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PubMed2003

[Correlation between dermoscopy and histopathology in pigmented and non-pigmented skin tumours].

Dermoscopy (dermatoscopy, epiluminescence microscopy, surface microscopy) is a non-invasive method in dermatology. With this method pigmented and non-pigmented skin tumours can be diagnosed with a clear higher sensitivity and specificity compared to clinical examination. Malignant skin tumours are detected earlier and unnecessary excisions of benign skin tumours can be avoided. The knowledge about the correlation between dermoscopy and histopathology is hereby an essential condition. In this continuing medical education article the correlation of both examination techniques is presented for the dermoscopic differential diagnoses.

Basal Cell Carcinoma↗
PubMed1993

Statistical evaluation of epiluminescence microscopy criteria for melanocytic pigmented skin lesions.

BACKGROUND: Epiluminescence microscopy (ELM) is a noninvasive technique by which the clinical diagnosis of pigmented skin lesions (PSL) can be improved. Many ELM criteria have been described, but their significance in the differential diagnosis of PSL has not yet been established. OBJECTIVE: The purpose of this study was to determine the value of ELM criteria in the differential diagnosis of PSL. METHODS: Two hundred one melanocytic PSL (61 common nevi, 60 dysplastic nevi, and 80 melanomas) were investigated with ELM for the presence of certain ELM criteria; their significance was determined by calculating the odds ratios. RESULTS: Individual ELM criteria have different weights of significance in the differential diagnosis of melanocytic PSL. Selected patterns of ELM criteria adjusted to the distinct types of PSL considerably improve the diagnostic accuracy of melanocytic PSL. CONCLUSION: The prevalence of certain distinct ELM criteria in a given melanocytic PSL has statistical value in differential diagnosis.

Confidence Intervals↗
PubMed1988

Cyclical Cushing's syndrome presenting as short stature in a boy with recurrent atrial myxomas and freckled skin pigmentation.

A young male patient demonstrated unusual features of Cushing's syndrome, atrial myxomas and freckled skin pigmentation. At 4.5 years of age he presented with intermittent swelling of his face and abdomen associated with weight gain and mild hypertension. A left atrial myxoma, suspected from routine physical examination, was surgically removed at 6.1 years of age. The initial mild symptoms clinically thought to be due to Cushing's syndrome, persisted intermittently without any consistent biochemical abnormality. At 10 years of age height velocity decreased and at 12 years early osteoporosis was observed radiologically. Repeated dexamethasone tests revealed a paradoxical increase in cortisol and corticotrophin from normal basal levels. Further investigation showed a cyclical pattern of hypercortisolism. The removal of a pituitary microadenoma failed to correct the features of Cushing's syndrome or prevent intermittent hypercortisolism. At 15.3 years a second left atrial myxoma was removed. This was followed by bilateral adrenalectomy. Histologically the features were consistent with primary pigmented nodular adrenocortical disease. This is the first patient described with cyclical Cushing's syndrome as part of this unusual complex of disorders.

Child, Preschool↗
PubMed2005

Inhibition of skin pigmentation by an extract of Lepidium apetalum and its possible implication in IL-6 mediated signaling.

The development of effective skin-lightening agents is an increasingly important area of research aimed at the treatment of hyperpigmentation induced by UV irradiation or by medical conditions such as melasma, postinflammatory melanoderma and solar lentigo. Although some inhibit tyrosinase, identifying and understanding the mechanisms of action of other agents is an important goal if more effective pigmentation inhibitors are to be developed. We present here that an extract of Lepidium apetalum (ELA) decreased UV-induced skin pigmentation in brown guinea pigs and melanogenesis of HM3KO human melanoma cells. Interestingly, ELA did not reduce melanogenesis in HM3KO cells unless they were co-cultivated in keratinocyte-conditioned medium prepared by culturing keratinocytes with ELA. Under these conditions, ELA decreased tyrosinase mRNA and protein expression as well as melanin content via an ELA-mediated increase in keratinocyte IL-6 production which in turn was shown to decrease in the expression Mitf, a transcription factor implicated in tyrosinase gene expression and melanocyte differentiation. The results reveal that ELA may be an effective inhibitor of hyperpigmentation caused by UV irradiation or by pigmented skin disorders through a mechanism involving IL-6-mediated downregulation of Mitf rather than a direct inhibition of tyrosinase activity.

