Association of gene mutations with clinicopathologic features in patients with external auditory canal squamous cell carcinoma

• Published in: International journal of clinical oncology Vol. 27; no. 9; pp. 1394 - 1403
• Main Authors: Morita, Shinya, Kano, Satoshi, Hatanaka, Kanako C., Hatanaka, Yutaka, Suzuki, Takayoshi, Fukuda, Atsushi, Hoshino, Kimiko, Fujiwara, Keishi, Nakamaru, Yuji, Homma, Akihiro
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01-09-2022; Springer Nature B.V
• Subjects: Cancer Research; Ear canal; Medicine; Medicine & Public Health; Mutation; Next-generation sequencing; Oncology; Original Article; p53 Protein; Phenotypes; Squamous cell carcinoma; Surgical Oncology; Tumorigenesis; External auditory canal cancer; Squamous cell carcinoma; Next-generation sequencing; Clinicopathologic features; Gene mutations
• ISSN: 1341-9625; 1437-7772
• DOI: 10.1007/s10147-022-02191-z

Background
External auditory canal squamous cell carcinoma (EACSCC) is a rare form of malignant tumor. Due to the extremely limited understanding of the genomic landscape in EACSCC, the association between gene mutations and clinicopathologic features remains unclear. This study aimed to explore somatic gene mutations associated with the clinicopathological features in patients with EACSCC, and to identify the candidate gene mutations for predicting survival outcome in EACSCC.
Methods
Twenty-two tissue samples obtained from patients with EACSCC were analyzed for genetic mutations based on targeted next-generation sequencing and genetic expression based on IHC staining to investigate the driver of tumorigenesis and/or the candidates of genes for predicting clinical outcome in EACSCC.
Results
Gene alterations were most frequently observed in
TP53
(59.1%), followed by
CREBBP
(9.1%).
TP53
mutations showed significant correlation with T classification (
P
 = 0.027) and p53 expression phenotype (
P
 < 0.001). The 5-year overall survival (OS) rates for EACSCC patients with
TP53
mutations and wild-type
TP53
were 45.0% and 75.0%, respectively. Multivariable analysis using the Cox proportional hazards model demonstrated that
TP53
mutations were independent predictors of OS rates for EACSCC patients (
P
 = 0.007).
Conclusion
This study has suggested that
TP53
mutations have potential for use as a biomarker for identifying individuals at high risk of developing tumors and for predicting survival outcome in EACSCC. IHC staining for p53 might play a useful role as screening tool for detecting
TP53
mutations in patients with EACSCC.