Table 5.
Description of trichoscopic findings in erythrodermic cutaneous T-cell lymphoma (CTCL) with histopathological correlation.
| Trichoscopic features | Description | Possible histopathological correlation |
|---|---|---|
| Pili torti | Twisted dystrophic hair shafts | Folliculotropic inflammation without or with mucinous degeneration of the hair follicle induces pressure in the epithelium affecting hair shaft formation |
| Broken hairs | Short hairs with irregular distal ends; in CTCL they are the result of the breakage of pili torti | Folliculotropic inflammation without or with mucinous degeneration of the hair follicle induces pressure in the epithelium and influences hair shaft strength |
| Black dots | Residues of pigmented hairs broken or destroyed at scalp level; in CTCL they are the result of the breakage of pili torti | Folliculotropic inflammation without or with mucinous degeneration of the hair follicle induce pressure in the epithelium and influences hair shaft strength |
| Numerous yellow dots | Empty follicular openings filled with sebum and keratin | Indication of non-cicatricial alopecia caused by folliculotropic inflammation suppresing hair epithelium proper function |
| 8-shaped hairs | Long, pigmented, very thin hairs which are repeatedly rolled in two opposite directions forming structure resembling number 8 | Folliculotropic inflammation without or with mucinous degeneration of the hair follicle induces pressure in the epithelium and results in hair thinning |
| Visible anagen bulbs | Rectangular and dark pigmented hair bulbs, which are seen on scalp surface | Can be the result of elevation of the root of the anagen bulb induced by expanding upwards folliculotropic infiltration |
| Big, reddish areas | Red, patchy background color sized of a few follicular units | Intra- and perifollicular inflammatory infiltrate from the bulb to the infundibulum |
| Patchy hyperpigmentation of the background | Brownish patchy background color sized of a few follicular units | Lichenoid infiltrate of the epidermis or upper part of hair epithelia with keratinocytes damage and pigment release |
| Thick white bands localized interfollicularly | Whitish background color seen as thick bands between follicular units | They correspond probably to the pushed aside and upwards collagen fibers by surrounding inflammatory infiltrate, mucin deposits and hair epithelium degeneration |
| Perifollicular arrangement of glomerular or linear vessels | Glomerular or linear vessels localized around follicular units | Heavy perifollicular lymphocytic infiltrate pushes up and flatten superficial vascular plexus to form glomerular and linear perifollicular arrangement |
| Follicular spicules-like scales | Triangular in shape keratotic structures emerging from follicular orifices | Perifollicular inflammation and lymphocyte epidermotropism affect keratinocyte maturation and desquamation leading to spicules formation |