NODULAR ERYTHEMA-ELEVATUM-DIUTINUM MIMICKING CUTANEOUS NEOPLASMS

Aims: We describe the cutaneous pseudoneoplastic lesions in two patien ts with nodular erythema elevatum diutinum, a rare chronic disorder in which polymorph nuclear fragmentation (leukocytoclasis) is present wi thin dermal nodules showing spindle cells and fibrosis, In both cases diagnostic difficulty was encountered clinically and pathologically an d various benign and malignant neoplasms were considered in the differ ential diagnosis, Methods and results: Immunohistochemically the spind le cells were negative for CAM5.2, AE1/3, S100 protein and desmin (D33 ), They were positive for vimentin and focally positive for CD34 and a lpha-smooth muscle actin, Some of the spindle cells were positive for Mac 387 and KP1(CD68), By electron microscopy, the lesions were shown to consist of fibroblasts/myofibroblasts and fusiform macrophages. Con clusions: Increased awareness of the features described will help to a void misdiagnosis as a neoplastic process.