The effect of 595 nm pulsed dye laser on superficial and nodular basal cell carcinomas

Basal cell carcinomas (BCCs) have supporting vasculature that could serve as a target for 595 nm pulsed dye laser (PDL). The objective of this study was to determine the effect of repeated PDL treatments on BCCs of superficial and nodular subtypes and of varying diameters.

Twenty biopsy-proven BCCs received four 595 nm PDL treatments at 2-week intervals. The tumor and 4 mm of peripheral skin were treated using a set of previously optimized laser parameters: one pass, 15 J/cm2 energy, 3 ms pulse length, no cooling, and 7 mm spot size with 10% overlap. The treated area was excised and evaluated histologically for residual tumor. Histologic response rates of the PDL treated BCCs were compared with that of non-PDL treated, matched control tumors.

Nearly all BCCs <1.5 cm in diameter (n = 12) showed complete response to four PDL treatments (91.7%; n = 11/12) versus 16.7% of controls (n = 2/12, P-value = 0.0003). BCCs > or =1.5 cm in diameter (n = 8) showed a complete response rate of 25% (n = 2/8) versus 0% of controls (n = 0/8, P-value = 0.2). Mean clinical tumor diameter of the complete responders was 1.1 cm (n = 13) versus 2.2 cm (n = 7) for incomplete responders (P-value = 0.005). Tumor histologic types among the complete responders included superficial, nodular, micronodular, and keratinizing. Incompletely responding BCCs showed a significant reduction in tumor burden after PDL treatment, with residual histologic tumor burden ranging from <1% to 29% of the original clinical tumor diameter, compared to 13-68% residual tumor burden for the corresponding controls (P-value = 0.05).

PDL is an effective means of reducing tumor burden in patients with large BCCs and may be an alternative therapy in BCCs <1.5 cm in diameter.