|Description||This chapter describes the criteriaThis glossary term has not yet been described. of solar lentiginesThis glossary term has not yet been described..|
|Author(s)||Ralph P. Braun · Stephanie Nouveau|
|Owner||Ralph Braun → send e-mail|
|Status update||May 28, 2017|
|Status by||Ralph P. Braun|
Solar lentiginesThis glossary term has not yet been described. are sharply circumscribed, uniformly pigmented macules that are located predominantly on the sun-exposed areas of the skinThis glossary term has not yet been described., such as the dorsum of the hands, the shoulders, and the scalp. Lentigines are a result of hyperplasia of keratinocytes and melanocytes, with increased accumulation of melanin in the keratinocytes. They are induced by ultraviolet light exposure. Unlike freckles, solar lentigines persist indefinitely. Nearly 90% of Caucasians over the ageprocess of becoming older of 60 years have these lesions. Due to the increased prevalence of lentigines in the elderly, these lesions are sometimes referred to as “lentigo senilis”. However, younger individuals who tend to burn after ultraviolet exposure can also develop lentigines after acute or prolonged ultraviolet light exposure. Clinically, solar lentigines may be oval, round, or irregular in shape and can vary from a few millimeters to a few centimeters in diameter. Most lesions have a uniform light brown 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.; however, there are instances when they vary from dark brown to black. One variant of solar lentigoThis glossary term has not yet been described., “ink-spot” lentigo, has a jet-black color. Actinic purpura or other signs of solar damage can frequently be found in the skin surrounding solar lentigines. Solar lentigines are benignThis glossary term has not yet been described. lesions that can evolve to a pigmented seborrheic keratosisThis glossary term has not yet been described.. Histologically, it is characterized by club-shaped rete ridges with small nub-like extensions. In addition, there is an increased number of melanocytes and increased pigmentation in the basal keratinocytes. Although most solar lentigines are easily recognized on clinical examination, some lesions pose diagnostic challenges because their clinical appearance resembles that of melanomaThis glossary term has not yet been described.. DermoscopyDermoscopy is a non invasive diagnostic method. can be helpful in correctly differentiating a solar lentigo from melanoma. The key dermoscopic features of solar lentigines are as follows:
The presence of a sharply demarcated and irregularly curved border is characteristic of solar lentigines. Often, portions of the border are scalloped, giving a motheaten appearance
Homogenous light brown pigmentation
Many lesions have no structures or networks, only containing light brown and structureless areas; the term “jelly sign” had been proposed to describe the pigment quality of these lesions. The pigment appears as if jelly had been smeared on the skin surface.
Pigment networkGrid-like pattern consisting of interconnecting pigmented lines surrounding hypopigmented holes.
There may be an area of faint, reticulation. This correlates with the presence of melanocytes and melanin-filled keratinocytes in the rete ridges.
They are areas consisting of fi ne parallel running lines of light brown to dark brown colors. They resemble the dermatoglyphics of a human fingerprint.
Lentigines located on the scalp and faceThis glossary term has not yet been described. share features of pigmented melanocyticThis glossary term has not yet been described. lesions in this special location revealing a pseudonetworkA structureless pigment area interrupted by non-pigmented adnexal openings pattern. This is created when a diffusely pigmented area is interrupted by nonpigmented adnexal openings
In a solar lentigo the pigment around hair follicles is distributed in a symmetric fashion creating small brown circles. The pigment is usually light brown in color and similar to the color of the rest of the lesion. While the pigment is usually distributed symmetrically around the follicle, some follicles may appear asymmetrically pigmentedThis glossary term has not yet been described.. These asymmetrically pigmented follicles appear as brown crescent shaped structures. However, these asymmetric follicles will also have a brown color like the rest of the lesion. If the color of the pigment around the follicle, whether symmetric or asymmetric, is of a grayish hue or differs from the rest of the lesion then melanoma needs to enter the differential diagnosisThis glossary term has not yet been described.. Ink-spot lentigines have their own distinct dermoscopic pattern.These lesions have a very prominent blackpigmented network, which has an almost three-dimensional quality under dermoscopyDermoscopy is a non invasive diagnostic method.. The network lines can be either thin or thick in width, and the network ends abruptly at the edge of the lesion