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At least 253 records · Page 14Linked to original sources
PubMed2000

Septo-optic dysplasia in combination with a pigmented skin lesion: a case report with nosological discussion.

In this case report a patient with bilateral optic nerve hypoplasia, schizencephaly and a pigmented skin lesion is described. The diagnosis of de Morsier syndrome or septo-optic dysplasia is put forward on the basis of the diagnosis of optic nerve hypoplasia. The differential diagnosis with Jadassohn's naevus phakomatosis is discussed. The importance of direct ophthalmoscopy of optic nerve abnormalities is stressed, as well as of magnetic resonance imaging, which has become a guideline in the classification of this syndrome.

Brain↗
PubMed1997

Measurement of lip and skin pigmentation using reflectance spectrophotometry.

Previous methods for evaluating the color of oral epithelial tissues have relied primarily on subjective indices and interpretation. In this study, a narrow-band reflectance spectrophotometer was used to measure melanin and hemoglobin pigmentation in the lips and skin of individuals who self-reported their skin type from a choice of white, olive, or black. Significant differences in melanin pigmentation were observed among skin types and at most anatomical sites evaluated between skin types. Hemoglobin levels were not significantly different among skin types at most anatomical sites, but differences were observed among anatomical sites within each skin color group. Within each skin type, melanin (except in blacks) and hemoglobin were significantly higher for both the upper and lower lips compared with most other anatomical sites. Results suggest that reflectance spectrophotometry is a useful tool for quantifying differences in melanin and hemoglobin pigmentation in oral tissues.

Analysis of Variance↗
PubMed1997

Epiluminescence microscopy of small pigmented skin lesions: short-term formal training improves the diagnostic performance of dermatologists.

BACKGROUND: Epiluminescence microscopy (ELM) makes subsurface structures of the skin accessible for in vivo examination and provides additional criteria for the clinical diagnosis of pigmented skin lesions (PSLs). We demonstrated that ELM increases diagnostic sensitivity in dermatologists formally trained in the use of this technique but decreases diagnostic ability in dermatologists not formally trained in its application. OBJECTIVE: Our purpose was to determine the effects of short formal ELM training on the diagnostic performance of 11 previously untrained dermatologists. METHODS: One hundred image-pairs of randomly selected histologically proven PSLs, photographed with (ELM) and without oil immersion (surface microscopy), were presented by slide projection to the testees. To evaluate the effects on diagnostic performance before and after short-term training, we used the receiver-operator characteristics technique. RESULTS: Without training the use of ELM did not enhance diagnostic accuracy, but rather decreased it in 8 of 11 testees. In contrast, after 9 hours of formal training in ELM the diagnostic performance of the testees was significantly enhanced with an average gain of 8.4%. CONCLUSION: Our data confirm that formal training is required for the useful application of the ELM technique.

Austria↗
PubMed1996

The invisible colours of melanoma. A telespectrophotometric diagnostic approach on pigmented skin lesions.

Reflectance images of 43 pigmented lesions of the skin (18 melanomas, 17 common melanocytic naevi and eight dysplastic naevi) were acquired by a telespectrophotometric system and were analysed in the spectral range from 420 to 1040 nm, to discriminate melanoma from benign melanocytic entities. Different evaluations were carried out considering the whole spectrum, the visible and the near infra-red. A total of 33 (76.7%) lesions were correctly diagnosed by the telespectrophotometric system, compared with 35 (81.4%) correct clinical diagnoses. Reflectance in the infra-red band appears diagnostically relevant. A larger study is needed to prove the validity of this diagnostic method.

Diagnosis, Differential↗
PubMed2002

Modulation of microphthalmia-associated transcription factor gene expression alters skin pigmentation.

