Laryngeal Cancer Flashcards
What are the three divisions of the larynx?
supraglottis
glottis
subglottis
supraglottis (anatomy)(5)
aryepiglottic folds arytenoids, epiglottis (supra and infra), false vocal cords, ventricles (sometimes pharyngoepiglottic folds)
glottis (anatomy)(4)
anterior commissure,
floor of the ventricle, interarytenoid area (posterior commissure),
true vocal cords
What is the axial line of demarcation between the supraglottic and the glottic larynx?
apex of the ventricle
Describe the position of the subglottis anatomically.
The demarcation between the glottis and subglottis is ill-defined.
It is usually considered to extend from a point 5 mm below the free margin of the vocal cord to the inferior border cricoid cartilage or
10 mm below the apex of the ventricle.
What is the only complete ring of the upper airway?
Cricoid cartilage
Which group of muscles primarily control the movement of the cords?
Intrinsic muscles
Which group of muscles are concerned primarily with swallowing?
Extrinsic muscles
What muscle draws the larynx anteriorly and inferiorly when contracting resulting to an increased pitch of voice?
Cricothyroid muscle
What is the innervation of the intrinsic muscles of the larynx?
Recurrent laryngeal nerve
What is the innervation of the cricothyroid muslce?
Superior laryngeal nerve
The preepiglottic and paraglottic fat spaces are essentially one contiguous space lying between the external framework of the thyroid cartilage and hyoid bone and the inner framework of the epiglottis and intrinsic muscles.
TRUE or FALSE?
True
Because of the abundance of capillary lymphatics arise in the preepiglottic and paraglottic area, invasion of the fat space seldom often leads to lymph node metastases, in contrast to the glottic area which essentially has very limited lymphatics.
False.
Because few capillary lymphatics arise in this area, invasion of the fat space seldom leads to lymph node metastases.
Boundaries of the fat space
anterior/lateral
inferior
superior
medial
inferiorly-conus elasticus
anterolaterally- thyroid ala, thyrohyoid membrane, quadrangular membrane, hyoid
superiorly- hyoepiglottic ligament
medial- fascia of the intrinsic muscles
What is the histology of the laryngeal surface of the epiglottis and the free margins of the vocal cords?
How about the remaining mucosa?
squamous epithelium
pseudostratified ciliated columnar epithelium
Where do branches of laryngeal arteries come from?
superior and inferior thyroid arteries
The supraglottic structures have a rich capillary plexus; the trunks pass through the preepiglottic space and thyrohyoid membrane.
TRUE or FALSE?
True
The subglottic area has relatively few capillary lymphatics. The lymphatic
trunks pass through the cricothyroid membrane to the pretracheal (delphian)
lymph nodes in the region of the thyroid isthmus. The subglottic area also drains
posteriorly through the cricotracheal membrane, with some trunks going to the
paratracheal (level VI) lymph nodes and others continuing to the inferior jugular
(level IV) chain.
TRUE or FALSE?
True
Laryngeal is the most common head and neck mucosal cancer.
TRUE or FALSE?
False.
2nd most common
Glottic carcinoma is more common than supraglottic carcinoma.
TRUE or FALSE?
True.
2:1
What is the most commonly implicated etiology in the development of laryngeal cancer?
Cigarette smoking.
The risk of
tobacco-related cancers of the upper alimentary and respiratory tracts declines
among former smokers after __ years and is said to approach the risk of
nonsmokers after __ years of abstention.
5 and 10 respectively.
Where is the most common site of glottic cancer?
anterior portion of the cord
Involvement of the cords on their external surface occurs early,
submucosal extension by the way of the paraglottic space occurs later.
TRUE or FALSE?
False.
Vice-versa
Thyroid cartilage invasion usually occurs in the ossified section of the cartilage.
TRUE or FALSE?
True.
commonly in the region of the anterior commissure tendon or the junction of the anterior1/4 and posterior 3/4 of the thyroid lamina.
Causes of vocal cord fixation
invasion or destruction of the vocal cord muscle,
invasion of the cricoarytenoid muscle or joint
invasion of the RLN (rarely)
Perineural spread is common in laryngeal cancers.
TRUE or FALSE?
False.
It is uncommon.
Tumors of the infrahyoid epiglottis involve the valeculla and base of tongue only through the involvement of suprahyoid epiglottis.
TRUE or FALSE?
False.
tumor may present in the vallecula and base of tongue without
involving the suprahyoid epiglottis
Which subsite of the larynx is most rarely involved, and if involved is difficult to know whether it originated from there or just an extension?
Subglottic larynx
Supraglottic SCC and glottic tumors mainly spread through the lymphatics via which nodal level?
