Histopathology of this pigmented lesion showed acanthotic epidermis with melanin pigmentation of basal keratinocytes and papillary dermal nodular accumulation of
melanophages and lymphocytes, which were consistent with tumoral melanosis.
Dermoscopy of the lesion typically shows gray-blue to bluish small dots over a bluish background, corresponding to melanin-laden
melanophages in deeper dermis (Tyndall effect), as is illustrated in the present case [12].
The vessels in the papillary dermis may be dilated and associated with inflammatory infiltrate.(1011) PBD shows the presence of increased melanin in basal layer and
melanophages in the dermis.
In LP-like GVHD, focal increases in the granular cell layer and vacuolar changes of basal layer often reveal in the epidermis, and
melanophages and a large number of lymphocytic infiltrate are common showing in the dermis.
Few inflammatory cells and
melanophages can be observed in the dermis [53, 58].
Histopathology shows increased melanin and a normal or slightly increased number of melanocytes in the basal layer of the epidermis and increased pigmentation within macrophages (
melanophages) in the papillary dermis [41].
Most cases of MS are benign though 10% of them are malignant with metastasis that is characterized by epithelioid cells with variably sized nuclei and marked accumulation of melanin in neoplastic cells and
melanophages [2, 5].
Horster et al., "Alterations in the epidermal-dermal melanin axis and factor XIIIa
melanophages in senile lentigo and ageing skin," British Journal of Dermatology, vol.
A biopsy may show signs of post-inflammatory infiltrate of the papillary dermis with dermal
melanophages. (4,5)
Rarely, small assemblies of dark pigmented cells (
melanophages) were found in the separating connective tissue septa.
Hyperkeratosis, acanthosis and
melanophages stained in brown-black colour are seen (crystal violetx400).
LP lesion may resolve with residual hyperpigmentation caused by a persistent increase in the number of
melanophages in the papillary dermis [96,100].
