Results
Twenty patients (19 males and 1 female) with mean age of 60.95 ± 9.23 years diagnosed with LSCC were included in the study. 70% of the cases (14 patients) showed positive membranous expression of EGFR. Notably, 60% of the studied lymph nodes which were regarded as clinically and radiologically negative revealed to harbor occult metastasis, micro-metastasis or isolated tumor clusters (ITC) by showing malignant features and positive expression to EGFR immunohistochemical polyclonal antibody.
Notable association between T stage of the primary and the presence of occult metastasis as evidenced with immunohistochemical membranous expression of EGFR in neck lymph nodes of patients with N0 laryngeal squamous cell carcinoma (p=<0.001). Also, it was found that there is a correlation between the tumour grade and the immunohistochemical expression of EGFR in neck lymph nodes of patients with laryngeal squamous cell carcinoma (p=0.001) (table 1, figure 1).
In addition, it was found that there is a significant correlation between the neck nodal metastasis as detected by EGFR immunohistochemical staining and tumour cartilage invasion (p=0.05), lymphovascular invasion (p=0.028) & muscle invasion (p=0.05) detected by histopathological analysis of the total laryngectomy specimen (table 2, figure 1).
Our study showed a remarkable correlation between the laryngeal expression of EGFR and cervical lymph node metastasis as evidenced by EGFR immunohistochemical staining (p=0.001), as it was revealed that all the patients who had cervical node metastasis had positive EGFR expression in their primaries (table 3, figure 1).