ABSTRACT
References 553
The estimated incidence of temporal bone (TB) malignancy by the National Cancer
Institute is 0.8-6 cases per million population per year (1,2). Squamous cell carcinoma
(SCCA) represents the majority of these cases (3-6). SCCA, a rare neoplasm with an
overall aggressive nature and poor prognosis, is estimated to comprise 90% of all primary
malignant tumors originating in the TB (7-9). Kuhel et al. (10) described the sites of
origin for TB SCCA: auricle (60-70%), the external auditory canal (EAC) (20-30%),
and the middle ear (10%). There is a report of isolated SCCA in situ of the tympanic
membrane (11). The advanced nature of lesions frequently makes it harder to assess the
site of origin. Most reports found a peak age incidence of SCCA of the EAC to occur in
the mid-50s (5,10,12). However, the population developing middle ear malignancy
appears to be 10 years younger (13). From conflicting data of multiple studies on the sex distribution of SCCA of TB, it appears that the distribution is equal between men
and women (3,5,14-17).