Level II
Anterior commissure and
anterior subglottic invasion are also associated with involvement of the which nodes?
midline pretracheal lymph node (level VI)
Most common symptom of early true vocal cord cancer?
Hoarseness
Most frequent initial symptom of supraglottic cancer?
Odynophagia
First “sign” of supraglottic cancer
Neck mass
How to determine vocal cord mobility in fiber-optic examination of the vocal cords?
Ask the patient to say "ee" (adduction) and sniff (abduction)
In fiberoptic examination, what is/are indirect sign/s of preepiglottic space invasion?
ulceration of infrahyoid epiglottis
fullness of the vallecula
Why is CT scan preferred over MRI in the imaging of laryngeal cancer?
MRI scanning time is longer which produces motion artifact.
AJCC 2017 (8th ed)
Staging: Supraglottic
T1
Tumor limited to one subsite of supraglottis with normal vocal cord mobility
AJCC 2017 (8th ed)
Staging: Supraglottic
T2
Tumor invades mucosa of more than one adjacent subsite of the supraglottis or glottis or region outside the supraglottis (e.g., mucosa of the base of the tongue, vallecula, medial wall of the pyriform sinus) without fixation of the larynx
AJCC 2017 (8th ed)
Staging: Supraglottic
T3
Tumor is limited to the larynx with vocal cord fixation and/or invades any of the following area: postcricoid space, preepiglottic space, paraglottic space, and/or inner cortex of the thyroid cartilage
AJCC 2017 (8th ed)
Staging: Supraglottic
T4a and T4b
A. Moderately advanced local disease; tumor invades through the thyroid cartilage and/or invades tissue beyond the larynx (e.g., trachea, soft tissues of the neck including deep extrinsic muscles of the tongue, strap muscles, thyroid, or esophagus)
B. Very advanced local disease; tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures
AJCC 2017 (8th ed)
Staging: Glottic
T1a and b
Tumor limited to the vocal cord(s) (may involve the anterior or posterior commissure) with normal mobility
A. Tumor limited to one vocal cord
B. Tumor involves both vocal cords.
AJCC 2017 (8th ed)
Staging: Glottic
T2
Tumor extends to the supraglottis and/or subglottis with impaired vocal cord mobility.
AJCC 2017 (8th ed)
Staging: Glottic
T3
Tumor limited to the larynx with vocal cord fixation and/or invasion of paraglottic space and/or inner cortex of the thyroid cartilage
AJCC 2017 (8th ed)
Staging: Glottic
T4a and T4b
A. Moderately advanced local disease; tumor invades through the outer cortex of the thyroid cartilage and/or invades tissue beyond the larynx (e.g., trachea, soft tissues of the neck including deep extrinsic muscles of the tongue, strap muscles, thyroid, or esophagus)
B. Very advanced local disease; tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures
AJCC 2017 (8th ed)
Staging: Subglottic
T1
Tumor limited to the subglottis
AJCC 2017 (8th ed)
Staging: Subglottic
T2
Tumor extends to vocal cord(s) with normal mobility
AJCC 2017 (8th ed)
Staging: Subglottic
T3
Tumor limited to larynx with vocal cord fixation and/or inner cortex of the thyroid cartilage
AJCC 2017 (8th ed)
Staging: Subglottic
T4a and T4b
A. Moderately advanced local disease; tumor invades cricoid or thyroid cartilage and/or invades tissue beyond the larynx (e.g., trachea, soft tissues of the neck including deep extrinsic muscles of the tongue, strap muscles, thyroid, or esophagus)
B. Very advanced local disease; tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures
AJCC 2017 (8th ed) Staging: Recite Clinical Regional Nodes definition for Laryngeal Ca
(same for oropharynx p16-, and hypopharynx)
N1-Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE(–)
N2A-Metastasis in a single ipsilateral node, larger than 3 cm but not larger than 6 cm in greatest dimension and ENE(–)
N2B-Metastasis in a multiple ipsilateral nodes, none larger than 6 cm in greatest dimension and ENE(–)
N2C-Metastasis in a bilateral or contralateral lymph nodes, none larger than 6 cm in greatest dimension and ENE(–)
N3A-Metastasis in a lymph node larger than 6 cm in greatest dimension and ENE(–)
N3B-Metastasis in any node(s) and clinically overt ENE(+)
AJCC 2017 (8th ed) Staging: Recite Pathologic Regional Nodes definition for Laryngeal Ca
(same for oropharynx p16-, and hypopharynx)
N1-Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE(–)
N2A-Metastasis in a single ipsilateral node, 3 cm or smaller in greatest dimension and ENE(+)
or
a single ipsilateral node larger than 3 cm but not larger than 6 cm in greatest dimension and ENE(–)
N2B-Metastasis in a multiple ipsilateral nodes, none larger than 6 cm in greatest dimension and ENE(–)
N2C-Metastasis in a bilateral or contralateral lymph nodes, none larger than 6 cm in greatest dimension and ENE(–)
N3A-Metastasis in a lymph node larger than 6 cm in greatest dimension and ENE(–)
N3B-Metastasis in a single ipsilateral node larger than 3 cm in greatest dimension and ENE(+)
or
multiple ipsilateral, contralateral, or bilateral nodes, any with ENE(+)
AJCC 2017 (8th ed) Staging:
STAGE 1
T1 N0
AJCC 2017 (8th ed) Staging:
STAGE 2
T2 N0
AJCC 2017 (8th ed) Staging:
STAGE 3
T3 N0
T3 N1
T1 N1
T2 N1
AJCC 2017 (8th ed) Staging:
STAGE 4A
T4a N0-2
T1 N2
T2 N2
T3 N2
AJCC 2017 (8th ed) Staging:
STAGE 4B
T4b ANY N
ANY T, N3
AJCC 2017 (8th ed) Staging:
STAGE 4C
M+
What is the most common histology of laryngeal cancer?
