V. De Giorgi

Improvement of malignant/benign ratio in excised melanocytic lesions in the ‘dermoscopy era’: a retrospective study 1997–2001

Background  Because of the many limitations of studies based on the diagnostic setting of excised lesions, the impact of dermoscopy (epiluminescence microscopy, dermatoscopy) in melanoma screening during practice remains to be established.

Multidimensional non-linear laser imaging of Basal Cell Carcinoma

We have used a multidimensional non-linear laser imaging approach to visualize ex-vivo samples of basal cell carcinoma (BCC). A combination of several non-linear laser imaging techniques involving fluorescence lifetime, multispectral two-photon and second-harmonic generation imaging has been used to image different skin layers. This approach has elucidated some morphological (supported by histopathological images), biochemical, and physiochemical differences of the healthy samples with respect to BCC ones. In particular, in comparison with normal skin, BCC showed a blue-shifted fluorescence emission, a higher fluorescence response at 800 nm excitation wavelength and a slightly longer mean fluorescence lifetime. Finally, the use of aminolevulinic acid as a contrast agent has been demonstrated to increase the constrast in tumor border detection. The results obtained provide further support for in-vivo non-invasive imaging of Basal Cell Carcinoma.

Nonlinear laser imaging of skin lesions.

We investigated different kinds of human ex-vivo skin samples by combined two-photon intrinsic fluorescence (TPE), second-harmonic generation microscopy (SHG), fluorescence lifetime imaging microscopy (FLIM), and multispectral two-photon emission detection (MTPE). Morphological and spectroscopic differences were found between healthy and pathological skin samples, including tumors. In particular, we examined tissue samples from normal and pathological scar tissue (keloid), and skin tumors, including basal cell carcinoma (BCC), and malignant melanoma (MM). By using combined TPE-SHG microscopy we investigated morphological features of different skin regions. Further comparative analysis of healthy skin and neoplastic samples was performed using FLIM, and MTPE. Finally, we demonstrated the use of methyl-aminolevulinate as a contrast agent to increase the contrast in BCC border detection. The results obtained represent further support for in-vivo noninvasive imaging of diseased skin.

Pattern analysis, not simplified algorithms, is the most reliable method for teaching dermoscopy for melanoma diagnosis to residents in dermatology

Summary Background Simplified algorithms for dermoscopy in melanoma diagnosis were developed in order to facilitate the use of this technique by non‐experts. However, little is known about their reliability compared with classic pattern analysis when taught to untrained observers.

Instrument-, age- and site-dependent variations of dermoscopic patterns of congenital melanocytic naevi: a multicentre study

Background  Recently, we identified and described dermoscopic aspects, present with a higher frequency in congenital melanocytic lesions with respect to acquired naevi. We also classified small‐ and medium‐sized congenital naevi (CN) into nine subtypes according to their macroscopic and dermoscopic aspects.

Combined non-linear laser imaging (two-photon excitation fluorescence microscopy, fluorescence lifetime imaging microscopy, multispectral multiphoton microscopy) in cutaneous tumours : first experiences

Background  Two‐photon excitation (TPE) fluorescence microscopy is a high‐resolution laser‐scanning imaging technique enabling deep imaging inside biological tissues. TPE microscopy has the triple advantage of offering high spatial resolution (250 nm radially, 800 nm axially), high penetration depth inside skin (200mm ), and low photodamage effects. Further, cells and extracellular matrix intrinsically contain a variety of fluorescent molecules (NADH, tryptophan, keratins, melanin, elastin, cholecalciferol and others), so that biological tissues can be imaged by TPE microscopy without any exogenous probe.

Reliability and inter-observer agreement of dermoscopic diagnosis of melanoma and melanocytic naevi

The aim of this study was to analyse the reliability and the inter-observer agreement of dermoscopy in the diagnosis of melanocytic skin lesions. Nine dermatologists, with a different training experience and who routinely used dermoscopy in different hospitals in Italy, evaluated clinical and dermoscopy photographs of 15 melanocytic lesions (four invasive melanomas, four histologically common naevi, and seven naevi with histological atypia). A further series of dermoscopic photographs of 40 melanocytic lesions was evaluated to quantify inter-observer concordance in recognizing dermoscopic criteria. Compared to the true (histological) diagnosis, clinical diagnosis (categories: melanoma, common naevus, atypical naevus) was correct in 40% of cases (range, 27-53%). The percentage raised to 55% (40-73%) by the use of dermoscopy, with an average improvement of 15.6%. Concerning melanoma, clinical diagnosis resulted in a sensitivity of 41.9%, specificity of 77.8%, positive predictive value (PPV) of 36.1%, negative predictive value (NPV) of 81.8%. By using dermoscopy, an improvement of diagnostic performance was found (sensitivity 75%, specificity 88.8%, VPP 71.0%, VPN 90.7%). The inter-observer agreement in melanoma diagnosis, by using dermoscopy, was similar to that obtained by clinical examination (k statistics=0.54 and 0.52, respectively). Concerning dermoscopic criteria, the best agreement among observers was found for pseudopods, a dermoscopic parameter related to the radial growth phase of melanoma. We conclude that dermoscopy is an useful tool for a non-invasive diagnosis of melanocytic skin lesions, improving the diagnostic performance compared to clinical examination.

Dermatoscopy in the diagnosis of pigmented skin lesions: a new semiology for the dermatologist.

Dermatoscopy or epiluminescence microscopy (ELM), is a noninvasive method that enables clinicians to evaluate fully – by means of a magnified oil immersion diascopy – numerous morphological features, not visible with the naked eye, which enhance the diagnosis of nearly all pigmented skin lesions. In recent years, a burst of research activity in this topic has been carried out, dealing with different aspects, and new frontiers, of this technique. First, a continuous refinement of dermatoscopic terminology is undertaken, paying particular attention to the diagnostic performance of dermatoscopy at peculiar anatomical sites and to the building of different dermatoscopic algorithms aimed at a simplified diagnosis of melanoma, even for less experienced observers. Another point of interest concerns the possible role of dermatoscopy in the pre‐operative assessment of melanoma thickness. Finally, promising data about the role of digital equipment in the follow up of melanocytic skin lesions as well as in the automated diagnosis of pigmented skin lesions have been recently reported. This paper should enable readers to become familiar with the procedure and terminology of ELM in the diagnosis of pigmented skin lesions encouraging a greater understanding of different methods (pattern analysis, algorithms) in the diagnosis of melanoma using ELM.

Cutaneous endometriosis: non-invasive analysis by epiluminescence microscopy

Summary The clinical appearance of cutaneous endometriosis can share some features with malignant melanoma, thus representing a possible cause for concern in both patient and clinician. In recent years, the use of epiluminescence microscopy (ELM, dermoscopy) has proved useful in improving the accuracy of diagnosis of pigmented skin lesions. The purpose of this study was to analyse the dermoscopic features of cutaneous endometriosis with histopathological correlation. We studied a case which showed homogeneous reddish pigmentation, regularly distributed. Within this typical pigmentation there were small red globular structures, but more defined and of a deeper hue, which we called ‘red atolls’. ELM thus revealed a distinctive pattern in cutaneous endometriosis.

Melanoma detection rate and concordance between self‐skin examination and clinical evaluation in patients attending a pigmented lesion clinic in Italy

Background The early diagnosis of melanoma is based on the collaboration between dermatologists and family doctors, who filter subjects to be referred to a pigmented lesion clinic (PLC). Following growing media coverage, there is increasing concern in the general population about the risk of the ‘changing mole’, resulting in a progressively increased workload in PLCs.