The microphthalmia-associated transcription factor is implicated in melanocyte development and in the regulation of melanogenesis. Microphthalmia-associated transcription factor is thought to bind to the M-box promoter elements of tyrosinase, tyrosinase-related protein-1 and dopachrome tautomerase/tyrosinase-related protein-2 and transactivate these genes, resulting in increased pigmentation. Using a luciferase reporter construct driven by the microphthalmia-associated transcription factor promoter, we identified agents that modulate microphthalmia-associated transcription factor promoter activity. Changes in endogenous microphthalmia-associated transcription factor expression levels upon treatment with these agents were confirmed using northern and western blots, and their pigmentary modulating activities were demonstrated. Ultraviolet B irradiation and traditional Chinese medicine-1, a natural extract used in traditional Chinese medicine, upregulated microphthalmia-associated transcription factor gene expression and enhanced tyrosinase activity in vitro. Dihydrolipoic acid, lipoic acid, and resveratrol reduced microphthalmia-associated transcription factor and tyrosinase promoter activities. These agents also inhibited the forskolin- and ultraviolet B-stimulated promoter activities of these genes and significantly reduced tyrosinase activity in melanocyte cultures, resulting in depigmentation. Overexpressed microphthalmia-associated transcription factor was capable of rescuing the repressive effects of these compounds on the cotransfected tyrosinase promoter. Dark-skinned Yucatan swine treated with these agents showed visible skin lightening, which was confirmed histologically, whereas ultraviolet B-induced tanning of light-skinned swine was inhibited using these agents. Our findings suggest that modulation of microphthalmia-associated transcription factor expression can alter skin pigmentation and further confirm the central role of microphthalmia-associated transcription factor in melanogenesis.

8,11,14-Eicosatrienoic Acid↗
PubMed1994

The distribution of cellular adhesion molecules in pigmented skin lesions.

BACKGROUND: The process of multistep tumor development has been studied thoroughly in the development of malignant melanomas. The authors investigated the expression of cellular adhesion molecules in nevomelanocytic lesions to explore a postulated role of adhesion molecules in cell-cell and cell-matrix interactions during tumor development. METHODS: Sections of 20 nevocellular nevi, 35 dysplastic nevi, 6 melanomas in situ, and 20 malignant melanomas were investigated with respect to their expression of intercellular adhesion molecule-1 (ICAM-1), inducible cell adhesion molecule-110 (INCAM-110)/vascular cell adhesion molecule-1 (VCAM-1), E-selectin, lymphocyte function-associated antigen-1 (LFA-1), and the integrins for very late antigen-(VLA) alpha-(alpha) 2 and VLA-alpha 6; for these studies, monoclonal antibodies were used and indirect immunoperoxidase and immunofluorescence staining methods were performed. RESULTS: In the transformation from benign to malignant neoplasms, the expression of ICAM-1 was upregulated strongly. The expression of VLA-alpha 2 on tumor cells increased whereas that of VLA-alpha 6 decreased; these alterations corresponded to changes previously observed in their ligands within the extracellular matrix. These results were statistically significant. In addition, ICAM-1, INCAM-110/VCAM-1, and E-selectin were detected in activated endothelial cells, probably as a result of cytokine activation. The ligand for ICAM-1, LFA-1, was confined to mononuclear cells. CONCLUSIONS: The increase in ICAM-1 and VLA-alpha 2 expression and the decrease of VLA-alpha 6 expression may, in combination with specific matrix alterations, lead to a change in cell-cell and cell-matrix interaction, thereby contributing to the invasive property of melanocytic tumor cells. The neoexpression of INCAM-110/VCAM-1 and E-selectin in pigmented skin lesions may play a role in both infiltrative growth and the generation of a host reaction toward these tumors.

Animals↗
PubMed2000

Differentiation of common benign pigmented skin lesions from melanoma by high-resolution ultrasound.

BACKGROUND: There are potential clinical benefits if non-invasive methods can be used to diagnose or exclude melanoma. OBJECTIVES: We investigated high-resolution ultrasound (HRU) as a potential non-invasive diagnostic aid for pigmented skin lesions. METHODS: Using a 20-MHz ultrasound B-scan imaging system interfaced to a computer, we assessed acoustic shadowing and entry echo line enhancement (EEE) for 29 basal cell papillomas (BCPs) and 25 melanomas. Acoustic shadowing was estimated by the dermal echogenicity ratio (DER), comparing mean echogenicity below the lesion with that of adjacent dermis. Histological features were scored independently. RESULTS: DER < 3 correctly distinguished melanoma from BCP with 100% sensitivity and 79% specificity. Specificity increased to 93% if the presence of EEE was included as a discriminator. Shadowing correlated most significantly with histological extent of hyperkeratosis (P < 0.0001). Consequently, this method falsely identified non-keratotic acanthotic BCP (n = 3) as melanoma. Highly significant differences between benign naevi (n = 15) and melanomas (n = 24) were found. The SD of retrolesional echogenicity was higher for naevi than melanomas (P < 0.0001), but such an analysis was poorly specific for the diagnosis of melanoma (30%). CONCLUSIONS: Overall, HRU has considerable potential as a high-performance screening tool to assist in the discrimination between BCP, but not benign naevi, and melanoma. In particular, it may be possible to exclude melanoma with 100% certainty in the differentiation of BCP from melanoma.