SCC
What area of the larynx is carcinoma in situ most common?
vocal cords
Most vocal cord carcinomas are poorly-differentiated.
TRUE or FALSE?
False.
Most are well to moderately differentiated.
What is the major determinant of LC (local control)?
T-stage
What is the major determinant of LRC (local-regional control)?
overall AJCC stage (T&N)
What is the major determinant of CSS (cause-specific survival)?
AJCC stage and N stage
Which has a better prognosis in general?
Men or women?
Women
General treatment options:
Carcinoma in situ
Transoral laser microsurgery
or
Early RT
General treatment options:
T1/T2
early vocal cord carcinoma
RT alone or TLM or TORS
What is the major advantage of RT compared with partial laryngectomy for vocal cord carcinoma?
Better quality of voice.
General treatment options:
Favorable T3 lesions
vocal cord carcinoma
RT (preferrably altered fractionation)
with salvage surgery
or
immediate total laryngectomy
sometimes extended hemilaryngectomy for well-lateralized fixed cord lesions.
Follow-up schedules after T3 definitive treatment
vocal cord carcinoma
Every 4-6 weeks (1) Every 6-8 weeks (2) every 3 months (3) every 6 months (4-5) annually thereafter
General treatment options:
advanced vocal cord carcinoma
total laryngectomy with or without PORT
What are the most frequent sites of local failure after total laryngectomy?
(vocal cord carcinoma)
tracheal stoma,
base of the tongue,
neck nodes,
soft tissues of the neck
Can neck dissection be withheld during laryngectomy for advanced laryngeal cancer with clinically negative neck ?
(vocal cord carcinoma)
Yes. If PORT is planned.
However, most surgeons perform it
General treatment options:
advanced vocal cord carcinoma
indications for PORT?
(vocal cord carcinoma)
-close or positive margins,
-significant subglottic extension (1 cm or more),
-cartilage invasion,
-perineural
invasion,
-lymphovascular space invasion,
-extension of the primary tumor into the soft tissues of the neck,
-multiple positive neck nodes, and
-extracapsular
extension
General treatment options:
advanced vocal cord carcinoma
Indications for definitive RT?
Definitive RT is prescribed for the patient who refuses total laryngectomy or is medically unsuitable for major surgery.
Vocal cord cancer, surgical treatment.
Contraindications for hemilaryngectomy
Tumor extension to the
epiglottis, false cord, or both arytenoids is a contraindication to
hemilaryngectomy.
Partial fixation of one cord is not a contraindication to
hemilaryngectomy; a few surgeons perform a hemilaryngectomy for selected
fixed-cord lesions.
RT techniques for T1-2 vocal cord carcinoma:
The field covers the primary lesion and elective nodal chains.
TRUE or FALSE?
False
The field covers only the primary lesion.
The neck nodes are not “electively” treated.
RT techniques for T1-2 vocal cord carcinoma:
Field borders for T1 lesions
superiorly from the thyroid notch
to the inferior border of the cricoid and fall of anteriorly
posterior (depends on tumor extension) usually 1 cm posterior to the back edge of the thyroid cartilage
RT techniques for T1-2 vocal cord carcinoma:
Field borders for T2 lesions
Same as T1 with adjustments depending on the anatomic distribution of the tumor.
RT techniques for T1-2 vocal cord carcinoma:
Larger field sizes increase the risk of laryngeal edema without improving the cure rate.
TRUE or FALSE?
True
RT techniques for T1-2 vocal cord carcinoma:
Commonly used total dose for conventional fractionation.
T1?
T2?
T1 - 66 Gy
T2 - 70 Gy
RT techniques for T1-2 vocal cord carcinoma:
1.8 Gy once daily results in significantly lower control than 2.0 Gy once daily.
TRUE or FALSE?
