Radical Neck Dissection: (RND) Classification, Indication and

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Transcript Radical Neck Dissection: (RND) Classification, Indication and

Radical Neck Dissection: (RND)
Classification, Indication and
Techniques
Introduction
• Crile in 1906 introduced RND and is
followed by Martin as a the classical
procedure for the management of
cervical lymph node metastasis
• Recently changes in classification and
indication led to inconsistency
– N0 in recent studies may require selective
RND to reduce morbidity
Staging of Neck Nodes
• NX:
– Regional lymph nodes can not be assessed
• N0:
– No regional lymph node metastasis
• N1:
– Metastasis in a single ipsilateral lymph nodes,
3 cm or less in greatest dimension
• N2:
– N2a:
• Metastasis in a single epsilateral lymph nodes,
more than 3 cm but less than 6 cm
Staging of Neck Nodes
– N2b:
• Metastasis in multiple ipsilateral lymph
nodes, not more than 6 cm
– N2c:
• Metastasis in bilateral or contralateral
nodes not more than 6 cm in diameter
• N 3:
– Metastasis in lymph nodes more than 6
cm in in greatest diameter
Meyers & Eugene: Operative Otolaryngology. 1997
Lymph Node Regions
• Region I:
– Submental and submandibular
triangle
• Ia: Submental triangle:
– Bounded by the anterior belly of digastric
and the mylohyoid muscle deep
• Ib: Submandibular triangle:
– Formed by the anterior and posterior belly
of the digastric muscle and the body of the
mandible
Memorial Sloan-kettering Cancer center
Lymph Node Regions
• Region II – IV:
– Lymph nodes are associated with the
Internal Jugular Vein (IJV) within the
fibroadipose tissues that extend from
the posterior border of sternocledomastoid muscle (SCM) medial to
lateral border of the sternohyoid
muscle
Memorial Sloan-kettering Cancer center
Lymph Node Regions
• Region II:
– Upper third including upper jugular,
jugulodigastric and upper posterior cervical
nodes
– Bounded by the digastric muscle superiorly
and the hyoid bone or carotid bifurcation
inferiorly
• IIa:
– nodes anterior to Spinal Accessory Nerve (SAN)
• IIb:
– nodes posterior to Spinal Accessory Nerve (SAN)
Memorial Sloan-kettering Cancer center
Lymph Node Regions
• Region III:
– Middle third jugular nodes from the
carotid bifurcation to cricothyroid
notch or omohyoid muscle
• Region IV:
– Lower third jugular nodes from
omohyoid muscle superiorly to the
clavicle inferiorly
Memorial Sloan-kettering Cancer center
Lymph Node Regions
• Region V:
– Lymph nodes of the posterior triangle
along the lower half of the SAN and
the transverse cervical artery
– Bounded by the anterior border of the
trapezius posteriorly, the posterior
border of SCM anteriorly and the
clavicle inferiorly
Memorial Sloan-kettering Cancer center
Lymph Node Regions
• Region VI:
– Anterior compartment, lymph nodes
surrounding the midline visceral structures
that extend from the hyoid bone superiorly to
the suprasternal notch inferiorly
– The lateral boundary is the medial border of
the carotid sheath
– Perithyroid, paratracheal, and lymph nodes
around the recurrent laryngeal nerve
Memorial Sloan-kettering Cancer center
Classification
•
The RND is classified according to the
Academy’s Committee for Head & Neck
Surgery & Oncology into four major type:
1.
2.
3.
Radical Neck Dissection
(RND)
Modified Radical Neck Dissection (MRND)
Selective Neck Dissection (SND)
1.
2.
3.
4.
4.
