Prognostic factors in squamous cell carcinoma of the lower lip - an immunohistochemical study

Squamous cell carcinoma (SCC) of the lip represents 15-30% of SCC of cephalic extremity, located on the lower lip in about 90% of cases. The present paper aimed to define the profile of SCC of the lip with major risk factors. The study included 20 selected cases diagnosed with lower lip SCC, using a panel of antibodies which addressed cell proliferation (Ki67), perturbation of the cell cycle (p53), angiogenesis (VEGF - vascular endothelial growth factor), factors related to tumor cell interaction with the extracellular matrix (CD44). Ki67 immunoexpression was identified in all the cases. Poorly differentiated (PD) SCC presented a mean value of Ki67 positivity index (PI) significantly higher compared to well-differentiated (WD) and moderately differentiated (MD) SCC. We found significantly higher mean values of Ki67 PI in pT3 lesion, compared with pT2 and pT lesions, and with no statistically significant differences in lip SCC with associated lymph node metastasis (pN1), compared to those with no lymph node metastasis (pN0). PD SCC presented a higher mean value of p53 PI compared to WD and MD SCC, but without significant differences. Analysis indicated significantly higher values in pT3 lesions and in pT2 and pT1 and in pN1 SCC. In WD SCC, CD44 immunoexpression had a higher intensity. For PD and MD SCC the immunolabelings presented low÷moderate heterogeneous intensity. WD lip SCC presented a statistically significant higher mean value for CD44 PI compared to MD and PD SCC, and not statistically significant higher in pT1, pT2 then in pT3 and in pN0 cases then in pN1. WD lip SCC presented statistically significant higher mean value of VEGF PI related to those with MD and PD SCC. VEGF PI values were higher in pT1, pT2 then in pT3 and in the pN0 SCC, but without statistically significant differences. We found a positive linear correlation for Ki67÷p53, although statistically not significant and for CD44÷VEGF statistically significant (p=0.001). Also, the analysis identified negative a linear statistically significant correlation for Ki67÷CD44 and for Ki67÷VEGF statistically significant as well (p=0.001). Immunohistochemical investigations in lip SCC, regarding the expression of p53, Ki67, CD44 and VEGF, revealed results that suggest their ability to assess the prognosis and progression of tumor evolution.