Carcinogenic effect of X-rays on the pharynx and larynx

In 19 patients receiving X-ray therapy carcinoma of the larynx or pharynx developed after years. Radiotherapy was applied in 2 cases for non-malignant diseases of the neck, in 1 case for infantile laryngeal papilloma, in 7 cases for precancerous laryngeal conditions in adults (6 papillomas, 1 leucoplakia), and in 9 cases of malignant laryngeal and pharyngeal neoplasms cured by this primary radiotherapy or combined treatment. In the latter group late secondary laryngeal or pharyngeal carcinoma developed 6-22 years after regression of the primary tumour (mean 15 years). This analysis is an attempt at demonstration in which cases the tumour was a consequence of past X-ray therapy, and in which the carcinogenic effect of X-rays on the pharynx and larynx was highly feasible. (author)