cN+pN0 disease does not portend a less favorable prognosis compared with cN0pN0 in patients with resected oral cavity squamous cell carcinoma

Prognostic Value of Lymph Node Yield, Lymph Node Density, and pN in Oral Cancer

OBJECTIVES

To investigate thresholds for lymph node yield (LNY), lymph node density (LND), and pN in patients with oral squamous cell carcinoma in relation to previous findings in the literature.

STUDY DESIGN

Retrospective register-based study.

SETTING

Copenhagen Oral Cavity Squamous Cell Carcinoma database.

METHODS

Appropriate thresholds for LNY, LND, and pN were determined by areas under the curve and subsequently subjected to multivariate analysis. Five-year overall survival and 3-year recurrence-free survival were determined by Kaplan-Meier survival curves.

RESULTS

In total, 413 patients diagnosed with oral squamous cell carcinoma were included. In the pN0 cohort, no superior/prognostic LNY cutoff values were detected. In the pN+ cohort, areas under the curve determined thresholds of LNY, LND, and pN to be 21 nodes, 5%, and 3 metastases, respectively. The 5-year overall survival was 52% for patients with LNY ≥21 vs 38% for patients with LNY <21 (hazard ratio [HR], 1.49; 95% CI, 1.05-2.11; P < .05), 60% for patients with LND ≤5% vs 38% for patients with LND >6% (HR, 1.63; 95% CI, 1.03-2.57; P < .05), and 43% for patients with pN <3 vs 26% for patients with pN ≥3 (HR, 1.40; 95% CI, 1.04-2.15; P < .05).

CONCLUSIONS

Increased nodal yield, decreased LND, and decreasing number of pN were associated with significantly improved survival outcomes. LNY might serve as a prognosticator of survival as well as a surgical quality indicator. LND may have implications as a tool in cancer staging and treatment planning.

cN+pN0 disease does not portend a less favorable prognosis compared with cN0pN0 in patients with resected oral cavity squamous cell carcinoma

Background

We compared the clinical outcomes of patients with oral cavity squamous cell carcinoma (OCSCC) with cN+pN0 versus cN0pN0 disease.

Methods

A total of 1309 OCSCC patients with pN0 disease were included. Of them, 1019 and 290 cases had cN0pN0 and cN+pN0 disease, respectively. For comparison purposes, we also examined 799 patients with pN+disease (cN0pN+/cN+pN+, n = 239/560). Subgroup analysis was performed in a propensity score‐matched cohort with cN0pN0 and cN+pN0 disease (n = 284 each).

Results

Compared with cN0pN0, patients with cN+pN0 had a higher prevalence of the following variables: betel chewing, pT3−4, depth ≥10 mm, perineural invasion, and treatment with surgery and adjuvant therapy. The prognosis of patients with cN+pN0 (mean: 52 nodes) and cN0pN0 (mean: 39 nodes) disease was similar both in the original cohort and after propensity score matching. However, the 5‐year outcomes were more favorable for cN+pN0/cN0pN0 compared with cN0pN+/cN+pN+ (local control, 88%/88%/83%/81%; neck control, 94%/93%/82%/76%; distant metastases, 4%/3%/13%/31%; disease‐free survival, 84%/83%/68%/52%; disease‐specific survival, 92%/92%/77%/57%; overall survival, 81%/82%/59%/42%; all p values <0.001; cN+pN0 versus cN0pN0, all p values >0.05). cN+pN0 disease (vs. cN0pN0) was not significantly associated with local control, neck control, distant metastases, and survivals either in univariable or multivariable analyses.

Conclusions

Despite a higher risk factor burden, the prognosis of patients with cN+pN0 disease did not differ from that of cases with cN0pN0. The higher nodal yield and the more frequent use of adjuvant therapy in cN+pN0 disease may explain the lack of significant differences in terms of neck control compared with cN0pN0 disease.