Supraomohyoid
Posterolateral
Lateral
Anterior
Extended Radical Neck Dissection (ERND)
Classification
• Radical neck Dissection:
– Removing all lymphatic tissues in regions I V and include removal of SAN, SCM and IJV
• Modified radical neck dissection:
– Excision of all lymph nodes removed with
RND with preservation of one or more nonlymphatic structures, SAN, SCM and/or IJV
• Subtype I: Preserve SAN
• Subtype II: Preserve SAN & SJV
• Subtype III: preserve SAN, SJV and SCM
– Known as Functional neck dissection (Bocca)
Classification
• Selective Neck dissection:
– Any type of cervical lymphadenectomy
with preservation of one or more
lymph node groups
– Four subtype:
•
•
•
•
Supraomohyoid neck dissection
Posterolateral neck dissection
Lateral neck dissection
Anterior neck dissection
Classification
– Supraomohyoid neck dissection:
• Removal of lymph nodes in regions I –III
• The posterior limit is the cutaneous branches of the
cervical plexus and posterior border of SCM
• The inferior limit is the superior belly of the
omohyoid where it cross IJN
– Posterolateral neck dissection
• Removal of suboccipital, retroauricular, levels II –
V and level V
• Subtyped I – III depending on the preservation of
SAN, IJV and /or SCM
Medina
Classification
– Lateral neck dissection:
• Remove lymph nodes in levels II – IV
– Anterior neck dissection:
• Require the removal of the lymph nodes
surrounding the visceral structure in the
anterior aspect of the neck, level VI
• Superior limit, hyoid bone
• Inferior limit, suprasternal notch
• Laterally, the carotid sheath
Classification
• Extended neck dissection:
– Any previous dissection and including
one or more additional lymph node
groups and/or non-lymphatic tissues
Facts
• General nodal metastasis produce
the following fact:
– The most important factor in prognosis
of SCC of the upper aero-digestive
tract is the status of cervical lymph
nodes
– Cure rate drops 50% with involvement
of the regional lymph nodes
Indications For ND
• Radical neck dissection was believed by
Martin to be the only method to control
cervical lymphadenectomy
• Anderson found that preservation of SAN
did not change the survival or tumor
control in the neck
– Actual 5-year survival and neck failure rate
is:
• RND: 63% and 12 %
• MRND: 71% and 12%
Indications
•
Radical Neck Dissection
1.
Multiple clinically obvious cervical lymph
node metastasis particularly of posterior
triangle and closely related to SAN
2.
Large metastatic tumor mass or multiple
matted in upper part of the neck
•
Tumor should not be dissected to preserve
Structures
Indications
•
Modified radical neck dissection
–
MRND Type I:
1. Clinically obvious neck lymph nodes
metastasis and SAN not involved by
tumor
2. Intraoperative decision just like
preservation of the facial nerve in
parotid surgery
Indications
•
MRND Type II:
1.
2.
•
Rarely planned
Intra-operative decision for tumor found
adherent to SCM but away from SAN &
IJV
MRND Type III:
–
Depend on the autopsy reports
1.
2.
Lymph nodes were in the fibrofatty and do not
share the same adventitia with blood vessels
They are not found within the aponeurosis or
glandular capsule of the submandibular
“Functional neck dissection”
Indications
• MRND Type III:
– For treatment of N0 neck nodes
– Indicated for N1 mobile nodes and not
greater than 2.5 – 3.0 cm
• Contra-indicated in the presence of node
fixation
• Result is difficult to interpret because of
the use of radiation therapy
Indications
• Selective/elective neck dissection:
– For treatment of N0 neck nodes
– For N+ nodes when combined with
radiotherapy
• Adjuvant radiotherapy for patient with 2 – 4 positive
nodes or extra-capsular spread
– Supraomohyoid is indicated for SCC of oral
cavity with N0 and N1 with palpable mobile
nodes less than 3 cm and located in level I and
II
– Upgrade intra-operatively following positive
frozen section
Treatment option for N0 nodes
• Observe
• Radiation therapy
• Elective neck dissection
– Low morbidity
– Staging neck for possible extended
surgery
– Need for post-operative radiotherapy
Rationale for S/END
• Rate of occult metastasis in clinically
negative nodes is 20 – 30% using
clinical and radiographic findings
– Ct scan combined with physical exam
decreased the rate of occult metastasis
to 12%
– This suggested lowering of the criteria
for elective neck dissection
Friedman et al Laryngoscope 100; 54 – 59: 1990
Rationale for S/END
• Anatomic studies showed that
lymphatic drainage from the
mucosal surfaces follow a constant
and predictable route
• Lymph flow from SA chain to the
jugular chain is unilateral
Shah. Ann Surg Oncol 1(6); 521-532: 1994
Rationale for S/END
• Shah, in his study produced a compelling
evidence of predictable nodal metastasis
from SCC from upper aerodigastive tract
– He found a specific pattern for nodal spread
by location of primary
• NO in patients with oral cavity SCC:
– 7/1119 (3.5%) had nodal involvement outside
