The Correlation Between Depth of Invasion, and Degree of Differentiation with Cervical Lymph Node Metastasis in Oral Squamous Cell Carcinoma

Abstract

Objective: To study the significance of Depth of invasion (DOI), and the degree of differentiation (DOD) as predictors of cervical nodalmetastasis in oral squamous cell carcinoma. To determine a cut-off depth beyond which there is a high risk of cervical metastasis. Todetermine whether the DOI can be is alone enough as predictor for lymphatic metastasis despite the DOD. Methods: Forty-eight patients with OSCC were included in the study 28 males and 20 females ranging between 25 to 80 years. Alltreated in Ghazi Al-Hariri hospital for surgical specialties in Baghdad Medical city between 2017 to 2019. Slides were examined afterimmunohistochemical staining. Depth of invasion was measured according to the criteria of AJCC, and the WHO system of grading was, all histopathological parameters were recorded after immunohistochemical staining. Results: The depth of invasion ranged between 2 and 13 mm with a mean of 6.58 mm and SD of ± 2.56 mm and it was found to be ahighly significant predictor for lymphatic metastasis (P-value = 0.001), the cut-off point with a significant risk of metastasis was 5 mm. Thedegree of differentiation was also a significant predictor for cervical metastasis (P-value = 0.024) with poorly differentiated SCC carrying the highest risk of cervical metastasis despite the depth of the tumor invasion. Conclusion: DOI and DOD were significant histological parameters that predict the behavior of the well and moderately differentiated oral squamous cell carcinoma and hence the management of the neck in OSCC. However, the depth of invasion was not significance in cases of poorly differentiated OSCC. Therefore, we recommend that elective neck dissection should be done in cases of poorly differentiated OSCC despite the DOI.