We analyzed retrospectively the case histories of 204 patients with squamous cell
hyperplasia of the larynx for the occurrence of multiple primary
tumors. All patients were grouped according to Kleinsasser's 1963 classification of laryngeal pathology. Patients with simple
hyperplasia (class I) had a low risk for developing a coincidental primary
tumor. The rist was 7% in patients with
hyperplasia with atypia (class II) and was 15% in patients with
carcinoma in situ (class III). This frequency is similar to that of our patients with glottic
cancer (13%). Although no coincidental
tumors were found in our female patients, the small number of females in our series made the differences in frequency between males and females not significant. This is still of interest to us because our previous study of patients with proven glottic
cancers also showed that no second
tumors occurred in our female patients. This difference was statistically significant. In our present study, all second
tumors occurred metachronously. Our findings indicate that all patients with class III
laryngeal disease (
carcinoma in situ) should undergo the same aggressive search for second primary
tumors, as do patients with invasive glottic
cancers. This means that panendoscopy or bronchoscopy should be done at the initial work-up and also at periodic intervals during the follow-up period. We have also found that patients lacking
immunoglobulin allotype Km(1) have to be followed aggressively, since these patients are at high risk of developing multiple
tumors. A possible exception can be made for female patients.