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The Laryngoscope
VC 2015 The American Laryngological,
Rhinological and Otological Society, Inc.
What is the Role of Sentinel Lymph Node Biopsy in
Early-Stage Oral Cavity Carcinoma?
Vikas Mehta, MD, MPH, FACS; Cherie-Ann Nathan, MD, FACS
BACKGROUND
Lymphatic spread in oral cavity squamous cell car-
cinoma (OSCC) remains a critical factor for staging,
treatment, and prognosis. Involvement of the regional
lymphatics portends approximately 50% decrease in sur-
vival. OSCC–cervical metastases remain common. Due
to the inaccuracy of the physical exam and imaging to
reliably detect occult disease, elective neck dissections
(ENDs) have become the standard of care for the major-
ity of clinically node-negative (cN0) patients. However,
many patients (55%–76%)1–3 with T1/2 cN0 OSCC dis-
ease will not have pathologically positive cervical metas-
tases, and are being subjected to overtreatment with
unnecessary morbidity by an END. Sentinel lymph node
biopsy (SLNB) has emerged as a powerful tool for
advancing minimally invasive surgical management of
many cancers. SLNB has been proven to be highly sensi-
tive, cost-effective, and beneficial to patient quality of
life. The data supporting the use of SLNB in early-stage
OSCC, a brief description of the SLNB method, and
recent technical advances are the focus of this article.
LITERATURE REVIEW
A prospective multi-institutional trial was con-
ducted with 25 institutions and 34 surgeons.1 The study
enrolled patients with newly diagnosed T1/T2 cN0
OSCC over 3 years. All patients underwent SLNB dur-
ing the primary resection followed by END. Of the 140
eligible patients, there were 52 T1 (37.1%) and 88 T2
lesions (62.9%). Forty-one patients (29%) had positive
nodes after sentinel lymph node (SLN) sectioning and
immunohistochemistry (IHC), with 21 having the SLN
as the sole positive node. Of the 106 negative SLNBs,
100 were classified as truly negative on final pathology
of the neck dissection (ND) specimen, which corre-
sponded to a 0.94 negative predictive value (NPV) (95%
confidence interval [CI]: 0.88-0.98). Step-sectioning and
IHC increased the NPV to 0.96, with T1 and T2 lesions
having an NPV of 1.0 and 0.94, respectively. The false-
negative rate (FNR) was 9.8% overall (four false nega-
tives out of 41 positives, Table I). With an overall NPV of
0.96 in a population of 30% with metastatic disease, a
negative SLNB would thus demonstrate a regional
recurrence in only 4% of patients. Of the 140 patients,
100 could have been spared END.
A recent meta-analysis of 26 studies looking at
SLNB for head and neck cancer combined 593 early-
stage (T1/2) OSCC patients who had undergone SLNB
and a concurrent END.3 The SLNB was positive in 177
patients (29.8%) and true negative in 408 patients
(68.8%). The overall sensitivity and NPV of SLNB in the
OSCC cohort were 94% (95% CI: 89–98%) and 96% (95%
CI: 93–99%), respectively (Table I). This included an
additional 38 OSCC patients with T3/4 patients
(n 5 631). There were only 12 patients (<2%) misclassi-
fied as N0 on SLNB who had a positive concurrent
END, with eight patients having early T1/T2 oral cavity
tumors and four patients with T3/T4 OSCC. A separate
analysis was done that included five studies, which
examined regional recurrence in oral cavity and oropha-
ryngeal SCC patients who did not receive END following
negative SLNB. There were 11 documented regional
recurrences from 200 total patients (5.5%) with a follow-
up of 2 years.
Once a positive SLN is identified, the finding has
both therapeutic and prognostic implications. A retro-
spective study of 109 cT1/T2 N0 OSCC patients with
positive SLNB from 15 centers was conducted.4 All
patients had subsequently undergone ND at the time of
the SLNB or within 3 weeks (I–III, 13%; I–IV, 23%; I–V,
64%) for a total of 122 ND specimens with additional
(1non-SLN) metastases in 42/122 (34.4%). In those
patients with 1non-SLN, 18/42 patients (42.9%) had
From the Department of Otolaryngology/Head and Neck Surgery,
Louisiana State University Health–Shreveport, Shreveport, Louisiana,
U.S.A.
Editor’s Note: This Manuscript was accepted for publication July
6, 2015.
The authors have no funding, financial relationships, or conflicts
of interest to disclose.
Send correspondence to Vikas Mehta, MD, Co-Director of Head
and Neck Surgical Oncology, Feist-Weiller Cancer Center, 1501 Kings
Highway, Rm 9-203, Shreveport, LA 71130.
E-mail:
DOI: 10.1002/lary.25541
Laryngoscope 126: January 2016 Mehta and Nathan: SNLB in Early-Stage Oral Cavity Carcinoma
Reprinted by permission of Laryngoscope. 2016; 126(1):9-10.
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