Library

Notes: The association of two different neoplasms in the same lesion is uncommon and has been reported as collision or compound tumours in the medical literature. In cases where a malignant neoplasm exists in association with a benign lesion it is important to make an accurate diagnosis in order to treat the lesions correctly. Dermoscopy is an in vivo, noninvasive technique that improves the clinical accuracy in diagnosing melanoma and other pigmented skin lesions. We describe the dermoscopic characteristics of various collision or compound tumours that were composed of benign and malignant neoplasms: two cases of seborrhoeic keratosis associated with basal cell carcinoma, two cases of melanocytic naevus and basal cell carcinoma and one case of dermatofibroma associated with basal cell carcinoma. We conclude that dermoscopy is a useful tool for improving the recognition of these kinds of tumours.

Notes: Background  Dermoscopy improves the diagnostic accuracy in pigmented skin lesions, but it is also useful in the evaluation of nonpigmented skin tumours as it allows the recognition of vascular structures that are not visible to the naked eye. Bowen's disease (BD) or squamous cell carcinoma in situ is usually nonpigmented, but may also rarely be pigmented.Objective  To describe the dermoscopic features in a series of pigmented and nonpigmented BD.Methods  Dermoscopic images of 21 histopathologically proven BD were evaluated for the presence of various dermoscopic features. Each lesion was photographed using the Dermaphot (Heine Optotechnik, Herrsching, Germany), at 10-fold magnification, and the colour slides were scanned to digital format using a Kodak Photo CD system.Results  The majority of cases of BD revealed a peculiar dermoscopic pattern characterized by glomerular vessels (90%) and a scaly surface (90%). In addition, in pigmented BD small brown globules regularly packed in a patchy distribution (90%), and structureless grey to brown pigmentation (80%) were observed.Conclusions  Dermoscopy can be helpful for diagnosing BD because of the presence of repetitive morphological findings such as glomerular vessels and a scaly surface. In pigmented BD, small brown globules and/or homogeneous pigmentation can be seen as well.

Notes: Background  Xeroderma pigmentosum (XP) is a rare disorder produced by a genetic defect in the repair of DNA damage caused by ultraviolet radiation. The early diagnosis of malignant skin tumours is crucial in the survival of patients with XP, but this is not easy even for experienced dermatologists due to the presence of a high number of actinic lesions. Dermoscopy is a new diagnostic method that increases the diagnostic accuracy for skin tumours.Objectives  To describe the clinical and dermoscopic features of different benign and malignant lesions [focusing on malignant melanoma, basal cell carcinoma (BCC) and benign melanocytic naevi] in two patients with XP.Methods  Three dermatologists with experience in pigmented skin lesions and dermoscopy examined two siblings with XP over a period of 54 months. Diagnosis of skin tumours was obtained using clinical examination and dermoscopy with 10-fold magnification and digital images. All the tumours with criteria of malignancy were excised for further histopathological analyses.Results  Multiple skin tumours showing some degree of pigmentation were detected in the patients. Clinical and dermoscopic examination allowed the discrimination of four melanomas (three of them in situ), 26 BCCs and five dysplastic naevi from other pigmented skin lesions. The features and parameters previously described for dermoscopy were shown to be appropriate for the recognition of tumours in our patients with XP. Generalized actinic lentigos were distinguished from BCCs by the presence of a delicate brown pigmented network. Fine vessels from poikiloderma were differentiated from the arborizing telangiectasia of BCC.Conclusions  The dermoscopic findings in the tumours were similar to those previously described in patients not affected by XP. Diagnosis by dermoscopic pattern analyses allowed a correct classification of malignant tumours in these cases.

Notes: Background  Benign melanocytic skin lesions may be difficult to differentiate from melanoma both clinically and dermoscopically. One of the most confounding dermoscopic features, commonly seen in melanoma but in our experience also in melanocytic naevi, is represented by the so-called blue–white structures (BWS).Objectives  To evaluate diagnostic significance and histopathological correlates of BWS seen by dermoscopy in a series of clinically equivocal melanocytic skin lesions that were excised.Methods  Patients were recruited from six specialized pigmented lesion clinics in Austria, Italy and Spain over a period of 9 months. All consecutive patients showing one or more melanocytic lesions with BWS, but not classified as melanoma dermoscopically, were included. Each lesion was photographed clinically and dermoscopically. All images were reviewed by one of us and the degree, type and location of BWS evaluated for each lesion. A panel of four experienced dermatopathologists independently reviewed all specimens for diagnosis and one of them evaluated presence and degree of melanosis and/or fibrosis. The main outcome measures were the percentage and histopathological correlates of lesions with different degree, type and location of BWS.Results  All included lesions with BWS (n = 158) showed partial or focal regression histopathologically. One hundred and thirty-five (85·4%) lesions were diagnosed as melanocytic naevi (complete histopathological interobserver agreement), whereas 23 (14·6%) were defined as equivocal because at least one of four pathologists diagnosed the given lesion as melanoma. Only one lesion was diagnosed as melanoma by all four pathologists. The majority of naevi exhibited blue areas (84·4%) with a central distribution (57%) and involving 〈 50% of the lesion surface (89·6%). By contrast, 78·3% of equivocal lesions revealed a combination of white and blue areas with an irregular distribution (60·9%) and involving 〉 50% of the lesion surface (47·8%).Conclusions  Using degree and type of BWS, an algorithm was constructed that can be applied for the management of lesions exhibiting dermoscopic features of regression.