Animals↗
PubMed1986

Ataxia telangiectasia with generalized skin pigmentation and early death.

A female infant with clinical and laboratory features of ataxia telangiectasia (AT) showed two clinical features exceptional for the disease, i.e. generalized skin pigmentation and an unusually early death at the age of 15 months. Her clinical features supportive of the diagnosis of AT included growth and developmental retardation and muscle weakness. Findings indicating immunodeficiency included recurrent pulmonary infections, failure of PHA stimulation of PB lymphocytes, decreased levels of serum IgM and IgA and on autopsy, an atrophic thymus without Hassall's corpuscles. Her cultured skin fibroblasts showed increased spontaneous chromosome breakages and hypersensitivity to X-ray irradiation, as would be expected for AT fibroblasts. She showed elevated blood HbF levels, macrocytic anaemia, granulocytopenia and thrombocytopenia, findings suggestive of a preleukaemic or leukaemic process. Yet aspirates of her bone marrow revealed no malignant cells. Autopsy revealed bilateral Pneumocystis carinii pneumonia, telangiectatic lesions in all the internal organs studied, sparse and degenerative Purkinje cells in the cerebellar cortex and atrophic ovaries. In view of these findings, it was concluded that the patient had a hitherto undescribed variant of ataxia telangiectasia.

Ataxia Telangiectasia↗
PubMed2003

From colour to tissue histology: Physics-based interpretation of images of pigmented skin lesions.

Through an understanding of the image formation process, diagnostically important facts about the internal structure and composition of pigmented skin lesions can be derived from their colour images. A physics-based model of tissue colouration provides a cross-reference between image colours and the underlying histological parameters. It is constructed by computing the spectral composition of light remitted from the skin given parameters specifying its structure and optical properties. The model is representative of all the normal human skin colours, irrespective of racial origin, age or gender. Abnormal skin colours do not conform to this model and thus can be detected. Once the model is constructed, for each pixel in a colour image its histological parameters are computed from the model. Represented as images, these 'parametric maps' show the concentration of dermal and epidermal melanin, blood and collagen thickness across the imaged skin as well as locations where abnormal colouration exists. In a clinical study the parametric maps were used by a clinician to detect the presence of malignant melanoma in a set of 348 pigmented lesions imaged using a commercial device, the SIAscope. Logistic regression identified the presence of melanin in the dermis, the abnormal distribution of blood within the lesion and the lesion size as the most diagnostically informative features. Classification based on these features showed 80.1% sensitivity and 82.7% specificity in melanoma detection.

Colorimetry↗
PubMed2003

High-frequency sonography and color Doppler in the management of pigmented skin lesions.

We aimed to evaluate high-frequency sonography (HFS) coupled with color Doppler in the management of pigmented skin lesions (PSL). HFS examination was performed in 111 patients with 130 PSL. A color Doppler study was conducted in 107 lesions, to assess intralesional vascularization. Imaging findings were compared with histologic diagnosis. In the case of melanoma, sonographic and histologic maximum thickness measurements were compared. HFS showed 114 of the 130 lesions. Among the detected lesions, HFS alone provided 100% sensitivity and 100% specificity in the distinction of melanoma/nevi from other lesions, and 100% sensitivity and 32% specificity in the distinction of melanomas from nonmelanoma lesions. Sonographic and histologic measurement of melanoma thickness strongly correlated (r > 0.96, p < 0.001). Color Doppler detection of intralesional vessels had a 100% specificity and 34% sensitivity in the distinction of melanomas from other PSL. HFS coupled with color Doppler is a simple, reliable tool for PSL management.

Adolescent↗
PubMed1986

X-linked short stature with skin pigmentation: evidence for heterogeneity of the Russell-Silver syndrome.

A family is described with a syndrome of short stature, abnormal pigmentation of the skin and mild facial dysmorphism. The short stature and pigmentary anomalies were more marked in the males than the females. The pattern of inheritance appeared X-linked. In 2 young brothers the clinical picture mimicked that of the Russell-Silver syndrome. It is suggested that the Russell-Silver syndrome is heterogeneous and that the criteria for its diagnosis need re-evaluation.

