Prognostic Significance of Lymph Node Ratio in Predicting the Outcome of Oral Squamous Cell Carcinoma - A Retrospective Study.

ABSTRACT

Introduction: The lymph node status is a very important prognostic factor in head-and-neck cancer. The presence of metastatic lymph nodes will reduce the overall survival by 50%. Lymph node ratio (LNR) is defined as the ratio of the number of positive lymph nodes to the total number of lymph nodes dissected. The aim of the study was to investigate the prognostic value of LNR in oral squamous cell carcinoma (OSCC). Materials and Methods: Medical records of pathologically confirmed OSCC patients who reported with loco-regional recurrence from January 2017 to January 2022 were analysed. LNR and disease-free survival (DFS) were calculated for each patient. The endpoint of the study was disease-free survival. Spearman's correlation was used to establish a correlation between DFS and LNR. Results: A total of 33 patients were included in the study. DFS was calculated for all the patients. LNR was calculated in patients with pathological N+ neck. There was a negative significant moderate correlation between LNR and DFS (Spearman's rho = -0.593, P < 0.001). A higher LNR value of more than 0.01 was associated with a shorter DFS period. T4 tumour stage had significantly higher LNR. A positive significant moderate correlation was found between LNR and tumour stage (Spearman's rho = 0.703, P = 0.01). As the T stage increased, the LNR ratio also increased. In the present study, tumour subsite tongue was associated with significantly higher LNR (P = 0.001). Discussion: LNR can be considered an independent prognostic parameter for DFS in OSCC patients with cervical lymph node metastasis.