Neoneurogenesis in squamous cell carcinoma of tongue: a promoter to its progression and metastasis

Abstract Background : To explore whether neoneurogenesis is a predisposing factor to the development and metastasis of squamous cell carcinoma of tongue (TSCC) . Methods: Twenty patients diagnosed with TSCC were included. The objectives were divided into 4 groups according to WHO T-stage standard (five cases in each group) and 2 groups based on lymph node metastasis or not. Detection of neoneurogenesis in paraffin sections from primary tongue cancer tissues was stained by Neurofilament-Light chain antibody (NF-L) using immunohistochemistry method (IHC). The number of new growth nerve fiber bundles was calculated in each randomized view from 3 non-overlapping microscope fields of each tumor section under a light microscope at X 200. Differences in the density of nerve fiber bundles among the T-stage groups and lymph node metastasis groups were calculated using Chi-square test. An ɑ level of 0.05 was considered statistically significant. Results: The age of patients varied from 33 to 74 years with a mean age of 56.10±11.18 years. Males were affected predominantly with a ratio of 1.5:1 to females. IHC staining of NF-L was positive in all 20 paraffin sections of TSCC which suggested that newly growth nerves (namely neoneurogenesis) were observed in tumor mciroenvironment. The intensity of newly formed nerve bundles increased with T stage, and the difference was statistically significant between early stage (T1、T2) and late stage (T3、T4) (p=0.000). Increased prevalence of newly growth nerve bundles correlated significantly to the cervical lymph node metastasis (p=0.000). Conclusions: Neoneurogenesis in tumor microenviroment of TSCC is a predisposing factor to its aggressive development and cervical lymph node metastasis. From a therapeutic perspective, further studies on the topic may provide a new clinical opportunity through anti-neurogenesis.