PIGMENTED BASAL-CELL CARCINOMA - INVESTIGATION OF 70 CASES

Background: Pigmented basal cell carcinoma (PBCC) is a clinical and-histologic variant of BCC. Objective: Our purpose was to identify the histologic subtypes of BCC that were most often associated with pigment and to determine whether this correlated with outcome after excision. Methods. A series of PBCC was identified and the histologic subtype noted. Margins of all excisions were examined for residual tumor. These results were then compared with a series of nonpigmented BCCs. Results: In a series of 1039 consecutive BCCs, 70 (6.7%) contained pigment. The histologic growth pattern most frequently associated with pigment was the nodular/micronodular pattern (12.4%) followed by the nodular (7.7%), superficial (7.2%), micronodular (4.0%), and the nodular/micronodular/infiltrative (3.4%) patterns. Margins were examined for evidence of residual tumor in the 40 cases that were excised. In only one case (2.5% was the margin positive for tumor. This was statistically significant (p < 0.05) compared with 388 excisions of nonpigmented BCCs with comparable growth patterns in which 69 (17.7%) showed positive margins. Conclusion: PBCC, as a clinical variant, is more frequently excised with adequate margins than are tumors of comparable histologic subtypes that do not contain pigment.