Position paper on a simplified histopathological classification of basal cell carcinoma: results of the European Consensus Project.

Background: Histopathological classification of basal cell carcinoma (BCC) has important prognostic and therapeutic implications, but reproducibility of BCC subtyping among dermatopathologists is poor.

Objectives: To obtain a consensus paper on BCC classification and subtype definitions.

Methods: A panel of 12 recognized dermatopathologists (G12) from nine European countries used a modified Delphi method and evaluated 100 BCC cases uploaded to a website.