There were cytologically atypical lymphoid cells that displayed epidermotropism
, Pautrier microabscesses, and a bandlike dermal distribution (A).
(single-cell exocytosis of lymphocytes into the epidermis) is present.
A diagnostic hallmark of MF is epidermotropism
, or presence of atypical lymphocytes in the epidermis.
A characteristic of lichen planus is epidermotropism
of the lymphocytic infiltration, and so keratinocytes are the target cells (3, 4, 5).
Finally, the lesion may also occasionally be due to epidermotropism
from a more distant rectal, urogenital, or adenocarcinoma arising from elsewhere .
Histopathologic finding of diffuse or nodular dermal and subcuticular infiltrate of plasma cells, displaying varying degrees of maturation and atypia but no epidermotropism
, are findings that are consistent with our patient.
The neoplastic cells also showed epidermotropism
. There were numerous mitoses and a variable chronic inflammatory infiltrate was admixed with the tumour cells (Figures 1 and 2).
The skin biopsy showed a predominance of folliculotropism (Figure 2c), compared to a less-remarkable epidermotropism
, with intraepidermal clusters of atypical lymphocytes larger than benign recruited dermal lymphocytes, as well as perinuclear vacuolization seen in the patch- and plaque-stage of MF (H&E stain, 2a, b.)
Skin biopsies of T-PLL cutaneous involvement classically show infiltrate of variable density of atypical lymphocytes in the superficial dermis, with a perivascular and periadnexal distribution with no epidermotropism
. (8) The atypical lymphoid cells are small to medium sized with markedly irregular nuclei and visible nucleolus.
One observes an interface infiltrate, and in the more advanced lesions, definite epidermotropism
. Pautrier's microabscesses are usually not found.
There was no evidence of epidermotropism
which ruled out the possibility of primary cutaneous lymphoma.
Histopathologically, BPDCN in the skin is characterized by a diffuse infiltrate of medium-sized blasts with high N:C ratio, scant cytoplasm, finely dispersed chromatin, and prominent nucleoli in the dermis underlying a Grenz zone without epidermotropism