The following associations were found: positive association between MCT1 expression and older patients (p = 0.007, Table 4); CD147 positivity and bigger tumours and higher tumour penetration (p = 0.003, p = 0.034 Table 5); and GLUT1 with exophytic macroscopic appearance and low CEA levels (p = 0.023 and p = 0.050 respectively, Table 4), poorly differentiated tumours (p = 0.009, Table 5) and a trend to associate with the presence of lymph node metastasis (p = 0.058, Table 5). This evidence concerns the gene SLC2A1 and metastatic malignant neoplasm in the lymph nodes.