RESUMEN
BACKGROUND: Although the standard treatment of oral leukoplakia ranges from watchful waiting to complete resection, the value of these approaches is unknown. METHODS: We studied the relations among resection, ploidy status, and death from cancer in 103 patients with diploid dysplastic oral leukoplakia, 20 patients with tetraploid lesions, and 27 patients with aneuploid lesions. Data on cancer-specific mortality and treatment were obtained from the Cancer Registry of Norway, Statistics Norway, and chart reviews. RESULTS: Primary oral carcinoma developed in 47 of the 150 patients with leukoplakia (31 percent)--5 with diploid, 16 with tetraploid, and 26 with aneuploid leukoplakia--during a mean follow-up of 80 months (range, 4 to 237). The margin status of the initial leukoplakia resection had no relation to the development of oral cancer (P=0.95). Twenty-six of the 47 patients in whom cancer developed (4 with prior tetraploid and 22 with prior aneuploid lesions) had recurrences (55 percent); the recurrences were more frequently multiple and distant (within the oral cavity) among patients with aneuploid lesions than among those with tetraploid or diploid lesions. All 47 patients underwent a standard regimen of surgery and radiation, followed by chemotherapy in the 26 with recurrent cancer. Only patients with aneuploid leukoplakia died of oral cancer; the five-year rate of death from cancer was 72 percent. Aneuploidy-related first carcinomas were diagnosed at a more advanced stage than were carcinomas originating from diploid or tetraploid leukoplakia (P=0.03) and were more likely to be lethal regardless of the stage. CONCLUSIONS: Complete resection of aneuploid leukoplakia does not reduce the high risk of aggressive carcinoma and death from oral cancer.