Quantitative Analysis of Invasive Front in Tongue Cancer Using Ultrasonography

Purpose Ultrasonography is a useful diagnostic modality for the head and neck region. The mode of invasion is one of the predictive factors for the cervical lymph node metastasis. The purpose of this study is to evaluate the correlation between quantified invasive fronts from ultrasonographic images and the pathological malignancy grading of tongue squamous cell carcinoma. Materials and Methods Forty-eight previously untreated T1-2N0 tongue squamous cell carcinoma patients were enrolled. The ultrasonographic images of intraoral lesions and the excised lesions were collected. The invasive front on the ultrasonographic image was analyzed by a multipurpose software package. The length of the invasive front and the line of smoothed invasive front were measured and the invasive front ratio was calculated. The hematoxylin and eosin stained sections were assessed according to modified Jakobsson's malignancy grading as low and high malignancy grade groups. The correlation between invasive front ratio and the histological malignancy grade groups was evaluated. Results The mean invasive front ratio for the excised lesions was 1.145 in low malignancy grade group and 1.248 in high malignancy grade group. These values as determined for the intraoral lesions were 1.074 in the low malignancy grade group and 1.174 in high malignancy grade group. Significant statistical differences were observed between the 2 groups by Mann-Whitney's U test in both images. Conclusions Invasive front ratio is related to the histological malignancy grade group. It can be considered to be a valuable diagnostic method which can predict neck node metastasis, and help surgeons to choose adequate neck treatment.