Reliability of biopsy margin status for basal cell carcinoma: a retrospective study

The reporting of biopsy margin status for basal cell carcinoma (BCC) varies among dermatopathologists. For biopsy specimens with seemingly negative margins, the question arises if the tumor extends beyond the margin in unexamined sections. We sought to determine the reliability of negative margin status for BCC and identify if any factors were predictive of positive true margins. We examined BCC biopsy specimens initially determined to have negative margins after routine sectioning and re-evaluated the margin status after complete tissue block sectioning of the initial biopsy specimen was performed. Our findings remind clinicians of the limitations of margin assessment and provide impetus for dermatopathologists to consider modifying how margin status is reported.