Biomedical subjects

Riccardo Bono

Publications and source records attributed to Riccardo Bono.

5 recordsLinked to original sources

PubMed2007

Dermoscopic features of difficult melanoma.

BACKGROUND: The dermoscopic diagnosis of cutaneous melanoma (CM) may be difficult because some CM lack specific dermoscopic features for melanoma diagnosis. OBJECTIVE: To evaluate whether a diagnosis of CM could be achieved using the classic dermoscopic melanoma-specific criteria, we conducted a retrospective multicenter study of 508 CM samples. METHODS: All the dermoscopic images were analyzed to identify the dermoscopic criteria found in dermoscopically difficult melanomas (DDM) and to examine the possible relation of dermoscopic diagnosis with respect to the difficulty of the dermoscopic diagnosis and the melanoma thickness. RESULTS: A significant percentage of melanomas, 89 of 508 (17.5%), were DDM. The criteria leading to a significant increased risk of DDM were presence of streaks [odds ratio (OR), 2.26; 95% confidence interval (CI), 1.15-4.47), absence or presence of regular pigmentation (OR, 3.41; 95% CI, 1.70-6.85), absence of a blue-whitish veil (OR, 4.04; 95% CI, 2.33-6.99), absence of regression structures (OR, 4.31; 95% CI, 2.42-7.66), and the presence of hypopigmentation (OR, 2.61; 95% CI, 1.49-4.58). CONCLUSION: A significant number of melanomas defy even dermoscopic diagnosis. Only a meticulous comparative and interactive process based on an assessment of all the individual's other nevi ("ugly ducking" sign) and a knowledge about recent changes can lead to the recognition of DDM.

Adult↗

PubMed2004

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 391 melanomas 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.

Diagnosis, Computer-Assisted↗

PubMed2004

Dermoscopic patterns of cutaneous melanoma metastases.

Although the long experience acquired with the widespread use of dermoscopy has allowed the establishment of criteria for the recognition of benign and malignant skin lesions, very few data are available on cutaneous melanoma metastases. As the characteristic clinical aspects are multiform and even histological evaluation may sometimes be difficult, we have studied and characterized the patterns of cutaneous melanoma metastases in dermoscopy. In this paper, we report dermoscopic data on 130 histologically confirmed metastases observed in 32 patients affected by melanoma, with particular emphasis on dermoscopic features. Nine dermoscopic elements (homogeneous, saccular, amelanotic, polymorphic and vascular patterns, colour, perilesional erythema, pigmentary halo, peripheral grey spots) were studied in 130 cutaneous melanoma metastases and compared with those of 350 melanomas, 150 common naevi, 40 blue naevi, 40 haemangiomas and 50 basal cell carcinomas. The saccular and vascular patterns (especially polymorphic atypical vessels and winding vessels), as well as pigmentary halo and peripheral grey spots, seem to be the most significant elements suggestive of cutaneous melanoma metastases. The interest in and importance of the dermoscopic aspects of cutaneous melanoma metastases cannot be neglected if the American Joint Committee has determined that microsatellitosis and micrometastases are fundamental in the new TNM staging classification for cutaneous melanoma.

Adult↗

PubMed2004

Inter- and intra-variability of pigmented skin lesions: could the ABCD rule be influenced by host characteristics?

BACKGROUND/PURPOSE: Many differences in color, shape and dimension exist between different moles even in the same individual. Major differences might be accounted for anatomical location, genetic factors and by environmental factors, mainly sunlight exposure. Therefore, it would be of great value, when evaluating skin lesions, to take into account the degree of intra- and inter-variability of several diagnostic parameters. In order to assess the morphologic and chromatic differences between lesions belonging to different patients and between lesions belonging to the same individual, we examined objective digital parameters obtained with dermatoscopic analysis, using the DBDermo MIPS system (BIO MIPS Engineering, S.R.L, siena, Italy). METHODS: The automatic classifier inside the software is based on a 'match by similarity' algorithm, based on the measurement of the Euclidean distances of all variables considered from the reference image. Two-hundred and four clinically benign pigmented lesion, belonging to 18 patients were examined, stored and automatically processed. For each lesion objective parameters related to geometry, color and texture were automatically evaluated. RESULTS: We found skin color (healthy skin) is objectively different from subject to subject and the lesion color is more similar among different lesions of the same patient than among lesions belonging to different individuals both in their darkest and slightly dark component. We also observed that lesion dimensions are individual correlates, i.e. the probability for a lesion to be large is higher when the other, in the same patient, is large. CONCLUSION: Many parameters of pigmented skin lesions evaluated by digital dermoscopy analysis are similar in the same patient and different from those belonging to different individuals. This indicates that, when considering a lesion, we should take into account the peculiar patient's characteristics.

Diagnosis, Computer-Assisted↗

PubMed2003

Early diagnosis of malignant melanoma: Proposal of a working formulation for the management of cutaneous pigmented lesions from the Melanoma Cooperative Group.

Epiluminescence microscopy (ELM) strongly improves the separation of different types of cutaneous pigmented lesions (CPL) and facilitates the early diagnosis of cutaneous melanoma (CM). ELM alone is not 100% accurate in routine diagnosis, and should not be considered the only criterion in the diagnosis of high-risk skin lesions. We have however, demonstrated close agreement between ELM classification criteria and histology in 2,731 cutaneous lesions. In the past five years, our Melanoma Cooperative Group has evaluated 61,000 skin lesions from 30,000 individuals and identified 478 cutaneous melanomas. Most newly diagnosed patients had very early stage melanoma [299 (62%) were Stage I (203 Stage IA and 96 Stage IB), by the American Joint Committee on Cancer (AJCC) criteria]. We have compared data from the patient histories and clinical evaluations with ELM-based morphological patterns to better characterize skin lesions and minimize interpretative problems. From these comparisons, we propose new guidelines for the management of CPL to provide a standard diagnostic and therapeutic approaches and to foster the early identification of lesions at risk for malignant transformation.

Adolescent↗