Psoralen UVA therapy for linear and generalized morphea

Abstract

APL is characterized histologically by delicate, thin-walled, vascular spaces lined by endothelium in the papillary dermis. The vascular spaces form channels that run horizontally and have a dissection of appearance. There is no cellular atypia. In some cases the lesion extends to the mid and reticular dermis and even to the subcutis, and the vascular spaces in the deep tissue are smaller and have irregular appearance. 5 Immunohistochemical studies have given inconsistent results. Wilson Jones et al. 5 found that the lesional endothelial cells were UEA-1 positive and factor VIII-related antigen negative. Rosso, Gianelli, and Carnevali 9 found that factor VIII-related antigen was positive, whereas UEA1 was inconsistently reactive in the endothelial cells. Tadaki et al. 4 reported that in their case endothelial cells did not stain with either factor VIII-related antigen or UEA-1. Zhu et al. 6 found type IV collagen and desmin surrounding the vascular channels, suggesting that APL is a hamartoma that contains blood and lymphatic vessels as well as smooth muscle.