Total Number of Lymph Nodes in Neck Dissection and its Relation to Cancer-Positive Lymph Nodes as a Prognostic Indicator in Aerodigestive Tract Cancers

Abstract

<h3>Purpose/Objective(s)</h3> Few studies have been conducted on the total number of lymph nodes (LNs) in neck dissection and the lymph node ratio (LNR; number of positive LNs divided by number of excised LNs), or their potential use as a prognostic indicator for cancers of the upper aerodigestive tract (UADT) and its treatment. We aimed to measure the number of LNs dissected and the LNR to assess their prognostic value for cancers of the UADT, as well as their effect on overall survival and disease-free survival. <h3>Materials/Methods</h3> We performed a retrospective study of patients diagnosed with cancer of the UADT who underwent neck dissection as the primary or secondary modality of their treatment plan at King Abdulaziz University Hospital and the National Guard Hospital, Jeddah, Saudi Arabia. Data were collected through medical records and analyzed to assess prognosis and calculate survival rates in relation to the number of LNs and LNR. <h3>Results</h3> A total of 121 patients were included:14 women (11.57%) and 107 men (88.43%). The median age was 60 years and the mean follow-up period 2.7 years. Of the malignancies, 44.63%were of the oral tongue and 35.54% were laryngeal. A median of 38 LNs were dissected during neck dissections. The distribution of the individual LNRs was characterized by mean values. A mean LNR of 0.04 was considered the cutoff value, an LNR of >0.04 a high LNR, and an LNR of <0.04 a low LNR. Kaplan-Meier survival estimates for the cohort showeda3-year overall survival rate of 88% (95%confidence interval [CI]: 77% to 94%) for patients with a low LNR, but 71% (95% CI: 47% to 85%) for patients with a high LNR, which was statistically significant. A similar significant decreasing trend persisted at the 4-yearfollow-up, where the disease-free survival rate was 73% (95% CI: 61% to 82%) for patients with a low LNR compared with 56% (95% CI: 35% to 72%) for patients with a high LNR. <h3>Conclusion</h3> The number of excised LNs in neck dissections and the LNR might be a good prognostic indicator for overall survival and disease-free survival in patients with cancers of the UADT and may serve as a valuable tool in deciding on different treatment plans.