Accuracy of Biopsy in Subtyping Periocular Basal Cell Carcinoma

Abstract

Purpose: To determine the accuracy of initial biopsy in the diagnosis of basal cell carcinoma (BCC) histologic subtype.

Methods: Retrospective histopathologic review of patients with a diagnosis of primary periocular BCC from 2006 to 2013 inclusive.

Results: A total of 174 primary BCCs were identified. BCCs were classified as nodular, superficial, or aggressive (including mixed cases with an aggressive component). Punch biopsies were used in 41% of cases, while the remaining patients underwent shave or incision biopsies. The final histologic subtypes at excision were nodular (59%), superficial (7%), nodular and superficial (7%), and aggressive (51%). The overall concordance between the BCC subtype identified in the biopsy specimen and the subsequent excision specimen was 54%. In total, there were 51 cases (29%) of BCC, which included aggressive subtypes, of which 52% of initial biopsies failed to detect an aggressive component. There were 45 cases (26%) of mixed BCC, and an aggressive histologic subtype was present in 73% of these cases.

Conclusions: The accuracy of initial biopsy for BCC histologic subtype at excision is highest for nodular BCC. For aggressive BCC, biopsy was able to detect the aggressive component in only 48% of cases. This may have implications for choice of treatment modality.