Pediatric atypical spitzoid neoplasms: a review with emphasis on 'red' ('spitz') tumors and 'blue' ('blitz') tumors.

Background: The diagnosis of pediatric atypical Spitz nevus/tumors (pASNT) is an emerging challenge in clinical dermatology and dermatopathology.

Objective And Methods: We review the main clinicopathologic issues raised by pASNT and describe 2 examples of different clinicopathologic subsets of lesions.

Results: While Spitz/Reed nevi are commonly small- to medium-sized, tan to black plaques, pASNT are large and nodular, either 'red' (dotted and/or polymorphous vascular pattern on dermoscopy; spindle and/or epithelioid tumors on histopathology: Spitz tumors, sensu strictiori) or 'blue' (homogeneous blue color on dermoscopy; intimate admixture of epithelioid cells and heavily pigmented dendritic cells on histopathology: Blitz tumors or pigmented epithelioid melanocytomas).

Conclusions: Different clinicopathologic settings of pASNT probably exist. Dermoscopy can aid in their recognition and classification.