[The differential diagnosis of chronic tympanic effusion (author's transl)].

Three patients are reported in whom sound-conduction deafness was caused by malignant tumors in the tubal-tympanic area of the middle ear. In all patients, physical examination (inclusive of the ear and nasopharynx) had essentially been normal for a long time. In each patient, the tympanogram obtained indicated a tympanic effusion which, however, proved to be therapy-resistant. The first patient was found to have a malignant melanoma of the auditory tube while the second patient had an adenoid cystic carcinoma of the middle ear. The last patient had a primary carcinoma which at first showed only peritubal and submucosal growth.