Sunday, August 29, 2010


View this YouTube video on LPLK. Click on the arrow and when it starts go to the bottom of the screen and change the 360 resolution to 1080 and then click on the box with the arrows pointing out to enlarge to full screen. These videos are recorded in high definition which makes for great viewing if you have a fast broadband connection. Press ESC on your keyboard to return to normal size.

The histology you see when you biopsy an LPLK depends on the stage at which you biopsy it. The acute stage with a red itchy plaque will show the features of acute Lichen planus with a band like lichenoid lymphocytic infiltrate, hypergranulosis, acanthosis and pink necrotic keratinocytes at the dermo epidermal junction. The late stage LPLK will show the results of all this basal layer damage with melanin in melanophages in the dermis, only minor lichenoid infiltrate and some fibrosis in the dermal papillae as a feature of scarring or complete regression. 
Intermediate lesions such as some illustrated above will show both acute lichenoid features in part of the lesion and the histology of the lesion undergoing regression elsewhere!

View the video of the histology of LPLK below.

Below is the edge of a LPLK Note the lichenoid infiltrate

Below is more acute histology with significant basal layer damage and necrotic keratinocytes

Below is a regressed solar keratosis Little infiltrate and melanin in melanophages in the papillary dermis