METHODS: Four cases of SCC initially occurring on the tongue dorsum were evaluated for clinical and histological findings and immunohistochemical expression of p53 and p16. Gene mutations were analyzed using next-generation sequencing with a custom panel of driver genes.
RESULTS: We retrospectively investigated 557 cases of tongue SCC, and only four cases of SCC initially occurred on the tongue dorsum. The four patients (cases 1-4) were one woman and three men with a mean age of 53.75 years (range: 15-74 years). Histological analysis revealed well-differentiated SCC. Through molecular analysis, we identified pathogenic somatic mutations, namely, TP53 p.C176F (c.527G > T) in case 3 and TP53 p.R282W (c.844 C > T) in case 4. No pathogenic variants were identified in the PI3K/AKT or RAS/RAF pathways. The p53 immunohistochemical examination revealed a wild-type expression pattern in cases 1-3 and strong expression in case 4. The results of p16 immunostaining were negative in all cases.
CONCLUSIONS: We described four previously unreported genetic characteristics of dorsal tongue SCC. Somatic TP53 mutations may contribute to the development of a subset of dorsal tongue SCC; however, more cases with genetic analysis need to be accumulated.
方法:对4例最初发生在舌背端的SCC进行临床和组织学观察以及p53和p16的免疫组织化学表达。使用下一代测序与一组定制的驱动基因分析基因突变。
结果:我们回顾性调查了557例舌鳞状细胞癌,只有4例SCC最初发生在舌背。四名患者(病例1-4)为一名女性和三名男性,平均年龄为53.75岁(范围:15-74岁)。组织学分析显示分化良好的SCC。通过分子分析,我们确定了致病性体细胞突变,即,在案例3中TP53p.C176F(c.527G>T)和在案例4中TP53p.R282W(c.844C>T)。在PI3K/AKT或RAS/RAF途径中未鉴定出致病变体。p53免疫组织化学检查显示在病例1-3中为野生型表达模式,在病例4中为强表达。所有病例的p16免疫染色结果均为阴性。
结论:我们描述了舌背SCC的四个以前未报道的遗传特征。体细胞TP53突变可能有助于背舌SCC子集的发展;然而,需要积累更多的遗传分析病例。