Primary Advanced Squamous Cell Carcinoma of the Temporal Bone: A Single-Center Clinical Study

The extreme rarity of temporal bone squamous cell carcinoma (TB-SCC) has delayed the accumulation of high-quality clinical evidence. For the purposes of retrospective meta-analysis in the future, a large dataset with information from various institutions would be ideal. Our objective here was to retrospectively review cases of TB-SCC encountered at a single tertiary referral center and explore survival outcomes and prognostic factors.

Retrospective chart review.

The medical records of all TB-SCC cases were retrospectively reviewed. The resulting dataset contained 71 cases of primary cancer eligible for initial definitive (curative) treatment.

T4 status was associated with lower disease-specific 5-year survival than T1 to T3 staging (T1: 100%, T2: 92%, T3: 86%, T4: 51%). Survival was significantly higher in operable than in inoperable cases, even when restricted to advanced (T3/T4) cancers. The tumor extension to the middle ear cavity was observed in 13/17 of T3 cases, but it was not associated with poor survival. In addition, among operable cases, negative surgical margins were associated with significantly higher survival than positive margins.

Definitive treatments can offer disease-specific 5-year survival of over 85% in T1 to T3 cases of TB-SCC. The tumor extension to the middle ear cavity is not associated with poor survival. T4 status, inoperability, nodal invasion, and positive surgical margin are identified as a predictor of poor prognosis. Still, the matter of how to deal with unresectable tumors remains an outstanding issue in the treatment of TB-SCC.

4 Laryngoscope, 131:E583-E589, 2021.