Dermal Clear Cell Mesenchymal Neoplasm
David S. Cassarino, MD, PhD
Key Facts
Terminology
Rare, dermal-based clear cell tumor of unknown derivation
Clinical Issues
Cutaneous nodule
Most cases have been reported on lower extremities
Uncertain, given rarity of this tumor, but appear to be benign or low-grade tumors
Microscopic Pathology
Clear cell proliferation
Cytologically, cells are usually bland-appearing, with vesicular nuclei and abundant clear cytoplasm
Top Differential Diagnoses
Clear cell sarcoma
Clear cell fibrous papule
Clear cell squamous cell carcinoma and trichilemmal carcinoma
 Low-power examination shows a dermal-based clear cell tumor with a thin Grenz zone  separating it from the overlying epidermis. (Courtesy A. Lazar, MD.) |
 Higher magnification shows the relatively bland cytologic features of the large clear cells with vesicular nuclei and abundant clear cytoplasm. (Courtesy A. Lazar, MD.) |
TERMINOLOGY
Abbreviations
Dermal clear cell mesenchymal neoplasm (DCCMN)
Definitions
Rare dermal-based clear cell tumor of unclear derivation
ETIOLOGY/PATHOGENESIS
Unknown
Very rare tumors of unknown etiology
CLINICAL ISSUES
Epidemiology
Age
Reported in adults over age 35
Site
Most cases have occurred on lower extremities
