The role of laser vascular targeting and retinoic acid in oral cancer inhibition.

Abstract

The study examines the role of the pulsed-dye laser at 585 nm, coupled with retinoic acid at therapeutic dose of 5.0 mg/kg body weight, in inhibiting chemically induced tumor growth in the hamster cheek pouch to determine whether pulsed-dye laser therapy can inhibit tumor growth and whether a combination of pulsed-dye laser and retinoic acid has a synergic effect on treatment efficacy. Randomized, prospective study of hamster model. Forty-eight male golden Syrian hamsters were painted with 0.5% solution of 9,10-dimethyl-1,2-benzanthracene in acetone for 6 weeks to induce dysplasia in both sides of the cheek pouches. The hamsters were then randomly divided into four groups of 12 hamsters each as follows: (1) control group, (2) pulsed-dye laser treatment only (8.0 J/cm(2) and two pulses), (3) retinoic acid treatment only (5.0 mg/kg/d by intraperitoneal injection), and (4) combined pulsed-dye laser and retinoic acid treatment. The treatment period was 40 days. Tumors were measured throughout the study. The results indicated that retinoic acid and pulsed-dye laser each significantly delay tumor growth and reduce tumor volume when used alone. Tumor volumes were statistically different among the treatment groups. There was also a statistical difference in tumor volume between the retinoic acid treatment group and the combined pulsed-dye laser and retinoic acid treatment group. The study demonstrated the greater advantage of combining pulsed-dye laser with retinoic acid over using either retinoic acid or pulsed-dye laser alone for delay of oral cancer progression. Clinical trials are warranted to establish efficacy in humans.