Melanoma amelanotic C43.L

The average age of patients is over 50 years (Gong HZ et al. 2019).

Little characteristic clinical picture. Mostly clinically asymptomatic, little noticed, red, reddish-brown or skin-coloured, 0.2-1.0 -2.0 cm plaque/nodules with smooth, eroded or ulcerated, also crusty surface. The discoloration of an originally dark coloured malignant melanoma can apply to all tumour types. In this respect the clinical variability is very large. This also applies to its almost ubiquitous localisation.

The so-called ABCD rule is only partially applicable:

• A = Asymmetry (unequal halves on both sides of an imaginary centre line) - applies
• B = Border irregularity - applies
• C = Colour variation, especially the occurrence of brown and black tones(most important criterion - not applicable)
• D = Diameter (diameter): more than 5 mm or size growth (applicable)

Incident light microscopy: reddish or skin-coloured nodules, possibly remains of the pigment network.

High-resolution sonography (see sonography, 20 MHz sonography): see malignant melanoma.

Melanin detection is often only possible with special stains (silvering).

Tumor cells stain predominantly with HMB 45- and S100.

Less favorable than pigmented melanomas, as amelanotic malignant melanomas become clinically symptomatic late or are even discovered incidentally (Gong HZ et al. 2019).

1. Adler MJ, White CR (1997) Amelanotic malignant melanoma. Semin Cutan Med Surg 16: 122-130
2. Gong HZ et al.(2019) Amelanotic melanoma. Melanoma Res 29:221-230.
3. Peterson J, Rowley M (2007) Rhinophymatous amelanotic melanoma. Cutis 79: 383-386
4. Yesil S et al (2007) Amelanotic melanoma misdiagnosed as a diabetic foot ulcer. J Diabetes Complications 21: 335-337