Treatment of Pigmented Basal Cell Carcinoma with 3 mm Surgical Margin in Asians.

Background. In Asians, most basal cell carcinomas (BCCs) are pigmented with clear borders. The consensus of 4 mm surgical margin for BCC largely depends on studies in nonpigmented BCCs in Caucasians. However, little is known about recurrences of pigmented BCCs with a narrower surgical margin. We aimed to investigate 5-year recurrence of BCCs, either pigmented or nonpigmented, in Taiwanese with 3 mm surgical margin. Materials and Methods. 143 patients with BCC (M/F = 66/77, average 64 years) were confirmed pathologically from 2002 to 2013. Based on the pathological margin (>1 mm, ≤1 mm, and involved), patients were categorized into the complete excision group (n = 77), histology with close proximity group (n = 43), and unclear surgical margin group (n = 23). Results. Among 143 cases, 105 were pigmented. With standard 3 mm excision, there were 7 recurrences, with 6 of them from nonpigmented BCC group. Logistic regression showed that pigmentation was associated with lower recurrence. Interestingly, 5-year recurrence of completely excised and histology with close proximity BCC (0/77 versus 1/43) was not different statistically. Conclusions. A 3 mm surgical margin is adequate for pigmented BCC. A "wait and see" approach rather than further wide excision is appropriate for BCC with <1 mm free margin.