The Eumelanin Human Skin Colour Scale: a proof-of-concept study.

BACKGROUND: At present there is no standard nomenclature for describing the diversity of human constitutive skin colour. OBJECTIVES: To develop a standard nomenclature to describe human constitutive skin colour. METHODS: Monthly focus group discussions were carried out among a multidisciplinary group of specialists over a 7-month period. Topics covered were (i) limitations and unmet needs of current nomenclature(s) pertaining to human cutaneous diversity, (ii) practical considerations about the function and role of any proposed nomenclature pertaining to human cutaneous diversity, (iii) review of the cellular basis and current molecular genetic understanding of variation in human skin pigmentation and (iv) in vivo methods to evaluate human skin pigmentation. In addition, a preliminary review of the published literature was undertaken to collate data on published skin reflectance measurements, notably melanin index values for well-referenced human populations. RESULTS: We developed a five-point scale to describe the full spectrum of human constitutive skin colour, termed the Eumelanin Human Skin Colour Scale. The nomenclature of the scale uses eumelanin, the dominant chromophore of human skin, as a central descriptive word. The categories of the scale (nomenclature and melanin index values) are eumelanin low (EML), < 25; eumelanin intermediate low (EMIL), 25 to < 50; eumelanin intermediate (EMI), 50 to < 75; eumelanin intermediate high (EMIH), 75 to < 100; and eumelanin high (EH), ≥ 100. CONCLUSIONS: The Eumelanin Human Skin Colour Scale enables the complete range of human constitutive skin colour to be described in an objective, equitable and understandable manner. In future, this scale can be used as the basis for developing other scales that address the specific functional aspects of human skin, such as response to ultraviolet radiation.

Molecular diagnostics-an emerging frontier in dermatopathology.

Advances made within the field of genomics and proteomics have facilitated the emergence of a new era of molecular diagnostics. However, ongoing rapid developments in molecular methodology ensure that this remains a complex field, accessible primarily to scientists who routinely utilize these techniques. For this reason, in this article we provide a concise overview of established and emerging molecular methods and discuss their role as diagnostic adjuncts in Dermatopathology. Important nonmolecular techniques that are used in conjunction with molecular methods are also highlighted.

Incidental microscopic foci of nevic aggregates in skin.

Microscopic foci of nevic aggregates have been described in normal lymph nodes, where they may pose diagnostic challenges to pathologists. In the course of our practice, we have observed a similar phenomenon in cutaneous tissue. For this reason, we performed a retrospective study of cutaneous excisions over a 1-year period to better characterize this observation. We reviewed 2482 pathology reports of cutaneous excisions, of which 0.8% were associated with such microscopic foci of incidental nevic aggregates. Incidental nevic aggregates were typically dermal in nature and found commonly in excisions from the head and neck region. They were clinically unapparent, with a maximum mean horizontal and vertical diameter of 0.86 mm (0.3-1.5 mm) by 0.46 mm (0.1-1.3 mm). The nevic aggregates were separate and located in normal skin, away from any associated tumors or scar tissue. Although their etiology remains unknown, we hypothesize a derivation from dermal melanocytes, in keeping with the Hochsteigerung theory of nevogenesis. The purpose of this study is to draw attention to the existence of incidental cutaneous nevic aggregates, thereby alerting pathologists and dermatopathologists to their potential as a diagnostic pitfall, especially in the setting of concurrent primary cutaneous malignant melanoma or melanoma in situ.

Laser capture microdissection: methods and applications.

Laser microdissection is a nonmolecular, minimally disruptive method to obtain cytologically and/or phenotypically defined cells or groups of cells from heterogeneous tissues. It is a versatile technology and allows the preparation of homogenous isolates of specific subpopulations of cells from which RNA/DNA or protein can be extracted for RT-polymerase chain reaction (PCR), quantitative PCR, Western blot analyses, and mass spectrophotometry.