Federica Arginelli

Multiphoton Laser Tomography and Fluorescence Lifetime Imaging of Melanoma: Morphologic Features and Quantitative Data for Sensitive and Specific Non-Invasive Diagnostics

Multiphoton laser tomography (MPT) combined with fluorescence lifetime imaging (FLIM) is a non-invasive imaging technique, based on the study of fluorescence decay times of naturally occurring fluorescent molecules, enabling a non-invasive investigation of the skin with subcellular resolution. The aim of this retrospective observational ex vivo study, was to characterize melanoma both from a morphologic and a quantitative point of view, attaining an improvement in the diagnostic accuracy with respect to dermoscopy. In the training phase, thirty parameters, comprising both cytological descriptors and architectural aspects, were identified. The training set included 6 melanomas with a mean Breslow thickness±S.D. of 0.89±0.48 mm. In the test phase, these parameters were blindly evaluated on a test data set consisting of 25 melanomas, 50 nevi and 50 basal cell carcinomas. Melanomas in the test phase comprised 8 in situ lesions and had a mean thickness±S.D. of 0.77±1.2 mm. Moreover, quantitative FLIM data were calculated for special areas of interest. Melanoma was characterized by the presence of atypical short lifetime cells and architectural disorder, in contrast to nevi presenting typical cells and a regular histoarchitecture. Sensitivity and specificity values for melanoma diagnosis were 100% and 98%, respectively, whereas dermoscopy achieved the same sensitivity, but a lower specificity (82%). Mean fluorescence lifetime values of melanocytic cells did not vary between melanomas and nevi, but significantly differed from those referring to basal cell carcinoma enabling a differential diagnosis based on quantitative data. Data from prospective preoperative trials are needed to confirm if MPT/FLIM could increase diagnostic specificity and thus reduce unnecessary surgical excisions.

Multiphoton laser tomography and fluorescence lifetime imaging of basal cell carcinoma: morphologic features for non-invasive diagnostics.

Multiphoton laser tomography (MPT) combined with fluorescence lifetime imaging (FLIM) is a non‐invasive imaging technique, which gives access to the cellular and extracellular morphology of the skin. The aim of our study was to assess the sensitivity and specificity of MPT/FLIM descriptors for basal cell carcinoma (BCC), to improve BCC diagnosis and the identification of tumor margins. In the preliminary study, FLIM images referring to 35 BCCs and 35 healthy skin samples were evaluated for the identification of morphologic descriptors characteristic of BCC. In the main study, the selected parameters were blindly evaluated on a test set comprising 63 BCCs, 63 healthy skin samples and 66 skin lesions. Moreover, FLIM values inside a region of interest were calculated on 98 healthy skin and 98 BCC samples. In the preliminary study, three epidermal descriptors and 7 BCC descriptors were identified. The specificity of the diagnostic criteria versus ‘other lesions’ was extremely high, indicating that the presence of at least one BCC descriptor makes the diagnosis of ‘other lesion’ extremely unlikely. FLIM values referring to BCC cells significantly differed from those of healthy skin. In this study, we identified morphological and numerical descriptors enabling the differentiation of BCC from other skin disorders and its distinction from healthy skin in ex vivo samples. In future, MPT/FLIM may be applied to skin lesions to provide direct clinical guidance before biopsy and histological examination and for the identification of tumor margins allowing a complete surgical removal.

Multiphoton laser microscopy and fluorescence lifetime imaging for the evaluation of the skin.

Multiphoton laser microscopy is a new, non-invasive technique providing access to the skin at a cellular and subcellular level, which is based both on autofluorescence and fluorescence lifetime imaging. Whereas the former considers fluorescence intensity emitted by epidermal and dermal fluorophores and by the extra-cellular matrix, fluorescence lifetime imaging (FLIM), is generated by the fluorescence decay rate. This innovative technique can be applied to the study of living skin, cell cultures and ex vivo samples. Although still limited to the clinical research field, the development of multiphoton laser microscopy is thought to become suitable for a practical application in the next few years: in this paper, we performed an accurate review of the studies published so far, considering the possible fields of application of this imaging method and providing high quality images acquired in the Department of Dermatology of the University of Modena.

Diagnosis of BCC by multiphoton laser tomography

Multiphoton Laser Tomography (MPT) is a non‐linear optical technique that gives access to morphology and structure of both cells and extracellular matrix of the skin through the combination of autofluorescence imaging and second harmonic generation (SHG). The aim of this study was to identify MPT descriptors on ex vivo specimens of basal cell carcinoma (BCC) to assess the sensitivity and specificity of these criteria for the diagnosis of BCC and its differentiation from other skin tumours, inflammatory diseases and healthy skin.

High-resolution imaging of basal cell carcinoma: a comparison between multiphoton microscopy with fluorescence lifetime imaging and reflectance confocal microscopy.

