Late recurrence or radiation induced cancer of the larynx.

Twenty five patients with squamous carcinoma of the glottis (T1a and T1b) had undergone successful irradiation. Many years later they developed a so-called late recurrence. The following evidence shows that these 'late recurrences' are radiation induced: the interval of 5-18 years (mean 9.9 years) between the first and the second cancer correlates with the interval seen usually in radiation induced malignancy, recurrences generally appear during the first 2 years after irradiation, all the second cancers were found in the previously irradiated area, in patients treated by surgery only, late recurrences are extremely rare, histological examination clearly shows that the second carcinoma originates from the squamous epithelium and not from dormant nests in the deeper layers of the vocal cord. These factors should be taken into consideration when deciding between surgical or radiation therapy in younger patients with high life expectation.