Carcinoma in situ of the larynx. Results with different methods of treatment

A series of 81 cases of severe dysplasia or carcinoma in situ of the larynx was retrospectively analysed to evaluate the results of radiation therapy and repetitive stripping/biopsies. An average of almost five years elapsed between the diagnosis of severe dysplasia/carcinoma in situ and carcinoma. Of patients primarily treated with irradiation 19% developed invasive carcinoma compared to 15% in the group primarily treated with repetitive stripping/biopsies, and radiation therapy for failures. The mean age at diagnosis for patients in whom the epithelium normalized was 66.1 years, compared to 59.3 years for those in whom the process progressed to carcinoma (p less than 0.05). It thus appears that carcinoma in situ may comprise at least two different lesions with different biological behaviour.