Adult↗
PubMed2004

"Constitutive" skin pigmentation: a marker of breast cancer risk?

There is much evidence to support a link between oestrogen and breast cancer. Both adult and foetal oestrogen may have this predisposing effect, and between-individual and between-population differences in oestrogen may account for much of the variation in risk for breast cancer. Here we suggest that "constitutive" skin colour in women is a marker for prenatal and adult oestrogen levels such that within ethnic groups light-skinned women have experienced higher in utero and adult oestrogen than dark-skinned women. Scores for 'constitutive' skin pigment may therefore be predictive of risk for breast cancer and low scores could be used to identify individuals at high risk.

Biomarkers, Tumor↗
PubMed1990

Skin pigmentation from clofazimine therapy in leprosy patients: a reappraisal.

Skin biopsy specimens from two lepromatous leprosy patients with dark brown pigmentation who were receiving long-term clofazimine therapy were studied. Ceroid-lipofuscin pigment was demonstrated inside macrophages that contained numerous phagolysosomes. These contained lipids and clofazimine that appeared as electron-lucent vacuoles and a lipofuscin pigment that was electron dense, granular, and lamellated. Although the presence of the drug in tissues contributed to the skin pigmentation, the main cause was a drug-induced, reversible ceroid lipofuscinosis.

Aged↗
PubMed2002

Dermoscopic diagnosis by a trained clinician vs. a clinician with minimal dermoscopy training vs. computer-aided diagnosis of 341 pigmented skin lesions: a comparative study.

BACKGROUND: In the last few years digital dermoscopy has been introduced as an additional tool to improve the clinical diagnosis of pigmented skin lesions. OBJECTIVE: To evaluate the validity of digital dermoscopy by comparing the diagnoses of a dermatologist experienced in dermoscopy (5 years of experience) with those of a clinician with minimal training in this field, and then comparing these results with those obtained using computer-aided diagnoses. METHODS: Three hundred and forty-one pigmented melanocytic and non-melanocytic skin lesions were included. All lesions were surgically excised and histopathologically examined. Digital dermoscopic images of all lesions were framed and analysed using software based on a trained artificial neural network. Cohen's kappa statistic was calculated to assess the validity with regard to the correct diagnoses of melanoma and non-melanoma. RESULTS: Sensitivity was high for the experienced dermatologist and the computer (92%) and lower for the inexperienced clinician (69%). Specificity of the diagnosis by the experienced dermatologist was higher (99%) than that of the inexperienced clinician (94%) and the computer assessment (74%). Notably, computer analysis gave a higher number of false positives (26%) compared with the experienced dermatologist (0.6%) and the inexperienced clinician (5.5%). CONCLUSIONS: Our results indicate that analysis either by a trained dermatologist or an artificial neural network-trained computer can improve the diagnostic accuracy of melanoma compared with that of an inexperienced clinician and that the computer diagnosis might represent a useful tool for the screening of melanoma, particularly at centres not experienced in dermoscopy.

Adolescent↗
PubMed1990

An investigation of factors affecting the accuracy of in vivo measurements of skin pigments by reflectance spectrophotometry.

Factors affecting the accuracy of the in vivo measurement of cutaneous pigments and blood oxygenation by reflectance spectrophotometry have been examined. It was found that stray light, the amounts of haemoglobin and melanin, and the level of blood oxygenation all contributed to the measured reflectance and had to be taken into account when calculating quantitative indices of skin pigments. Measurements on isolated sheets of epidermis demonstrated that over 50% of normally incident radiation is transmitted in a forward direction within 17 degrees of the incident direction and approximately 20% is backscattered between 90 degrees and 180 degrees out of the sample, approximately 6.0% of it by specular reflection at the surface. The effective optical pathlength in suspensions of whole red cells was found to be 7% greater than in simple solutions containing the same concentration of haemoglobin.

Hemoglobins↗
PubMed2006

Hypoepiluminescence microscopy of pigmented skin lesions: new approach to improve recognition of dermoscopic structures.

