Evaluating lingual carcinoma for surgical management: what does volumetric measurement with MRI offer?

MRI plays a crucial but under utilized role in the surgical management of lingual squamous cell carcinoma (SCC). Measurement of three-dimensional tumour volume (TV) has the potential to guide management of clinically negative cervical lymph nodes and address deficiencies in current TNM staging criteria. This work studied the value of MRI-measured TV as a predictor of 2 year disease-related survival (DRS) and disease-free survival (DFS), as well as occult cervical lymph node metastasis (OM) in lingual cancer. TV was determined by manually segmenting the tumour contour in each image slice and using the resulting pixel value to calculate the three-dimensional extent of disease. TV was also compared with the more established measure of tumour thickness (TT). Significant differences in DRS (chi(2)(1) = 7.7, Hazard ratio (HR) = 7.3, p = 0.005) and DFS (chi(2)(1) = 5.6, HR = 4.3, p = 0.02) at two years were found using a cut-off of 8 cm(3). Similarly, a significant relationship between TV and occult cervical lymph node metastasis was discovered using a 3 cm(3) cut-off (OR = 6.7, p = 0.02, Fisher's Exact Test).