2018-19 Section 7-Neoplastic and Inflammatory Diseases of the Head and Neck eBook

Original Article

TABLE 2. Summary of HRs for Number of Positive LNs and Number of LNs Examined Stratified by Changepoint

Multivariable Survival Analysis

Univariate Survival Analysis

Characteristics

HR*

95% CI

P

HR*

95% CI

P

No. of positive metastatic LNs a 4

1.483 1.018

1.417-1.552 1.013-1.022

< .001 < .001

1.337 1.020

1.267-1.410 1.014-1.025

< .001 < .001

> 4

No. of LNs examined b 33

1.012 1.014

1.003-1.021 1.008-1.019

.009

0.988 1.003

0.979-0.998 0.996-1.010

.017 .354

> 33

< .001

Abbreviations: 95% CI, 95% confidence interval; HR, hazard ratio; LN, lymph node. *Hazard ratio expressed as 1 unit increment

a Multivariable model was stratified based on grade and radiotherapy and adjusted for age, comorbidity, facility type, insurance, histology, T classification, sur- gical margins, chemotherapy, and positive regional LNs with 4 knots at the 5th, 35th, 65th, and 95th quantiles (1, 2, 6, and 37 LNs, respectively). b Multivariable model was stratified based on grade and radiotherapy and adjusted for age, comorbidity, facility type, insurance, histology, T classification, sur- gical margins, chemotherapy, and regional LNs examined with 3 knots at the 10th, 50th, and 90th quantiles (11, 26, and 52 LNs, respectively).

Figure 2. Defining a novel lymph node (LN) staging system for salivary gland cancer in patients with determinable American Joint Committee on Cancer (AJCC) eighth edition stage, using recursive partitioning analysis based on the number of positive lymph nodes. 1 indicates positive; -, negative; ENE, extranodal extension; OS, overall survival.

Cancer

6