Late occurring recurrence of oral cancer after combined treatment with bleomycin and radiotherapy.

Among 11 patients with oral cancer that disappeared after combined treatment with bleomycin and radiotherapy without surgery, one had an early recurrence and three had recurrences after 2 years or more. These late occurring recurrences were microcancers on mucous membranes that were thought to have been cured. Two of the three patients whose tumors recurred and another patient were found to have epithelial dysplasia at 1 year and 2 months, 4 years and 2 months, and 1 year and 3 months later, respectively. Among 59 patients who underwent surgery after the combined treatment, no viable cancer cells were found in the resected specimens of 20 patients, but moderate or severe epithelial dysplasia was noted in ten of the 20 patients. The present findings imply that patients in whom an apparent cure has been brought about by conservative treatment may harbor latent malignancy.