supraomohyoid dissection
– 3 (1.5%) had isolated involvement outside level
I - III
Friedman Laryngoscope 100; 54-59: 1990
Rationale for S/END
– N+ nodes in patients with oral SCC:
• 50/246 had nodal metastasis outside level IV
• 10/246 had metastasis in level V
– He examined nodal involvement in patients
with nasopharynx and other upper parts of the
aerodigastive tract
• Conclusion:
– SCC of the oral cavity:
• Level I, II and III are at risk
– SCC nasopharynx and larynx
• Level II, III and IV are at risk
Shah Amer J Surg 160; 405-409: 1990
Shah Cancer July 1 ; 109-113: 1990
Rationale for S/END
• Byers stated that SND combined with
postoperative radiotherapy in selected
patients with oral cavity SCC was adequate
treatment with similar recurrence rate as
those treated with MRND III
• Spiro reported 12% with supraomohyoid
dissection in N1 nodes but not all of them
received radiotherapy
Byers Head Neck Surg; Jan-Feb; 160-167: 1988
Selective/Elective Neck
Dissection
• A good option for N0 neck
• Not a suitable option for N+ neck
• Is used N+ neck when combined
with radiotherapy
• Intra-operative frozen section
evaluation is needed to confirm in
cases of intraoperative palpable
nodes
The anatomy
• Skin:
– Blood supply:
• Descending branches:
– The facial
– The submental
– Occipital
• Ascending branches
– Transverse cervical
– Suprascapular
– The branches perforate the platysma muscle, anastomose to
form superficial vertically-directed network of vessels
• Skin incision is superiorly based apron-like incision
from mastoid to mentum or to contralateral mastoid
The anatomy
• Platysma muscle:
– Wide, quadrangular sheet-like muscle
– Run obliquely from the upper part of the
chest to lower face
– Skin flap is raised immediately deep to the
muscle
– The posterior border is over or just anterior
to IJV and great auricular nerve
– Does not cover the inferior part of the
anterior triangle and the posterolateral neck
The anatomy
• Sternocleidomastoid muscle: SCM
– Differentiated from the platysma by the
direction of its fibres
– Crossed by the IJV and the great
auricular nerve from inferior to
posterior deep to platysma
– The posterior border represent the
posterior boundary of nodes level II - IV
The anatomy
• Marginal Mandibular nerve: MMN
– Located 1 cm in front of and below
the angle of the mandible
– Deep to the superficial layer of the
deep cervical fascia
– Superficial to adventitia of the anterior
facial vein
The anatomy
• Spinal Accessory nerve: SAN
– Emerge from the jugular foramen medial to
the digastric and stylohyoid muscles and
lateral and posterior to IJV (30% medial to
the vein and in 3 -5% split the nerve)
– It passes obliquely downward and backward
to reach the medial surface of the SCM near
the junction of its superior and middle thirds,
Erb’s point
The anatomy
• Trapezius muscle:
– Its anterior border is the posterior
boundary of level V
– Difficult to identify because of its
superficial position
– Dissect superficial to the fascia in order
to preserve the cervical nerves
The anatomy
• Digastric Muscle; Posterior belly:
– Originate from a groove in the mastoid
process, digastric ridge
– The marginal mandibular nerve lie
superficial
– The external and internal carotid
artery, hypoglossal and 11th cranial
nerves and the IJV lie medial
The anatomy
• Omohyoid muscle:
– Made of two bellies, and is the
anatomic separation of nodal levels III
and IV
– The posterior belly is superficial to the
brachial plexus, phrenic nerve and
transverse cervical artery and vein
– The anterior belly is superficial to the
IJV
The anatomy
• Brachial Plexus & Phrenic nerve:
– The plexus exit between the anterior
and middle scalene muscles, pass
inferiorly deep to the clavicle under the
posterior belly of the omohyoid
– The phrenic nerve lie on top of the
anterior scalene muscle and receive it
is cervical supply from C3 – C5
The anatomy
• Thoracic duct:
– Located in the lower let neck posterior
to the jugular vein and anterior to
phrenic nerve and transverse cervical
artery
– Have a very thin wall and should be
handled gently to avoid avulsion or
tear leading to chyle leak
The anatomy
• Exit via the hypoglossal canal near the
jugular foramen
• Passes deep to the IJV and over the ICA
and ECA and then deep and inferior to
the digastric muscle and enveloped by a
venous plexus, the ranine veins
• Pass deep to the fascia of the floor of the
submandibular triangle before entering
the tongue
Summary
• Unified classification is relatively new
• Indication and the type of ND, specially for N0,
is controversial
• The following surgical outline was suggested:
– SCC oral cavity anterior to circumvalate papilla
• Supraomohyoid
– SCC Oropharynx, larynx and hypopharynx
• level I- IV or level II-V
– SCC with N+ nodes
• RND
– SCC with 2-4 positive nodes or extracapsular spread
• RND and adjuvant therapy
Shah Cancer July 1;109-113: 1990