performed in a subset of samples. Quantitative PCR was performed to determine the presence and viral load of HPyVs with affinity for the skin (HPyV6, HPyV7, HPyV9, MCPyV, and TSPyV). These data were correlated with previous genetic mutational analysis of H, K and NRAS, NOTCH1/2, TP53, CDKN2A, CARD11, CREBBP, TGFBR1/2. Chromosomal aberrations were profiled using single nucleotide polymorphism (SNP) arrays.Results: Forty-five skin lesions from seven patients treated with single agent vemurafenib in 2012–2013 were analyzed: 12 cSCC, 19 viral warts (VW), 2 actinic keratosis (AK), 5 verrucous keratosis/other squamoproliferative (VK/SP) lesions, one melanocytic lesion and 6 normal skin samples. Significant histologic features of viral infection were seen in 10/12 (83%) cSCC. HPV DNA was detected in 18/19 (95%) VW/SP, 9/12 (75%) cSCC, 4/5 (80%) SP, and 3/6 (50%) normal skin samples and in 1/12 cases assessed by immunohistochemistry. HPyV was co-detected in 22/30 (73%) of samples, usually at low viral load, with MCPyV and HPyV7 the most common. SNP arrays confirmed low levels of chromosomal abnormality and there was no significant correlation between HPV or HPyV detection and individual gene mutations or overall mutational burden.Conclusion: Despite supportive clinicopathologic evidence, the role for HPV and HPyV infection in the pathogenesis of BRAFi-induced squamoproliferative lesions remains uncertain. Synergistic oncogenic mechanisms are plausible although speculative. Nonetheless, with the prospect of a significant increase in the adjuvant use of these drugs, further research is justified and may provide insight into the pathogenesis of other BRAFi-associated malignancies.

This is a prospective study to find out whether an interactive large-group case-based teaching approach combined with small-group bedside teaching improves student satisfaction and learning outcome in a practical dermatology course. During two consecutive terms a rotating system of large-group interactive case-study-method teaching with two tutors (one content expert, one process facilitator) and bedside teaching with randomly appointed tutors was evaluated with a nine-item questionnaire and multiple-choice test performed at the beginning and the end of the course (n = 204/231 students evaluable). The results of three different didactic approaches utilized over the prior year served as a control. The interactive course was rated significantly better (p < 0.0001) than the standard course with regard to all items. The aggregate mark given by the students for the whole course was 1.58-0.61 (mean +/- SD, range 1 (good)-5 (poor)). This was significantly better than the standard course (p < 0.0001) and not different from small-group teaching approaches. The mean test results in the final examination improved significantly (p < 0.01). The combination of large-group interactive teaching and small-group bedside teaching was well accepted, improved the learning outcome, was rated as good as a small-group didactic approach and needed fewer resources in terms of personnel.

Skin bleaching, also known as skin lightening, is the deliberate lightening of an individual's skin tone without medical supervision. The causes are complex, multifactorial and often intertwined, although the unifying themes centre around a belief that lighter skin denotes an individual of higher status, socioeconomic background or physical beauty, than their darker-skinned counterpart. Skin lightening is achieved using agents that block the production of melanin and often contain drugs such as hydroquinone, superpotent topical steroids or mercury. These drugs can cause serious local and systemic complication. Skin-lightening compounds are illegal in most countries throughout the world; however the industry is worth billions of dollars annually, and the agents can be easily obtained by individuals seeking to lighten their skin. Dermatologists are in a unique position to identify those at risk of using skin-bleaching agents, manage complications and give advice on the physiological variation in pigmentation and how to avoid using skin-lightening agents to treat dermatological conditions. To manage the belief that lighter skin is better, societal level change is required to ensure that people of all skin tones are represented in the media.

Streptococcus pyogenes M/emm3 strains have been epidemiologically linked with enhanced infection severity and risk of streptococcal toxic shock syndrome (STSS), a syndrome triggered by superantigenic stimulation of T cells. Comparison of S. pyogenes strains causing STSS demonstrated that emm3 strains were surprisingly less mitogenic than other emm-types (emm1, emm12, emm18, emm28, emm87, emm89) both in vitro and in vivo, indicating poor superantigenic activity. We identified a 13 bp deletion in the superantigen smeZ gene of all emm3 strains tested. The deletion led to a premature stop codon in smeZ, and was not present in other major emm-types tested. Expression of a functional non-M3-smeZ gene successfully enhanced mitogenic activity in emm3 S. pyogenes and also restored mitogenic activity to emm1 and emm89 S. pyogenes strains where the smeZ gene had been disrupted. In contrast, the M3-smeZ gene with the 13 bp deletion could not enhance or restore mitogenicity in any of these S. pyogenes strains, confirming that M3-smeZ is non-functional regardless of strain background. The mutation in M3-smeZ reduced the potential for M3 S. pyogenes to induce cytokines in human tonsil, but not during invasive infection of superantigen-sensitive mice. Notwithstanding epidemiological associations with STSS and disease severity, emm3 strains have inherently poor superantigenicity that is explained by a conserved mutation in smeZ.

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.