Jean Luc Perrot

Reflectance Confocal Microscopy for the Diagnosis of Vulvar Melanoma and Melanosis: Preliminary Results

BACKGROUND In the early stages, vulvar melanoma can mimic vulvar melanosis and therefore the diagnosis is often late and carries a poor prognosis. In vivo reflectance‐mode confocal microscopy (RCM) is an emerging technique that allows noninvasive high‐resolution imaging of the skin and mucosa, but it has not been employed in the study of genital pigmentation. OBJECTIVE To analyze the characteristics of vulvar melanosis and vulvar melanoma using RCM to define the confocal aspects that allow a correct differential diagnosis. METHODS AND MATERIALS Features of eight melanoses and two melanomas of the vulva were analyzed using RCM. RCM diagnosis was then compared with clinical and histologic diagnosis. RESULTS Two major characteristics are associated with vulvar melanosis: papillae rimmed by bright monomorphous cells and possible presence of a few dendritic bright cells in the basal layer of the epithelium. Two major features of vulvar melanoma have been identified: atypical cells in the epithelium and loss of normal architecture of chorion papillae. CONCLUSIONS Reflectance Confocal Microscopy can play a role in noninvasive differentiation between vulvar melanoma and vulvar melanosis, but further broader studies are needed to validate our observations.

Quantitative zymography of matrix metalloproteinases by measuring hydroxyproline: application to gelatinases A and B.

Gelatinases A and B are metalloproteinases involved in the degradation of the extracellular matrix. Detection and quantification of these enzymes in physiological and pathological conditions such as rheumatoid arthritis, tumor invasion and metastasis may be clinically useful. Gelatin zymography is an electrophoretic technique specific for gelatinases. It can be used to detect the activity of both the active and latent forms. We have standardized this technique for the active and latent forms of gelatinase A and for the latent form of gelatinase B. We measured the extent of gelatin degradation with an EDC scanning densitometer (Helena). The value recorded was directly proportional to the amount of enzyme. Gelatinase activity was quantified from the gel by assaying hydroxyproline as an index of gelatin breakdown. Gelatin zymography was found to be useful in characterizing gelatinases A and B by their molecular weights and measuring their specific activity by a standardized analysis of the degraded gelatin substrate.

Laser photodynamic treatment for in situ squamous cell carcinoma of the glans monitored by reflectance confocal microscopy

While mutilating surgery can be avoided with non‐surgical treatment of in situ squamous cell carcinoma (SCC) of the penis, such as photodynamic therapy (PDT), this procedure is not followed by histological evaluation to verify the total removal of the lesion, leading to possible recurrence. We present the first case of in situ penile SCC treated with laser PDT, where the efficacy of the treatment was monitored by reflectance confocal microscopy (RCM) using a handheld camera. In the future RCM may be regarded as a complementary technique to assess the efficacy of non‐surgical treatment of mucous membrane cancers.

Reflectance confocal microscopy for quantification of Sarcoptes scabiei in Norwegian scabies

Background and Objectives  In vivo reflectance‐mode confocal microscopy (RCM) can be used for the diagnosis of scabies. This study quantifies S. scabiei and its eggs and droppings in a patient affected by Norwegian Scabies (NS), and describes their distribution within the epidermis and in different body areas.

Scleredema. A multicentre study of characteristics, comorbidities, course and therapy in 44 patients.

The prognostic and therapeutic features of scleredema are poorly documented.

Optical diagnosis of a metabolic disease: cystinosis

Abstract. Nephropathic cystinosis (NC) is a rare autosomal recessive storage disease characterized by the lysosomal accumulation of cystine crystals throughout the body, particularly in blood cells, the cornea, skin, kidneys, the central nervous system, and the muscles. The skin and the cornea are the most accessible sites to explore, and in vivo reflectance confocal microscopy (IVCM) helps identify crystals in both but does not provide any information to help define their composition. Raman spectroscopy (RS) allows cystine to be easily recognized thanks to its characteristic signature with a band at 499  cm−1. Two dermatology confocal microscopes were used to visualize crystals in both the skin and the ocular surface of a cystinosis patient, and an ex vivo Raman examination of a skin biopsy and of the cornea was performed and removed during a corneal graft to confirm the cystine composition of the crystals. Recently, RS has been performed in vivo and coupled with IVCM. In the future, it is suggested that crystals in NC and other deposits in storage diseases could be identified with this noninvasive in vivo technique that combines IVCM to recognize the deposits and RS to confirm their chemical nature.

Yellow globules in balloon cell naevus.