BACKGROUND: Hypoepiluminescence microscopy (HELM) is a new dermoscopic approach for analysis of pigmented skin lesions (PSLs) after surgical excision. OBJECTIVES: The objective was to verify whether this method could provide additional morphologic information for diagnostic or didactic purposes compared to conventional epiluminescence microscopy (ELM). PATIENTS AND METHODS: Thirty-one PSLs from 30 patients were consecutively evaluated by ELM and, after excision, by HELM. For HELM examination, the lesion was positioned on a glass slide and illuminated from above with a halogen lamp and from underneath with an LED source. All lesions were subsequently examined histopathologically. RESULTS: In 11 of 31 (35.5%) lesions, a typical pigment network, as assessed by ELM, appeared bidimensional with HELM. In 9 lesions (9/31; 29%) ELM showed a gray-blue area, while HELM allowed us to distinguish 5 lesions (5/9, 55.5%) with gray area predominant showing a lichenoid lymphocytic infiltration and few melanophages from the other 4 lesions (4/9, 44,5%) with heavy dermal accumulation of pigmented melanocytes or melanophages where a blue area was clearly visible at HELM. In 9 other cases (29%), ELM analysis revealed a central homogeneous dark brown/black pigmentation that in 7 cases was seen under HELM examination to consist of globules. CONCLUSIONS: HELM is particularly useful in evaluating heavily PSLs or structures located in the reticular dermis.

Adolescent↗
PubMed1997

Dermoscopy (epiluminescence microscopy) of pigmented skin lesions. Current status and evolving trends.

Dermoscopy (epiluminescence microscopy) is a noninvasive technique that is designed for in vivo microscopic examination of pigmented skin lesions, particularly for the early recognition of malignant melanoma. Since its introduction, dermoscopy technique has undergone extensive improvements; the instruments have become more readily available; and the diagnostic indications, benefits, and limitations have been better delineated. This article offers a concise review of the technique of dermoscopy, assesses the current status, and makes some predictions for future applications.

Diagnosis, Differential↗
PubMed2006

Comments on "A new algorithm for border description of polarized light surface microscopic images of pigmented skin lesions".

In this paper, discrepancies and reference inaccuracies in the paper (Grana et al., 2003) are pointed out. Specifically, it is demonstrated that the definitions of "lesion gradient" and "skin lesion gradient," widely used in a number of medical papers on computer analysis of pigmented skin lesions, are unambiguous, and that the "new algorithm for border description" described in the subject paper substantially relies on well-established concepts dating back over one decade ago.

Algorithms↗
PubMed2003

Principles of dermatoscopy of pigmented skin lesions.

There has been a dramatic increase in the incidence of malignant melanoma in most parts of the world. Because the tumor thickness is the most important prognostic factor for the prognosis of the malignant melanoma, the early detection of thin melanomas is essential. Dermatoscopy allows the physician to discriminate between melanocytic and nonmelanocytic lesions with high diagnostic accuracy and to detect initial malignant melanomas. We review the principles of dermatoscopy and the differential diagnosis of pigmented skin lesions. Before using the ABCD rule of dermatoscopy to classify melanocytic lesions into benign, suspicious, or malignant, the distinction between melanocytic and nonmelanocytic lesions is necessary. An essential prerequisite for the usefulness of this technique is adequate training.

Dermatology↗
PubMed1989

Genetic evidence for linkage with the Z and W sex chromosomes of two distinct couples of alleles controlling larval and postmetamorphic skin pigmentation in salamander.

In Pleurodeles waltl, progeny resulting from a cross between 2 individuals of the Z/W sexual genotype include 25% of W/W individuals, while those issued from crossing a Z/W neomale with a W/W thelygenous female include 50% of W/W individuals. W/W individuals can be identified through the peptidase-1 zymogram since, in P. waltl, this enzyme is controlled by codominant alleles which are linked to the sex chromosomes. In such progeny, we discovered 2 mutant phenotypes affecting larval and postmetamorphic skin pigmentation in W/W individuals. These phenotypes are described herein. The study of their inheritance in several offspring provides evidence that they are controlled by 2 distinct genes, the recessive mutant alleles of which are linked to the W sex chromosome; moreover, in thelygenous W/W females, the differential segment does not prevent the occurrence of meiotic recombinations between W sex chromosomes. Mutant skin pigmentary phenotypes are easily identified and constitute a tool for rapid, efficient selection of individuals of the W/W sexual genotype.

Alleles↗