Pietro Rubegni

Automated diagnosis of pigmented skin lesions.

Since advanced melanoma remains practically incurable, early detection is an important step toward a reduction in mortality. High expectations are entertained for a technique known as dermoscopy or epiluminescence light microscopy; however, evaluation of pigmented skin lesions by this method is often extremely complex and subjective. To obviate the problem of qualitative interpretation, methods based on mathematical analysis of pigmented skin lesions, such as digital dermoscopy analysis, have been developed. In the present study, we used a digital dermoscopy analyzer (DBDermo‐Mips system) to evaluate a series of 588 excised, clinically atypical, flat pigmented skin lesions (371 benign, 217 malignant). The analyzer evaluated 48 parameters grouped into 4 categories (geometries, colors, textures and islands of color), which were used to train an artificial neural network. To evaluate the diagnostic performance of the neural network and to check it during the training process, we used the error area over the receiver operating characteristic curve. The discriminating power of the digital dermoscopy analyzer plus artificial neural network was compared with histologic diagnosis. A feature selection procedure indicated that as few as 13 of the variables were sufficient to discriminate the 2 groups of lesions, and this also ensured high generalization power. The artificial neural network designed with these variables enabled a diagnostic accuracy of about 94%. In conclusion, the good diagnostic performance and high speed in reading and analyzing lesions (real time) of our method constitute an important step in the direction of automated diagnosis of pigmented skin lesions.

Melanoma Computer-Aided Diagnosis Reliability and Feasibility Study

Background: Differential diagnosis of melanoma from melanocytic nevi is often not straightforward. Thus, a growing interest has developed in the last decade in the automated analysis of digitized images obtained by epiluminescence microscopy techniques to assist clinicians in differentiating early melanoma from benign skin lesions. Purpose: The aim of this study was to evaluate diagnostic accuracy provided by different statistical classifiers on a large set of pigmented skin lesions grabbed by four digital analyzers located in two different dermatological units. Experimental Design: Images of 391melanomas and 449 melanocytic nevi were included in the study. A linear classifier was built by using the method of receiver operating characteristic curves to identify a threshold value for a fixed sensitivity of 95%. A K-nearest-neighbor classifier, a nonparametric method of pattern recognition, was constructed using all available image features and trained for a sensitivity of 98% on a large exemplar set of lesions. Results: On independent test sets of lesions, the linear classifier and the K-nearest-neighbor classifier produced a mean sensitivity of 95% and 98% and a mean specificity of 78% and of 79%, respectively. Conclusions: In conclusion, our study suggests that computer-aided differentiation of melanoma from benign pigmented lesions obtained with DB-Mips is feasible and, above all, reliable. In fact, the same instrumentations used in different units provided similar diagnostic accuracy. Whether this would improve early diagnosis of melanoma and/or reducing unnecessary surgery needs to be demonstrated by a randomized clinical trial.

Extracorporeal photochemotherapy restores Th1/Th2 imbalance in patients with early stage cutaneous T‐cell lymphoma

Extracorporeal photochemotherapy (ECP) has been shown to be a potent activator of peripheral blood macrophages because it causes a marked release of macrophage‐dependent proinflammatory cytokines, and it is therefore currently considered to be a safe and non‐toxic immunomodulatory treatment. On this basis we studied the function of peripheral blood mononuclear cells (PBMC) in eight patients with early stage (Ib) cutaneous T‐cell lymphoma (CTCL), before and 1 year after ECP, together with their clinical and histological responses. In particular we evaluated in vitro phytohaemagglutinin (PHA)‐stimulated proliferation and production of interleukin‐4 (IL‐4) and interferon‐&ggr; (IFN‐&ggr;) as well as lipopolysaccharide (LPS)‐induced production of IL‐12. Before treatment we observed that PBMC of patients produced significantly higher levels of IL‐4 and lower levels of IFN‐&ggr; and IL‐12 than those of healthy control subjects. After 1 year of ECP, IL‐4, IFN‐&ggr; and IL‐12 production no longer differed from that of control subjects. Moreover, we observed a good clinical result matched by histological response. Our data confirm that early‐ stage CTCL patients show a predominantly type‐2 immune response that might be responsible for several immunological abnormalities found in this disease. We have demonstrated that ECP reverses the T‐helper type 1/T‐helper type 2 (Th1/Th2) imbalance and may therefore be considered an efficient biological response modifier.

Slow-growing melanoma: a dermoscopy follow-up study

Background  Recent evidence suggests that melanoma is a family of different tumours with varying abilities to grow and metastasize. Trends in melanoma epidemiology show a strong increase in the incidence of thin melanoma, with no corresponding increase in mortality or incidence of thick melanoma. We initially evaluated five cases and found that none had baseline features suggestive of melanoma; excision was performed based on slight changes visible only in side‐by‐side comparisons of dermoscopic images.

