Copy number variation: A prognostic marker for young patients with squamous cell carcinoma of the oral tongue

• Published in: Journal of oral pathology & medicine Vol. 48; no. 1; pp. 24 - 30
• Main Authors: Gu, Xiaolian, Coates, Philip J., Boldrup, Linda, Wang, Lixiao, Krejci, Adam, Hupp, Ted, Fahraeus, Robin, Norberg‐Spaak, Lena, Sgaramella, Nicola, Wilms, Torben, Nylander, Karin
• Format: Journal Article
• Language: English
• Published: Denmark Wiley Subscription Services, Inc 01.01.2019; John Wiley and Sons Inc
• Subjects: Adult; age; Age Factors; Aged; Biomarkers, Tumor; Carcinoma, Squamous Cell - diagnosis; Carcinoma, Squamous Cell - genetics; Carcinoma, Squamous Cell - mortality; Copy number; copy number variation; Dentistry; DNA Copy Number Variations; Female; Genetic markers; Genomes; Geriatrics; Humans; Male; Medical prognosis; Middle Aged; Original; Patients; Prognosis; Ribonucleic acid; RNA; Squamous cell carcinoma; squamous cell carcinoma of the oral tongue; Survival Rate; Tongue; Tongue Neoplasms - diagnosis; Tongue Neoplasms - genetics; Tongue Neoplasms - mortality; Whole Exome Sequencing; Young Adult; squamous cell carcinoma of the oral tongue; copy number variation; prognosis; whole-exome sequencing; age
• ISSN: 0904-2512; 1600-0714; 1600-0714
• DOI: 10.1111/jop.12792

Background The incidence of squamous cell carcinoma of the oral tongue (SCCOT) is increasing in people under age 40. There is an urgent need to identify prognostic markers that help identify young SCCOT patients with poor prognosis in order to select these for individualized treatment. Materials and methods To identify genetic markers that can serve as prognostic markers for young SCCOT patients, we first investigated four young (≤40 years) and five elderly patients (≥50 years) using global RNA sequencing and whole‐exome sequencing. Next, we combined our data with data on SCCOT from the cancer genome atlas (TCGA), giving a total of 16 young and 104 elderly, to explore the correlations between genomic variations and clinical outcomes. Results In agreement with previous studies, we found that SCCOT from young and elderly patients was transcriptomically and also genomically similar with no significant differences regarding cancer driver genes, germline predisposition genes, or the burden of somatic single nucleotide variations (SNVs). However, a disparate copy number variation (CNV) was found in young patients with distinct clinical outcome. Combined with data from TCGA, we found that the overall survival was significantly better in young patients with low‐CNV (n = 5) compared to high‐CNV (n = 11) burden (P = 0.044). Conclusions Copy number variation burden is a useful single prognostic marker for SCCOT from young, but not elderly, patients. CNV burden thus holds promise to form an important contribution when selecting suitable treatment protocols for young patients with SCCOT.