A tiny invasive melanoma: a case report with dermatoscopy and dermatopathology

Abstract

We present a case of an early invasive melanoma (Breslow thickness 0.25 mm), 1.6 mm in diameter on the arm of a 38-year-old woman. She was under surveillance due to having multiple (>100) nevi, and the melanoma was assessed as a new lesion by the examining doctor. Clinically the lesion was hyper-pigmented compared with surrounding nevi and dermatoscopically it had a clue of pseudopods/lines radial, but they were arranged in an arguably symmetrical circumferential pattern around a structureless blue-gray center. Generally melanomas are expected to be dermatoscopically asymmetrical, but we believe that this case illustrates the fact that small melanomas may be recognized by clues such as pseudopods/lines radial and dermatoscopic gray even when they have not yet developed unequivocal asymmetry.

Dermatoscopy of a melanoma less than one millimeter in diameter

“…Previously dermatoscopic features of four minute melanomas with a diameter of 1.5–2 mm were reported . One of these minute melanomas was invasive . The present case, with a maximum diameter of 0.9 mm, is the smallest melanoma that has ever been reported, and it presented as a changing lesion on an adult with dermatoscopic subtle gray color, these features being sufficient according to the Chaos and Clues algorithm to warrant excisional biopsy.…”

“…Previously dermatoscopic features of four minute melanomas with a diameter of 1.5–2 mm were reported . One of these minute melanomas was invasive .…”

When algorithms falter: a case report of a very small melanoma excised due to the dermatoscopic “ugly duckling” sign

“…It has previously been reported that small melanomas may not be asymmetrical [1,2]. It has also been reported that hyperpigmentation was the defining feature in all of 13 small melanomas (<4 mm diameter) in one series of 95 melanomas [12], but Pellizzari et al pointed out that this may in fact be due to selection bias, with darker lesions being discovered, while paler, hypomelanotic lesions may not be suspected at the stage where they are very small [2]. …”

“…Another recent case report by Pellizzari et al suggests that in very small lesions chaos (asymmetry of structure or color) may not be unequivocally present [2]. This particular melanoma had the diagnostic clue of lines radial, but as with the smallest published invasive melanoma [2], the radial lines were distributed circumferentially and any asymmetry was equivocal.…”

Experience in the diagnosis of skin melanoma smaller than 6 mm in diameter

“…По результатам гистологического исследования, все опухоли были представлены поверхностно-распространяющейся формой меланомы, а шесть образований были in situ [7]. В зарубежной литературе [8][9][10] встречаются описания единичных случаев меланомы кожи диаметром не более 2 мм.…”