The clinical target volume delineation based on the correlation analysis of neck node levels in oral cavity squamous cell carcinoma (OCSCC)

The delineation of clinical target volume (CTV) base on the correlation analysis between neck node levels of OCSCC has not been reported in detail. This study analyzes the correlations between the neck node levels in 208 cases of OCSCC, and aims to provide preliminary reference for the CTV delineation in OCSCC patients.

The records of 208 OCSCC patients were retrospectively analyzed. The neck node levels were evaluated according to the 2013 updated guidelines. The Chi-square test and logistic regression model were used to analyze the correlation of each level.

The most common involved level in OCSCC is Ib (45.7%) and IIa (40.4%). Correlation analysis of OCSCC showed that nodal spread in level Ia is related to levels Ib and VIa. Level Ib is related to levels Ia, IIa, IX. Level IIa is related to levels Ib, IIb, III. Level IIb is related to levels IIa, III, Va. Level III is related to levels IIa, IIb, Va. Level Va is related to levels IIb and III. Level VIa is related to level Ia and T stage. Level IX is only related to level Ib. T stage is only related to level VIa. All the above P values are < 0.05.

The related levels can be considered as high-risk region (HRR) and the unrelated levels as low-risk region (LRR) in the radiotherapy of OCSCC patients. This study can make the CTV delineation more individualized and accurate.