Quantification of lymph nodes in the central compartment of the neck: a cadaveric study

Abstract

Differentiated thyroid cancer (DTC) accounts for over 90 % of thyroid malignancies, and is frequently associated with central neck compartment nodal metastasis that requires a therapeutic central compartment neck dissection (CCND) for clinically evident nodes. Current knowledge on the expected lymph node yield from a CCND is limited, compared with data on the lateral neck. The aim of our study was to accurately quantify nodal yield from the cadaveric central neck compartment. Twenty-eight cadaveric necks were dissected and the central neck compartment was subdivided into four regions: pre-laryngeal (delphian), pre-tracheal, right and left para-tracheal regions. Each cadaver had a thyroid gland, which was also removed, and the CCND tissue in each compartment was processed and examined by a consultant histopathologist. Only lymphoid tissue with a defined microscopic fibrous capsule and subcapsular sinus was included in the node count. The median total lymph node count per cadaver was four (range 1–16), with a median of one node detectable in each para-tracheal region (range 0–7) and the pre-tracheal region (range 0–8). The median pre-laryngeal node count was 0 (range 0– 2). The average lymph node size across all compartments was 2.9 mm. This is the first European study to assess cadaveric central neck lymph nodes and establish baseline counts for nodal yield. If a prophylactic or therapeutic CCND is required during thyroid surgery, those involved in DTC management must recognise that there is a wide range, and low median yield of central neck compartment lymph nodes.

Full text

HEAD AND NECK
Quantification of lymph nodes in the central compartment
of the neck: a cadaveric study
Enyinnaya Ofo
1
•Selvam Thavaraj
2
•Daron Cope
1
•James Barr
1
•
Karan Kapoor
1
•Jean-Pierre Jeannon
1
•Richard Oakley
1
•Claire Lock
2
•
Edward Odell
2
•Ricard Simo
1
Received: 2 August 2015 / Accepted: 29 October 2015 / Published online: 20 November 2015
ÓSpringer-Verlag Berlin Heidelberg 2015
Abstract Differentiated thyroid cancer (DTC) accounts
for over 90 % of thyroid malignancies, and is frequently
associated with central neck compartment nodal metastasis
that requires a therapeutic central compartment neck dis-
section (CCND) for clinically evident nodes. Current
knowledge on the expected lymph node yield from a CCND
is limited, compared with data on the lateral neck. The aim of
our study was to accurately quantify nodal yield from the
cadaveric central neck compartment. Twenty-eight cadav-
eric necks were dissected and the central neck compartment
was subdivided into four regions: pre-laryngeal (delphian),
pre-tracheal, right and left para-tracheal regions. Each
cadaver had a thyroid gland, which was also removed, and
the CCND tissue in each compartment was processed and
examined by a consultant histopathologist. Only lymphoid
tissue with a defined microscopic fibrous capsule and sub-
capsular sinus was included in the node count. The median
total lymph node count per cadaver was four (range 1–16),
with a median of one node detectable in each para-tracheal
region (range 0–7) and the pre-tracheal region (range 0–8).
The median pre-laryngeal node count was 0 (range 0– 2). The
average lymph node size across all compartments was
2.9 mm. This is the first European study to assess cadaveric
central neck lymph nodes and establish baseline counts for
nodal yield. If a prophylactic or therapeutic CCND is
required during thyroid surgery, those involved in DTC
management must recognise that there is a wide range, and
low median yield of central neck compartment lymph nodes.
Keywords Central neck dissection Lymph node yield 
Cadaver Thyroidectomy Pathology Thyroid cancer
Introduction
Differentiated thyroid cancer (DTC) accounts for over
90 % of thyroid malignancies for which over 80 % are
papillary thyroid carcinoma (PTC) [1,2]. The central neck
lymph node compartment is frequently involved with
microscopic metastatic PTC in over 40 % of clinically
node negative (cN0) cases [3], and in the presence of
clinically evident nodal disease (cN1), a therapeutic central
compartment neck dissection (CCND) is advocated to
improve loco-regional control [4]. Despite the high
propensity for subclinical nodal metastasis in PTC, its
impact on survival remains controversial [5], and the role
of prophylactic CCND continues to be extensively debated
[6]. Some authors have shown no oncological benefit for
prophylactic CCND [7–10], and the increased rate of
complications, such as permanent hypoparathyroidism, are
highlighted as reasons to avoid the procedure [11]. Con-
versely, other investigators have advocated prophylactic
CCND to help predict prognosis and guide appropriate
postoperative radioactive iodine ablation [12–16], whilst
also reporting lower rates of loco-regional recurrence in
cN0 DTC patients undergoing CCND [17,18].
Results of this paper were presented at the British Association of
Endocrine and Thyroid Surgeons (BAETS) 2013 annual meeting, and
the IFHNOS 5th World Congress/American Head and Neck Society
2014 annual meeting.
&Enyinnaya Ofo
eofo@hotmail.com
1
Department of Otolaryngology, Head & Neck Surgery, Guy’s
and St Thomas’ NHS Foundation Trust, Great Maze Pond,
London SE1 9RT, United Kingdom
2
Department of Head and Neck Pathology, Guy’s and St
Thomas’ NHS Foundation Trust, Great Maze Pond,
London SE1 9RT, United Kingdom
123
Eur Arch Otorhinolaryngol (2016) 273:2773–2778
DOI 10.1007/s00405-015-3827-y
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