title: Proliferative nodules of undifferentiated spindle cells arising in a large congenital melanocytic naevus.
abstract: Proliferative nodules (PN) are benign lesions that arise in large congenital melanocytic naevi (LCMN). Clinically and histologically they can be difficult to differentiate from malignancies, which are also associated with LCMN. The PN in this case consisted of undifferentiated spindle cells and exhibited unusual histological features including negative stains for melanocytic markers (S100, HMB45 and MelA), negative stain for c-Kit, high mitotic index and unusual morphology of the lesional cells. As a result, a firm histological classification could not be made, which posed a challenge for the clinical management.
authors: Sydney Children's Hospital.
authors: Elizabeth M
authors: EM
authors: Christou
authors: Andrew Chih-Chieh
authors: AC
authors: Chen
authors: Ella
authors: E
authors: Sugo
authors: Draga
authors: D
authors: Barbaric
authors: Orli
authors: O
authors: Wargon
mesh_terms: D001415:Back; D002081:Buttocks; D002454:Cell Differentiation; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008940:Mitotic Index; D009363:Neoplasm Proteins / Q000032:analysis; D009378:Neoplasms, Multiple Primary / Q000737:chemistry / Q000151:congenital / Q000473:pathology*; D009508:Nevus, Pigmented / Q000737:chemistry / Q000151:congenital / Q000473:pathology*; D012878:Skin Neoplasms / Q000737:chemistry / Q000151:congenital / Q000473:pathology*; D013848:Thigh
chemical_list: D009363:Neoplasm Proteins
keywords: congenital melanocytic naevus; neurocutaneous melanocytosis; proliferative nodule; undifferentiated spindle cell