Dysplastic naevus vs. in situ melanoma: digital dermoscopy analysis.

Background  To date, much confusion exists about the biological significance of dysplastic naevi and about the relationship between melanocytic dysplasia and clinical atypia.

Role of extracorporeal photochemotherapy in patients with refractory chronic graft-versus-host disease

Recent studies suggest that extracorporeal photochemotherapy (ECP) may be beneficial in patients with steroid‐refractory chronic graft‐versus‐host disease (cGvHD). However, it is not yet clear whether certain conditions, such as age, mode of onset of cGvHD etc., influence clinical response and whether certain affected organs are more sensitive to ECP than others. We analysed the main clinical and laboratory parameters related to evolution of the disease in 32 steroid‐refractory cGvHD patients, to identify any useful response predictors to ECP. ECP affected the course of the disease positively in 78% (25/32) of our cases.

Mechanism of action of extracorporeal photochemotherapy in chronic graft-versus-host disease

Chronic graft‐versus‐host disease (GvHD) affects 50% of long‐term bone marrow transplant survivors and remains a cause of major long‐term morbidity in these patients despite aggressive therapy. Extracorporeal photochemotherapy (ECP), considered as an effective treatment for patients with erythrodermic cutaneous T‐cell lymphoma (CTCL), has recently been used successfully in the treatment of GvHD. One of the most intriguing aspects of ECP is its ability to induce two apparently opposite effects: activation of the immune system against neoplastic cells (as in CTCL) and downregulation of the activity of T‐cell clones in autoimmune diseases (as in systemic sclerosis, systemic lupus erythematosus and pemphigus vulgaris) and autoallogeneic immune responses (as in GvHD and allograft rejection). Only a better and more complete understanding of the various mechanisms involved will enable this interesting new therapy to be made more effective and selective.

Evaluation of tumour-infiltrating CD4+CD25+FOXP3+ regulatory T cells in human cutaneous benign and atypical naevi, melanomas and melanoma metastases.

Background  CD4+CD25+FOXP3+ regulatory T cells (Tregs) are thought to induce immunotolerance in melanoma. They have not yet been investigated in the entire spectrum of melanocytic cutaneous lesions within a tumour site.

Dermoscopy Key Points: Recommendations from the International Dermoscopy Society

J. Bowling G. Argenziano A. Azenha J. Bandic R. Bergman A. Blum H. Cabo A. Di Stephani J. Grichnik A. Halpern R. Hofman-Wellenhof R. Johr H. Kittler A. Kopf J. Kreusch D. Langford J. Malvehy A. Marghoob S. Menzies F. Ozdemir K. Peris D. Piccolo M.A. Pizzichetta D. Polsky S. Puig H. Rabinovitz P. Rubegni T. Saida M. Scalvenzi S. Seidenari H.P. Soyer M. Tanaka I. Zalaudek R.P. Braun

Extracorporeal photochemotherapy induces apoptosis of infiltrating lymphoid cells in patients with mycosis fungoides in early stages. A quantitative histological study

Extracorporeal photochemotherapy (ExP) is a well‐tolerated new form of chemoimmunotherapy, which is considered to be effective for cutaneous T‐cell lymphoma (CTCL) and the treatment of choice for Sézary syndrome. Improvements have also been seen in patients with non‐erythrodermic mycosis fungoides (MF) in the early stages, even when tumour cells are not detectable in the peripheral blood. In this study, we used ExP as a monotherapy in seven patients who had early stage (Ib) MF, and who were no longer responsive to or had contraindications for other therapies. We observed a clinical improvement in the disease after 12 months of treatment: one patient showed a complete response, five a partial response, and one remained stable. In each patient we compared skin biopsies of large plaque lesions before and after the treatment. We undertook a histological evaluation of the infiltrate. The lymphoid cell proliferation and death rates were quantified using the following parameters: lymphoid cell density (LCD), Ki67+ lymphoid cell nuclei percentage (Ki67+ Lcn percentage), and apoptotic index (AI). Significant decreases in the lymphoid cell infiltrate and in cell proliferation, and a significant increase in AI were observed after therapy. The mean LCD decreased from 187 ± 33 to 34 ± 17·7, Ki67+ Lcn mean percentage decreased from 16·9 ± 3·9 to 4·9 ± 2·4, and the AI mean value increased from 0·05 ± 0·03 to 2·41 ± 1·54. Our results suggest a role for apoptosis in the improvement of the skin lesions and are in line with some reports on the mode of action of ExP. Although the way in which ExP works needs to be clarified further, it does seem to stimulate a CD8+ cell‐mediated anticlonotypic activity against circulating pathogenic clones. Furthermore, a release of tumour necrosis factor α (TNF‐α) by circulating monocytes has been demonstrated after ExP. Both are known to induce cell death by apoptosis.