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.

Prognostic Impact of Tumor Extension in Patients With Advanced Temporal Bone Squamous Cell Carcinoma

“…Dural involvement from preoperative imaging studies did not affect long-term tumor control and survival (25). Seligman et al (29) argued that dural invasion need not automatically be considered a surgical contraindication in all cases, noting that three of their four cases of TB-SCC survived for over 5 years following STBR. In our study, the invasion of the posterior cranial fossa dura significantly worsened the DSS rate (27.27%), and invasion of the middle cranial fossa dura showed a high HR (HR = 2.846).…”

“…Many authors continue to discuss the impact of dural invasion on prognosis ( 7 , 16 , 25 , 27 – 29 ). In 1994, Parasad et al reported that in cases where dural invasion was present, surgical resection did not improve overall survival after comparing 11 dural invasion cases with resection and nine dural invasion cases without resection.…”

“…Our study was conducted with the approval of the ethics review committee of both Kyushu University Hospital (permit no. [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] and Fukuoka University Hospital (permit no. 2017M091).…”

Genetic landscape of external auditory canal squamous cell carcinoma

“…Patient T989 had synchronously occurring bilateral EACSCC of both ears ( Figure 3A Although both primary tumors (T939L and T939R) had pathogenic somatic mutations in TP53, their genomic positions were different ( Figure 3C and Table S2). These results suggest that these tumors Fraction of Mutations (%) T 9 3 9 L T 9 3 9 R T 5 0 1 T 7 0 4 T 2 1 0 T 4 6 5 T 3 2 8 T 9 8 1 T 0 9 7 T 3 3 34,35 despite the functional contribution in the onset of EACSCC being unknown (Table S3).…”

“…External auditory canal squamous cell carcinoma (EACSCC) is a rare and aggressive malignant disease originating from squamous epithelial cells of the external auditory canal, which reportedly occurs in 1 to 6 cases out of 1 000 000 individuals per year, with poor overall survival. [1][2][3][4][5] Because of its rarity, an evidence-based treatment strategy for EACSCC has not yet been established; thus, it is clinically and biologically important to elucidate the molecular characteristics of EACSCC to discover novel therapeutic targets.…”