The aim of this study was to compare morphological aspects of basal cell carcinoma (BCC) as assessed by two different imaging methods: in vivo reflectance confocal microscopy (RCM) and multiphoton tomography with fluorescence lifetime imaging implementation (MPT‐FLIM).

High resolution diagnosis of common nevi by multiphoton laser tomography and fluorescence lifetime imaging

Multiphoton Laser Tomography (MPT) has developed as a non‐invasive tool that allows real‐time observation of the skin with subcellular resolution. MPT is readily combined with time resolved detectors to achieve fluorescence lifetime imaging (FLIM). The aim of our study was to identify morphologic MPT/FLIM descriptors of melanocytic nevi, referring to cellular and architectural features.

Dermoscopic yellow structures in basal cell carcinoma

Yellowish structures in dermoscopy comprise milia‐like cysts (MLCs) and yellow lobular‐like structures.

High magnification digital dermoscopy of basal cell carcinoma: a single-centre study on 400 cases.

The aim of this study was to assess the frequency of classic dermoscopic basal cell carcinoma (BCC) features and the sensitivity of new descriptors, such as light brown nests (homogeneous and structured) only visible employing a high magnification digital videomicroscope. A retrospective analysis of 2,024 highly magnified digital images referring to 400 BCCs was performed by 3 independent observers, who assessed 11 classic BCC descriptors and the new ones. Light brown nests were detected in 40.5% of BCCs. Homogeneous ones were observable in 17.8%, and structured nests in 32.8%. Light brown nests were visible in 14.3% of non-pigmented lesions, whereas in the pigmented groups these were observed in 42-54% of the cases. We suggest that brown nests described in this study may improve early recognition of superficial BCCs and of non-pigmented or slightly pigmented ones that may lack classic dermoscopic patterns.

Improving diagnostic sensitivity of combined dermoscopy and reflectance confocal microscopy imaging through double reader concordance evaluation in telemedicine settings: A retrospective study of 1000 equivocal cases

Background Reflectance confocal microscopy (RCM) is an imaging device that permits non-invasive visualization of cellular morphology and has been shown to improve diagnostic accuracy of dermoscopically equivocal cutaneous lesions. The application of double reader concordance evaluation of dermoscopy-RCM image sets in retrospective settings and its potential application to telemedicine evaluation has not been tested in a large study population. Objective To improve diagnostic sensitivity of RCM image diagnosis using a double reader concordance evaluation approach; to reduce mismanagement of equivocal cutaneous lesions in retrospective consultation and telemedicine settings. Methods 1000 combined dermoscopy-RCM image sets were evaluated in blind by 10 readers with advanced training and internship in dermoscopy and RCM evaluation. We compared sensitivity and specificity of single reader evaluation versus double reader concordance evaluation as well as the effect of diagnostic confidence on lesion management in a retrospective setting. Results Single reader evaluation resulted in an overall sensitivity of 95.2% and specificity of 76.3%, with misdiagnosis of 8 melanomas, 4 basal cell carcinomas and 2 squamous cell carcinomas. Combined double reader evaluation resulted in an overall sensitivity of 98.3% and specificity of 65.5%, with misdiagnosis of 1 in-situ melanoma and 2 basal cell carcinomas. Conclusion Evaluation of dermoscopy-RCM image sets of cutaneous lesions by single reader evaluation in retrospective settings is limited by sensitivity levels that may result in potential mismanagement of malignant lesions. Double reader blind concordance evaluation may improve the sensitivity of diagnosis and management safety. The use of a second check can be implemented in telemedicine settings where expert consultation and second opinions may be required.

Long-term efficacy of high doses of intravenous immunoglobulins in generalized scleromyxoedema: Case report

Scleromyxoedema is a rare disease with a progressive and disabling course involving dermal deposition of mucin and fibroblast proliferation; it is characterized clinically by a diffuse papular eruption, skin thickening, oedema and decreased skin flexibility, especially of the face and hands. Current therapy options are based on evidence from a limited number of case reports. The clinical manifestations and treatment of a 64-year-old man affected by scleromyxoedema with severe skin involvement of the face, arms and hands, decreased mouth opening and hypomotility of the fingers are reported. Dysphagia, asthenia and immunoglobulin G lambda monoclonal gammopathy were also present. Previous treatment with topical and systemic corticosteroids, psoralen plus ultraviolet A radiation therapy, plasmapheresis, extracorporeal photochemotherapy, hydroxychloroquine and cyclophosphamide had been unsuccessful. Treatment with intravenous immunoglobulins at a dosage of 2 g/kg monthly was started. Considerable improvements were observed after seven cycles of therapy, with recovery of skin elasticity, an increase in facial mimic movement, restoration of joint function and improvement in the modified Rodnan score. There were no observed side-effects. The patient remains in remission on monthly maintenance intravenous immunoglobulins, 2 years after initial treatment.