Diagnosis, Differential↗
PubMedDate not supplied

[Physiology of skin pigmentation].

The physiological colour of the skin is due, above all, to the presence of melanin in the dermis and the epidermis, but also to the presence of other pigments of endogenous or exogenous origin, such as iron and carotene. The authors present a study of melanogenesis. They review the structure of the eumelanins and the phaeomelanins and recall the steps in their biosynthesis. They examine the functioning of the epidermal unit of melanization, which is a functional unit consisting of a melanocyte, derived from the neural crest, and the keratinocytes which depend on it. The melanocyte synthetizes pigment granules, the melanosomes, which undergo maturation before being transferred and then broken down by the keratinocytes. Finally, the authors study the principal factors which influence the functioning of the epidermal unit of melanization : genetic control, ultra-violet radiation and endocrine factors.

Adult↗
PubMed1983

Solomon Islander skin pigmentation: ultrastructural differences related to genetic variation in Melanesia.

Genetic differences between Solomon Islander populations are distinguishable on the basis of melanosome packaging in epidermal keratinocytes. By electron microscopic study of skin pigmentation in various Melanesian populations, we have found distinct inter-island differences in the mode of melanosome packaging. Melanosomes are found as singlets in the skin of Bougainville Islanders but are found aggregated in melanosome complexes in Malaita Islanders and Ontong Javanese. This variation in melanosome packaging represents an important biologic difference found between Solomon Islanders and may reflect the genetic diversity existing in the original Melanesian founding population or the genetic diversity existing in the original Melanesian founding population or populations.

Genetic Variation↗
PubMed1996

Interobserver variability on the histopathologic diagnosis of cutaneous melanoma and other pigmented skin lesions.

PURPOSE: To assess the interobserver agreement on the diagnosis and classification of cutaneous melanoma. MATERIALS AND METHODS: A set of 140 slides of cutaneous melanoma, including a small subset of benign pigmented skin lesions, were circulated to four experienced histopathologists. The kappa statistic for multiple ratings per subject was calculated using the method described by Fleiss. RESULTS: The kappa value on the diagnosis of cutaneous melanoma versus benign lesions was 0.61. There was some discordance on the diagnosis in 37 of 140 cases (26%). For the histopathologic classification of cutaneous melanoma, the highest kappa values were attained for Breslow thickness (kappa = 0.76) and presence of ulceration (kappa = 0.87). The agreement was generally poor for other histologic features, such as level of dermal invasion (kappa = 0.38), presence of regression (kappa = 0.27), and lymphocytic infiltration (kappa = 0.27). CONCLUSION: Our study suggests considerable disagreement among pathologists on the diagnosis of melanoma versus other pigmented lesions. Tumor thickness and presence of ulceration are the most reproducible histologic features of cutaneous melanoma.

Humans↗
PubMed2001

Tissue- and urokinase-type plasminogen activators and type 1 plasminogen activator inhibitor in melanomas and benign skin pigment neoplasms.

The content of urokinase- and tissue-type plasminogen activators and plasminogen activator inhibitor PAI-1 in the cytosol of primary and metastatic melanomas and benign skin pigment neoplasms was estimated by enzyme immunoassay. It was shown that local growth and invasion of melanomas are related to suppressed expression of tissue plasminogen activator. The content of urokinase plasminogen activator increases in patients with distant metastases and large thickness of the primary tumor.

Adult↗
PubMed1983

[Increased information value of the radiophosphorus diagnosis of pigmented skin neoplasms].

A complex of new methods are proposed. They make it possible to improve the precision and informative value of the results of 32P diagnosis of pigmental skin tumors. The following methods are used: 1) fractional administration of the indicator to increase the level of 32P accumulation in melanomas; it made it possible to improve the differential-diagnostic capacity of the radiophosphorus test; 2) beta-radiometry of pathological and control skin zones with and without fine tissue equivalent filters to "contrast" tumors and to determine the average depth of their invasion to unchanged tissues; the use of this method made it possible to lessen the number of false-negative diagnoses and to get additional clinicodiagnostic information that can be useful in the planning of surgical and radiation treatment; 3) radiometry of skin zones in the spectrometric regimen with three different levels of the integral discrimination of beta-radiation impulses to determine the thickness and lower line of the layer of the abnormal accumulation of the indicator in the pathological skin zone; the use of this method makes it possible to detect incrusted melanomas.

