Introduction
SAENGEER,1 in 1900, related deafness to invasion of the acoustic nerve by neoplastic cells in the subarachnoid space secondary to carcinoma of the breast. The infiltration of the leptomeninges with carcinoma cells was called carcinomatous meningitis by Siefert2 in 1901. Since that time deafness in carcinomatous meningitis has been observed in many cases, but there have been relatively few histopathological studies of the inner ear in this disease. Knierim,3 in 1908, described the pathological findings in the temporal bone from a patient with a primary carcinoma of the stomach and rapidly progressive deafness. This was followed by reports of Schlitter,4 Wagener,5 and others,6-12 summaries of which are presented in Table 1.An additional form of inner ear and auditory nerve involvement with neoplastic cells results from the subarachnoid spread of cells from primary intracranial tumors. The mechanism of spread to the labyrinth in