Effect Of Depth Of Invasion And Adjuvant Therapy Based On Depth Of Invasion On Prognosis Of Oral Squamous Cell Carcinoma

Objective: To understand the clinical significance of depth of invasion（DOI）in the eighth edition of TNM clinical staging system in improving the prognosis of patients with oral mucosal squamous cell carcinoma（OSCC）,to explore the predictive value of tumor depth of invasion on postoperative local recurrence and cervical lymph node metastasis of oral squamous cell carcinoma,and to analyze the impact of adjuvant therapy based on depth of invasion on the prognosis of patients.Methods: Collect and sort out the patients who received surgical treatment in the First Affiliated Hospital of University of science and technology of China（Anhui Provincial Hospital）due to primary oral mucosal squamous cell carcinoma from December 2008 to September 2016.The 7th and 8th TNM staging systems were used to classify all patients,understand the changes of staging and the differences in tumor recurrence,metastasis and survival rate between the two groups,evaluate the effect of DOI on postoperative local recurrence and cervical lymph node metastasis,and explore the effect of adjuvant therapy based on the depth of invasion.Results: According to the TNM staging standard of the eighth edition,the PT staging of patients has an obvious upward trend（P < 0.001）.In the p T1 sequence of the seventh edition,when DOI ≤ 5mm,the cervical lymph node metastasis rate and postoperative local recurrence rate of patients are 8.3% and 3.1% respectively.When5 mm < DOI ≤ 10 mm and DOI > 10 mm,the cervical lymph node metastasis rate is31.4% and 25.0% respectively（P = 0.029）.When 5mm < DOI ≤ 10 mm,the postoperative local recurrence rate of patients is 60.0% and DOI > 10 mm,The recurrence rate increased to 75.0%（P < 0.001）;Depth of invasion,as an important risk factor,resulted in poor overall survival（OS）and disease-related survival（DSS）in the seventh edition of early oral cancer sequence（p T1,P < 0.001）.Secondly,for patients with oral squamous cell carcinoma,the postoperative recurrence,recurrence time,cervical lymph node metastasis and pathological lymph node positive were closely related to the depth of invasion（P < 0.05）.For patients with oral squamous cell carcinoma grouped according to different depth of invasion,adjuvant treatment such as postoperative radiotherapy and chemotherapy has no significant effect on reducing postoperative local recurrence and cervical lymph node metastasis,improving or survival rate（P > 0.05）.Conclusion: The depth of tumor invasion has important predictive value for postoperative recurrence,cervical lymph node metastasis and survival rate.However,the depth of invasion can not be used as a separate index to guide whether adjuvant treatment such as radiotherapy and chemotherapy is needed after oral cancer surgery.