Incidence of small lymph node metastases with evidence of extracapsular extension: clinical implications in patients with head and neck squamous cell carcinoma.
OBJECTIVE
Small lymph nodes (LN) show evidence of extracapsular extension (ECE) in a significant number of patients. This study was performed to determine the impact of ECE in LN ≤7 mm as compared with ECE in larger LN.


METHODS
All tumor-positive LN of 74 head and neck squamous cell carcinoma (HNSCC) patients with at least one ECE positive LN were analyzed retrospectively for the LN diameter and the extent of ECE. Clinical endpoints were regional relapse-free survival, distant metastasis-free survival, and overall survival. The median follow-up for the surviving patients was 2.1 years (range, 0.3-9.2 years).


RESULTS
Forty-four of 74 patients (60%) had at least one ECE positive LN ≤10 mm. These small ECE positive LN had a median diameter of 7 mm, which was used as a cutoff. Thirty patients (41%) had at least one ECE positive LN ≤7 mm. In both univariate and multivariate Cox regression analyses, the incidence of at least one ECE positive LN ≤7 mm was a statistically significant prognostic factor for decreased regional relapse-free survival (adjusted hazard ratio [HR]: 2.7, p = 0.03, 95% confidence interval [CI]: 1.1-6.4), distant metastasis-free survival (HR: 2.6, p = 0.04, 95% CI: 1.0-6.6), and overall survival (HR: 2.5, p = 0.03, 95% CI: 1.1-5.8).


CONCLUSIONS
The incidence of small ECE positive LN metastases is a significant prognostic factor in HNSCC patients. Small ECE positive LN may represent more invasive tumor biology and could be used as prognostic markers.
Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Switzerland.
Pirus
P
Ghadjar
Mathew
M
Simcock
Heide
H
Schreiber-Facklam
Yitzhak
Y
Zimmer
Ruth
R
Gräter
Christina
C
Evers
Andreas
A
Arnold
Ludwig
L
Wilkens
Daniel M
DM
Aebersold
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000556:secondary*; D016001:Confidence Intervals; D018572:Disease-Free Survival; D005260:Female; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009333:Neck; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging / Q000379:methods; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D012044:Regression Analysis; D012189:Retrospective Studies; D047368:Tumor Burden