Author(s)
Jose E. Alonso, MD
Thomas E. Heineman, MD
Edward C. Kuan, MD MBA
Maie A. St. John, MD PhD
Affiliation(s)
UCLA
Abstract:
Educational Objective: At the conclusion of this presentation, the participants should be able to discuss the pattern of cervical lymph node metastases and their prognostic impact in patients with lower gum squamous cell carcinoma. Objectives: To describe the pattern of cervical regional node metastases in lower gum squamous cell carcinoma (LGSCC) and assess their predictive performance in survival outcomes. Study Design: Retrospective, population based cohort of patients diagnosed with LGSCC between 1973-2015 via the Surveillance, Epidemiology, and End Results database. Methods: Univariate and multivariate analysis on pathologic lymph node data. Survival analysis was performed utilizing the Kaplan-Meier method. Results: A total of 4,285 cases of LGSCC were identified. Most cases presented with stage 1 (26.8%) and stage 2 (19.8%) disease, though a sizeable number of cases (32.8%) presented with stage 4. The median age at diagnosis was 71.0 years. Regional nodal disease was identified in 504 cases. Of these, the majority (83.5%) involved varying combinations of levels I-III, with level I (45.8%) and level I with level II (13.5%) most frequently affected. Less patients (14.2%) involved levels IV-V and retropharyngeal (RP) nodal levels, though patients with level IV alone (63.9%) and level V alone (22.2%) were observed more frequently. Regional metastases to levels I-III and/or levels IV-V, RP nodes independently predicted poorer OS [HR 1.005, 95% CI (1.004-1.007), p < 0.001; HR 1.009, 95% CI (1.006-1.012), p < 0.001], respectively. Conclusions: Regional nodal involvement in patients with LGSCC portends poorer OS and DSS. Most patients with nodal disease involved levels I-III, though level IV-V, and retropharyngeal involvement was not uncommon. Similarly, levels I-III and IV-V, RP as categories independently predicted inferior survival. We present the very first and largest analysis describing the distribution of affected nodal levels and their prognostic value in patients with LGSCC.