For all hematogenously spread metastatic tumors,
the most common site of involvement within the temporal
bone is the petrous apex followed by the tegmen
(middle cranial fossa dural plate), mastoid bone, and
internal auditory canal.
Temporal bone metastases from noncontiguous,
distant primary lesions are thought to occur via the
1. Hematogenous spread of carcinoma with seeding of
the marrow spaces of the petrous bone.
2. Cerebrospinal fluid dissemination through the subarachnoid
space and into the IAC resulting in temporal