Regression structures / Blue white structures
|Description||In this chapter we describe blue white structuresterm used for flat areas with white (scarlike) and blue color. This has to be distinguisehd from blue white veil. networkThis glossary term has not yet been described. and its histopathological correlation|
|Author(s)||Ralph P. Braun · Katrin Kerl|
|Responsible author||Ralph Braun → send e-mail|
|Status update||May 27, 2017|
|Status by||Ralph P. Braun|
- white scar-like depigmentationThis glossary term has not yet been described. (lighter than the surrounding skinThis glossary term has not yet been described.)
- “pepperingGray dots” (speckled multiple blue-gray granules)
On histopathologyThis glossary term has not yet been described. fully evolved regression shows fibrosis and melanosis (infiltrate of melanophages), and sparse lymphocytic infiltrates. The normal undulating DEJ pattern formed by rete ridgesEpidermal extensions that project into the underlying dermis and dermal papillae is attenuated to completely Flattened. Regression structures consisting of both scar like depigmentation and peppering (granularityThis glossary term has not yet been described.) should raise suspicion for melanomaThis glossary term has not yet been described.. Regression structures consisting of only peppering can be seen in melanoma, lichen planus like keratosisThis glossary term has not yet been described. and neviThis glossary term has not yet been described.. In lichen planus like keratosis the granularity tends to be coarse and diffusely distributed. In melanocyticThis glossary term has not yet been described. lesions the granularity tends to be finer and focally distributed.
dotsDots are small, round structures of less than 0.1 mm in diameter that have a red color when corresponding to blood vessels; however, when due to melanin, their color ranges from black, brown, to blue-gray depending on the depth and concentration of the melanin in the skin (Tyndall effect).. If a large area shows dense, confluent granularity, it is diffi cult to distinguish from blue-white veil, however, clinically, granularity often is seen in macular portions of the lesion, while blue-white veil in palpable areas. Histopathologically, granularity correlates with melanin in the superficialThis glossary term has not yet been described. dermis, either as fine melanin particles in melanophages or extracellular “dust-like” particles. When granularity is encountered in nevi it tends to encompass less than 10% of the lesion’s surface area. In contrast, in melanoma the granularity often encompasses more than 50% of the lesion’s surface area.
Blue-white veil is confluent blue pigmentation with an overlying white “ground-glass” haze. In melanoma, the bluewhite veil does not occupy the entire surface area of the lesion, but rather is present as a focal, ill-defined area. Histopathologically, this dermoscopic structure corresponds to an aggregation of heavily pigmented cells (melanocytes and/or melanophages) or melanin in the dermis (blue colorColor (American English) or colour (Commonwealth English) is the characteristic of human visual perception described through color categories, with names such as red, yellow, purple, or blue.) in combinationThis glossary term has not yet been described. with compact orthokeratosis . At times, it is difficultneeding much effort or skill to accomplish to distinguish between regression structuresThis glossary term has not yet been described. (namely melanosis) and blue-white veil by dermoscopyThe examination of [skin lesions] with a 'dermatoscope'. This traditionally consists of a magnifier (typically x10), a non-polarised light source, a transparent plate and a liquid medium between the instrument and the skin, and allows inspection of skin lesions unobstructed by skin surface reflections. Modern dermatoscopes dispense with the use of liquid medium and instead use polarised light to cancel out skin surface reflections. because both structuresThis glossary term has not yet been described. display blue-white color. However, examining the lesion without dermoscopy can helpRefers to giving assistance or support to others for mutual benefit differentiate between blue-white color due to regression versus due to deep melanocytes. In regression the surface contour will be flat (macular) and in blue-white veil the surface will be raised and palpable. In melanoma the blue-white veil is nonuniform in color and is present focally within the lesion. In contrast, the blue-white veil has a uniform steel-blue color in blue nevi and it occupies the entire surface area of the lesion.