[Correlation between high-risk TP53 mutation and extracapsular spread in oral squamous cell carcinoma]

To investigate the correlation between high-risk tumor protein p53 (TP53) mutation and extracapsular spread(ECS) in oral squamous cell carcinoma (OSCC).

The data of 88 OSCC patients admitted to Gansu Provincial People's Hospital from January 2013 to January 2016 were retrospectively analyzed. The patients were divided into non-lymph node metastasis group (A1), lymph node metastasis without ECS group (A2), lymph node metastasis with ECS group(A3) according to the presence or absence of lymph node metastasis. The deletion of exon 5-8 of TP53 gene in primary and metastatic lesions was detected. The correlation of ECS with disease-free survival(DFS), overall survival(OS) rate and TP53 mutation were determined, and single factor analysis of ECS was performed. The data were analyzed by SPSS 20.0 software package.

TP53 (5) homozygote deletion was found in all three groups. TP53 (6) homozygous deletion was found in group A3 (10/30). No homozygous deletion of TP53(7) was found in three groups.Homozygous deletion of TP53 (8) was found in group A2(7/42), group A3(10/30) and group A3(10/60).The 1-year and 3-year DFS rates were 75.00% and 70.83% in group A1, 70.59% and 58.82% in group A2, 46.67% and 40.00% in group A3, with significant difference(P<0.05). The 1-year and 3-year OS rates were 83.33% and 75.00% in group A1, 73.53% and 50.00% in group A2, 46.67% and 40.00% in group A3 , with significant difference(P<0.05). In group A3, there were 4 cases (13.33%) of low-risk TP53 mutation (LR), 12 cases (40.00%) of high-risk TP53 mutation (HR), 4 cases(13.33%) of wild-type TP53 mutation (Wt), and 10 cases(33.33%) of other mutations. HR mutation and other mutations occurred more frequently than other types(P<0.05). Smoking, primary lesion size, wild type/low risk and high risk/others were correlated with ECS(P<0.05).

ECS is an important marker of DFS and OS in OSCC patients, and high-risk mutations were common in ECS, indicating a certain correlation between high-risk mutations of TP53 and ECS in OSCC.