Conventional light microscopy (CLM) has classically been the basic tool to teach histology and pathology. In recent years, whole-slide imaging (WSI), which consists of generating a high-magnification digital image of an entire histological glass slide, has emerged as a useful alternative to CLM offering a myriad of opportunities for education. Navigation through the digitized slides closely simulates viewing glass slides with a microscope and is also referred to as virtual microscopy. WSI has many advantages for education. Students feel more comfortable with its use, and it can be used in any classroom as it only requires a computer with Internet access and it allows remote access from anywhere and from any device. WSI can be used simultaneously by a large number of people, stimulating cooperation between students and improving the interaction with the teachers. It allows making marks and annotations on specific fields, which enable specific directed questions to the teacher. Finally, WSI supports are cost-effective compared with CLM. Consequently, WSI has begun to replace CLM in many institutions. WSI has shown to be an extremely useful tool for undergraduate education (medical, dental and veterinary schools), for the training of residents of pathology, tele-education and in tumor boards.

Summary Confocal microscopy with in vivo and ex vivo modalities has been used in the evaluation of skin cancer and other dermatological disorders. Recent developments in ex vivo confocal microscopy allow for faster pathology assessment with greater accuracy by the visualization of cellular and architectural details, similarly to standard pathology, in either paraffin‐embedded or frozen samples. They include the possibility of multimodal confocal microscopy using different lasers and fusion images. New staining protocols including immunostaining, with no damage to conventional histopathology preparation, have been recently described in melanocytic tumours and inflammatory skin diseases. Digital staining with haematoxylin and eosin is also incorporated in the new devices. In this review the applications of ex vivo confocal microscopy will be presented with the description of the technique and the technology, clinical evidence in dermatology and other fields, and further applications.

The rosette structure is a dermoscopic sign visible under polarized light, characterized by 4 white points arranged as a 4-leaf clover. It has been mainly described in facial sun-damaged skin and actinic keratosis, although it has also been found in squamous and basal cell carcinomas, and in 2 cases of hypomelanotic melanomas. We describe 2 different cases of pigmented incipient melanomas with the presence of multiple rosettes and shiny white structures on dermoscopy. In the reflectance confocal microscope they exhibit a disarranged epidermal architecture with atypical and dendritic cells. Histological examination showed focal hyperkeratosis and a normal corneal layer presented alternatively. To our knowledge this is the first description of rosette structures in pigmented melanomas. Based on a proper dermoscopic- confocal-histopathological correlation, we hypothesize that rosettes could correspond to optic phenomena due to changes in the superficial epidermal reaction and in the acrosyringia.

Vulvar squamous cell carcinoma arising on human papillomavirus-independent precursors mimicking high-grade squamous intra-epithelial lesion: a distinct and highly recurrent subtype of vulvar cancer Aims: Each category of vulvar squamous cell carcinoma (VSCC), human papillomavirus (HPV)associated and HPV-independent, arises on a specific intra-epithelial precursor: high-grade squamous intraepithelial lesions (HSIL) and differentiated vulvar intra-epithelial neoplasia (dVIN), respectively. However, a subset of HPV-independent VSCC arises on an intra-epithelial precursor closely mimicking HSIL. We aimed to explore the clinicopathological features of the HPV-independent tumours with HSIL-like lesions and compare them with HPV-independent VSCC with dVIN and HPV-associated tumours with HSIL. Methods and results: We retrospectively identified 105 cases of surgically treated VSCC with adjacent intra-epithelial precursors. The cases were classified into three groups based on the HPV status and the adjacent precursor identified: (i) HPV-associated VSCC with HSIL (n = 26), (ii) HPV-independent VSCC with dVIN lesions (n = 54) and (iii) HPV-independent VSCC with HSIL-like lesions (n = 25). We analysed the histological and clinical features including the recurrencefree survival and disease-specific survival in the three groups. Patients with HPV-independent VSCC with HSIL-like lesions and with dVIN were older than patients with HPV-associated VSCC (76 and 77 versus 66 years, respectively, P < 0.001). HPV-independent VSCC with HSIL-like lesions recurred more frequently [hazard ratio (HR) = 3.87; P < 0.001] than HPVindependent VSCC with dVIN (HR = 2.27; P = 0.1) and HPV-associated VSCC (HR = 1). In the multivariate analysis, HPV-independent VSCC with HSIL-like lesions remained significant for recurrence. No differences in disease-specific survival were observed between the three groups. Conclusions: Even though VSCC with HSIL-like lesions are not associated with higher mortality, they are more likely to recur and might benefit from more intensive treatment strategies and closer surveillance after treatment.

In this clinically and dermoscopically challenging subset of vulvar pigmentations, RCM appears relevant for initial extensive evaluation, especially to target initial biopsy sampling, and to perform non-invasive monitoring of foci of melanocytic hyperplasia.