The balloon cell naevus is a rare variant of melanocytic naevus in which most of the cell population is composed of clear, swollen cells. The dermatoscopic clue is the presence of white globules. We present the first case characterised by yellow globules and describe the correlation with the reflectance confocal microscopy (RCM) and the histological aspect. An 8-year-old child presented with a yellowish-brown congenital papule on her right cheek (Fig. 1). Dermatoscopy demonstrated aggregates of yellowish globules, distributed throughout the lesion background with structureless brown areas and peripheral linear vessels (Fig. 2). RCM (VivaScope 3000, Lucid, MAVIG, Munich, Germany) revealed roundish, moderately refractive large cells with a hyporefractive central part, grouped in well-defined clusters in the superficial dermis (Fig. 3). An excisional biopsy was performed because of the unusual dermatoscopic aspect and because the parents of the child were very anxious and wanted to remove the lesion for cosmetic reasons. The histological examination showed a dermal melanocytic naevus with confluent nests and sheets of large clear cells with a foamy cytoplasm (balloon-cell changes) (Fig. 4a), which were positive for S100 protein and MelanA (Fig. 4b) immunostaining. The balloon cell naevus is characterised by balloon cells that are formed by the progressive vacuolisation of melanocytes because of the enlargement and disintegration of melanosomes. These cells are therefore less pigmented than typical melanocytes and this may result in a clinical and dermatoscopic yellowish appearance. To date, the dermatoscopic aspect of a balloon cell naevus has been reported in only three cases and white globules have been identified as a clue for the diagnosis. We suggest that either yellow globules (as observed in our case) or white globules (as reported in previous cases) found at dermatoscopy may correspond to balloon cell clusters. The difference in colour (white or yellow) may depend on the grade of melanosome degeneration. A brown pigmentation was also present in our patient’s lesion and in the previous reported case, and corresponds to the component of the naevus with normally pigmented melanocytes. The yellow globules observed in balloon cell naevus should be differentiated from those corresponding to sebaceous glands, as seen in sebaceous hyperplasia. In this case the yellowish globular structures have ill-defined borders and cluster together, presenting a popcorn-like appearance. Yellow globules can also correspond to aggregates of sebocytes, as seen in some tumours with sebaceous differentiation such as naevus sebaceous, sebaceous adenoma and keratoacanthoma. These lesions are often characterised by a central crater and elongated radial crown vessels that are not present in balloon cell naevi. Juvenile xanthogranuloma (JXG) should also be considered in the differential diagnosis of yellow globules, especially in children. Moreover, in JXG we can distinguish

Handheld In Vivo Reflectance Confocal Microscopy for the Diagnosis of Eyelid Margin and Conjunctival Tumors

Importance The clinical diagnosis of conjunctival and eyelid margin tumors is challenging, and new noninvasive imaging techniques could be valuable in this field. Objective To assess the diagnostic accuracy of handheld in vivo reflectance confocal microscopy (IVCM) for the diagnosis of eyelid margin and conjunctival tumors. Design A prospective observational study was conducted at University Hospital of Saint-Etienne from January 2, 2011, to December 31, 2016 (inclusion of patients until December 31, 2015, and follow-up until December 31, 2016). A total of 278 consecutive patients with eyelid margin or conjunctival lesions were included. Conjunctival lesions were diagnosed with a conventional clinical examination using a slitlamp and by handheld IVCM. Final diagnoses were established by histopathologic examination for 155 neoformations suspicious for being malignant through clinical and/or IVCM examination that were excised and on follow-up of 12 months or longer for the remaining 140 lesions. Main Outcomes and Measures Sensitivity, specificity, and positive and negative predictive values for malignant tumors of the conjunctiva and eyelid margin were calculated using clinical examination with slitlamp and handheld IVCM. Results In the 278 patients (136 [48.9%] females; mean [SD] age, 59 [21] years), a total of 166 eyelid margin and 129 conjunctival lesions were included in the analysis. Of the 155 excised neoformations with a histopathologic diagnosis, IVCM showed higher sensitivity compared with clinical examination conducted with the slitlamp for malignant tumors of the eyelid margin (98% vs 92%) and conjunctiva (100% vs 88%). The specificity for malignant eyelid margin tumors was higher for IVCM than for slitlamp examination (74% vs 46%), but slightly less for malignant conjunctival tumors (78% vs 88%). Analysis of all neoformations (155 excised and 140 in follow-up) confirmed these differences in the diagnostic accuracy of the clinical examination and IVCM. The presence of hyperreflective Langerhans cells mimicking malignant melanocytes was the main cause for misdiagnosis of malignant conjunctival tumors with IVCM. Conclusions and Relevance Handheld IVCM could be a useful tool for the identification of malignant conjunctival tumors. Further studies are required to confirm the usefulness of this device and identify possible features that can differentiate Langerhans cells from malignant melanocytes to prevent the misdiagnosis of melanoma using IVCM.

'En face' ex vivo reflectance confocal microscopy to help the surgery of basal cell carcinoma of the eyelid

Ex vivo confocal microscopy is a recent imaging technique for the perioperative control of skin tumour margins. Up to date, it has been used in the fluorescence mode and with vertical sections of the specimen margins. The aim of this study was to evaluate its use in the reflectance mode and with a horizontal (‘en face’) scanning of the surgical specimen in a series of basal cell carcinoma of the eyelid.

In vivo confocal microscopy of pine processionary caterpillar hair-induced keratitis.

Purpose: Multimodal imaging of processionary caterpillar hair–induced keratitis with anterior segment optical coherence tomography and in vivo confocal microscopy. Methods: Case report. Results: A 25-year-old woman presented with acute keratitis induced by multiple tiny processionary caterpillar hairs. She initially experienced severe pain and moderate vision loss, which gradually improved within a few weeks. Diagnosis was confirmed by in vivo confocal microscopy showing a pathognomonic image strictly comparable with ex vivo microscopy photography. Conclusions: To the best of our knowledge, this is the first case of corneal in vivo confocal imaging of a caterpillar hair with confirmation by ex vivo microscopy.