Temporal bone carcinoma: Treatment patterns and survival

Abstract

Objectives/hypothesis: Carcinomas of the temporal bone are rare, and appropriate treatment, staging, and survival data are limited. This study evaluates clinical characteristics and survival rates for patients with temporal bone carcinoma treated with resection at a single tertiary-care institution, with a focus on the outcomes of patients with locally advanced disease including skull base and/or dural invasion.

Study design: Retrospective chart review.

Methods: Demographic, tumor-specific, and survival data were collected for patients with primary carcinomas of the external auditory canal with involvement of the temporal bone from 2003 to 2015. All patients were staged according to the modified Pittsburgh system. Kaplan-Meier and logistic regression analysis were used to calculate factor-specific survival outcomes.

Results: Sixty-seven patients met inclusion criteria; 85% were male. There were 43 squamous cell carcinomas (64%) and 24 basal cell carcinomas (BCCs) (36%). Tumor stage was 24 (36%) T2, 12 (18%) T3, and 31 (46%) T4 tumors; 53% had recurrent disease. Surgical management included 49 lateral temporal bone resections and 18 subtotal temporal bone resections. Kaplan-Meier analyses revealed more favorable 5-year survival rates associated with BCC histology (P = .01), lateral temporal bone resection compared to subtotal temporal bone resection (P < .01), lack of immunocompromise (P = .04), and absence of perineural/lymphovascular invasion (P = .01). Multivariate regression analysis did not yield statistically significant results.

Conclusions: Factors predictive of more favorable survival include lack of immunocompromise, BCC histology, absence of perineural/lymphovascular invasion, and disease extent amenable to lateral temporal bone resection. Dural invasion is not an absolute contraindication to surgery, with a subset of patients surviving >5 years.

Level of evidence: 3 Laryngoscope, 130:E11-E20, 2020.

Keywords: Temporal bone carcinoma; basal cell carcinoma; squamous cell carcinoma; temporal bone resection.

Figure 1.

Kaplan-Meier survival analyses of overall population. A. Overall survival of patients undergoing temporal bone resection according to T stage. Although T2 disease appears to have better survival outcomes than T3 and T4 disease, results did not reach statistical significance (p=0.16). B. Overall survival of patients undergoing temporal bone resection according to cancer histology. Patients with basal cell carcinoma (BCC) showed improved survival over patients with squamous cell carcinoma (SCC) (p=0.01). C. Overall survival of patients undergoing temporal bone resection according to type of temporal bone resection. Patients undergoing lateral temporal bone (LTBR) resection showed improved survival over patients undergoing subtotal temporal bone (STBR) resection (p<0.01). D. Overall survival of patients undergoing temporal bone resection according to presence of perineural/lymphovascular invasion. Patients without invasion showed improved survival over patients with invasion on final histopathology (p=0.01). E. Overall survival of patients undergoing temporal bone resection according to immune status. Patients who were immunocompetent showed improved survival over patients with immunocompromise (p=0.04).

Figure 2.

Kaplan-Meier survival analyses of subgroup of patients with squamous cell carcinoma (SCC) histology. A. Overall survival of patients with SCC undergoing temporal bone resection according to type of temporal bone resection. Patients undergoing lateral temporal bone (LTBR) resection showed improved survival over patients undergoing subtotal temporal bone (STBR) resection (p=0.03). B. Overall survival of patients with SCC undergoing temporal bone resection according to use of adjuvant radiation therapy. Patients undergoing adjuvant radiation showed improved survival over patients who did not have adjuvant radiation (p=0.02).