True
under Radiation Therapy techniques
RT techniques for T1-2 N0 vocal cord carcinoma:
2.25 Gy once daily results in significantly lower control and without difference in acute and late toxicity than 2.0 Gy once daily.
TRUE or FALSE?
False.
Yamakazi et al. reported a prospective trial in which patients with T1 N0
squamous cell carcinoma of the glottic larynx were randomized to definitive RT
at 2.0 Gy per fraction or 2.25 Gy per fraction. The 5-year local control rates were
77% after 2.0 Gy per fraction and 92% after 2.25 Gy per fraction (P = .004); there
was no difference in either acute or late toxicity.
RT techniques for T1-2 vocal cord carcinoma:
Field borders for T3-4 lesions
Superior - just above the angle of the mandible (includes level II)
Posterior - a portion of the spinal cord must be included to ensure level III coverage
lower border - bottom of cricoid cartilage, if no subglottic extension, slanted to be matched to the low-neck field
Enumerate the treatment arms in RTOG 90-03.
- Standard fractionation: 2 Gy per fraction, once a day, 5 days a week, to a total
dose of 70 Gy in 35 fractions over 7 weeks - Hyperfractionation: 1.2 Gy per fraction, twice daily (≥6 hours apart), 5 days a
week, to a total dose of 81.6 Gy in 68 fractions over 7 weeks - Accelerated fractionation with split: 1.6 Gy per fraction, twice daily (≥6 hours
apart), 5 days a week, to a total dose of 67.2 Gy in 42 fractions over 6 weeks,
including a 2-week rest after 38.4 Gy - Accelerated fractionation with concomitant boost: 1.8 Gy per fraction, once a
day, 5 days a week to a large field, plus 1.5 Gy per fraction once a day to a
boost field given 6 or more hours after treatment of the large field for the last
12 treatments days, to a total dose of 72 Gy in 42 fractions over 6 weeks
What are the results of RTOG 90-03?
The 5-year local–regional failure rates were as follows: standard fractionation,
59%; hyperfractionation, 51%; accelerated split course, 58%; and concomitant
boost, 52%. Both the hyperfractionation and concomitant schedules boost
yielded local–regional control rates that were significantly better than those with
standard fractionation. There was a trend toward improved overall survival with
hyperfractionation but no difference in cause-specific survival. Acute toxicity
was increased with all three altered fractionation schedules; there was a modest
increase in late effects with the concomitant boost schedule.
RT rarely cures vocal cord carcinoma patients with recurrence in the neck or stoma
after total laryngectomy.
TRUE or FALSE?
True
General Management for Early and Moderately Advanced Supraglottic Lesions
RT
or
Supraglottic laryngectomy +/- RT
(TLM/TORS for small)
(total layngectomy is rare)
When do you favor supraglottic laryngectomy over RT for early and moderately advanced supraglottic cancers?
infiltrative, large, bulky lesions >6cc especially with extensive preepiglottic space invasion
(preepiglottic space invsion is not a contraindiction to supraglottic laryngectomy and/or RT)
General Management for Early and Moderately Advanced Supraglottic Lesions:
early-stage primary but advanced neck disease (N2b or N3)
primary - definitive RT/supraglottic laryngectomy
involved neck - surgery
no PORT?
General Management for Early and Moderately Advanced Supraglottic Lesions:
early-stage primary, early, resectable neck disease (N1 or N2a); underwent surgery for the primary site.
When do you do add PORT?
positive margins, multiple positive nodes, or extracapsular extension
However, Lee et al.72 from the MD Anderson Cancer Center reported excellent
results with combined supraglottic laryngectomy and postoperative RT for
moderately advanced lesions.
Indications for PORT for supraglottic cancers.
-close or positive margins
-invasion of soft tissues of the
neck
-significant subglottic extension (1 cm or more)
-thyroid cartilage invasion,
-multiple positive nodes
-and extracapsular extension
General Management for Supraglottic Cancers:
RT Dose: Definitive RT
70/2/35 - high risk ctv
63/1.8/35 - intermediate risk ctv
56/1.65 - standard risk
General Management for Supraglottic Cancers:
RT Dose: PORT
Negative margins, 60 Gy/30fx
Microscopically positive margins, 66 Gy/33fx
Gross residual disease, 70 Gy/35fx
lower neck is treated with doses to 50 Gy/25fx
General Management for Supraglottic Cancers:
Why and how do you give stoma boost?
If there is subglottic extension;
the dose to the stoma is boosted with electrons, (usually 10 to 14 MeV) for an additional 10 Gy in five fractions.
What is the most common sequelae after RT for glottic or supraglottic lesions?
Laryngeal edema