Diagnosis, Differential↗
PubMed1995

The histological and immunohistochemical changes in the skin of patients with melanoma who develop changes in skin pigmentation following immunotherapy.

The histological and immunocytochemical appearances of skin with altered pigmentation from two patients receiving chemoimmunotherapy for melanoma were examined. In both patients, there was a clinical response to treatment coincident with depigmentation of skin and hair. Skin biopsies showed extensive infiltration with CD8+ and CD4+ lymphocytes rather than CD57+ in the depigmented areas suggestive of a specific MHC-related cytotoxic T-cell activity against melanocytes. In keeping with this, MHCII expression was markedly up-regulated. These observations suggest the development of a simultaneous anti-tumour and anti-melanocyte immune response stimulated by chemoimmunotherapy, possibly against the same or similar antigens.

Adult↗
PubMed1997

Risk assessment of side effects from copper vapor and argon laser treatment: the importance of skin pigmentation.

BACKGROUND AND OBJECTIVE: Epidermal melanin is a limiting factor for obtaining beneficial results in dermatological treatment of vascular malformations. The aim of our study was to predict the highest laser intensity and energy fluence which can be applied to skin with different degrees of pigmentation before side effects are induced. STUDY DESIGN/MATERIALS AND METHODS: Thirteen human volunteers with different degrees of skin pigmentation were laser-treated on the inside of the brachium with an argon laser (AL, 488 nm and 514.5 nm) and a copper vapor laser (CVL, 578 nm), both connected to a Hexascan. Three input intensities were used. 0.7, 1.0, and 1.3 W. Pulse duration was kept constant at 200 msec, resulting in hexascan fluences of 14.1, 20.2, and 26.2 J/cm2. At the 6-month assessment it was noted whether pigmentary changes or scarring were clinically absent or present. The results were analysed by logistic regression. RESULTS: We found that pretreatment pigmentation percentage and laser intensity were significant risk factors of inducing side effects (P < .001), whereas it was without significant importance whether the AL or the CVL was used (P > .05). Contour lines of 1, 2.5, 5, 10, 25, and 50% risk levels of inducing clinically recognizable pigmentary changes and scarring were calculated. Pigmentary changes occurred at a significantly lower intensity level than skin texture changes (P = .006). CONCLUSION: On basis of our results, we recommend assessment of skin pigmentation prior to laser treatment with the CVL and the AL, and we recommend that the illustrated risk levels are taken into consideration.

Adult↗
PubMed1988

Are malignant melanoma time trends explained by changes in histopathological criteria for classifying pigmented skin lesions?

The incidence of malignant melanoma in developed countries has been rising rapidly in recent years. Its causes and the reasons for this trend are uncertain. Changes in histopathological criteria for classifying pigmented skin lesions could explain the rising incidence rates. With support from the International Agency for Research on Cancer, this hypothesis is explored but not substantiated for time trends in the South Western Region, United Kingdom.

England↗
PubMed1997

Examination of the ability of people to identify early changes of melanoma in computer-altered pigmented skin lesions.

OBJECTIVES: To examine whether older people were less able to distinguish changes of melanoma than younger people, and to test whether an educational brochure illustrating changes of melanoma would increase their ability to detect the changes. DESIGN: Photographic images of pigmented skin lesions were altered using computer graphics software. Images of typical changes of melanoma were shown to groups of volunteers younger than 30 years (n = 52) and older than 45 years (n = 41). Short intervals (seconds) between viewing of the original and changed lesions were used to test ability to distinguish the changes, and longer intervals (29 and 60 days) were used to test their ability over more realistic intervals. All participants were randomized to receive an educational brochure (designed using the same technology) to evaluate whether this would assist in identifying early changes of melanoma. SETTING: A cross section of volunteers employed in a large semigovernment utility. INTERVENTION: An educational brochure that illustrated typical changes of melanoma. MAIN OUTCOME MEASURE: Score of correct or incorrect detection of changed or unchanged skin lesions. RESULTS: Tests at short intervals showed that both age groups were able to detect early changes of melanoma but had poor ability to detect changes of melanoma at longer intervals. Repeated viewing of the original lesions enabled the participants to once more recognize the changes. Both groups had low ability to detect the appearance of new pigmented lesions. The educational brochure improved the ability of participants to detect change. CONCLUSIONS: The main difficulty people have in self-detection of melanoma is limited ability to recall the appearance of their skin. This ability did not differ between the age groups. Educational material that focused on change was effective in increasing the ability to detect changes over short intervals. Photographic records may be the most effective aid for detection of changes at longer intervals.

Adult↗