Head and Neck Cancer
Radiation Therapy 4412
Management of Head and Neck
Cancer
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Through multidisciplinary treatment we try
to:
1. decrease deformity
2. maintain the reduction of the tumor
3. restore function
4. preserve the structure and esthetics
5. cure the cancer
1. Compare and contrast the
epidemiologic factors prevalent in
head and neck cancers
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1/3 of patients that are treated have early
stage
2/3 of patients will have locally advanced
stages
Lungs are the most common site for mets
The nerve routes are important in
treatment planning, tumors can spread
this way
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Almost half of all squamous cell ca occur in the
oral cavity
Head and neck cancer involves the upper
aerodigestive tract.
 Oral cavity
 Pharynx
 Paranasal sinuses
 Larynx
 Thyroid gland
 Salivary glands
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Men- usually 50-60 years old
Can occur in people younger than 40 years of
age
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More women are smoking
Smokeless tobacco
Recurrences- usually within first 2 years
Rarely after 4 years
Most 5 year survivors will be alive at 10 years
2. List and describe the etiologic
factors associated with head and
neck cancers
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Smokeless tobacco- squamous cell of
cheek and gum
Previous radiation exposure- thyroid
/salivary glands
Poor oral hygiene
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Ill fitting dentures/irritation to tissues
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Wood mill workers- nasal cavity/paranasal
sinuses
Lip cancer- UV exposure, unfiltered cigarettes
Viruses
 Epstein Barr virus
 Herpes simplex (cold sores)
 HPV- oral/larynx
Chronic abuse of marijuana- degree of risk
unknown
Diet
 Vitamin A and E deficiency
 Plummer-Vinson syndrome- iron deficiency
anemia
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Alcohol
 Pharyngeal and laryngeal cancer
 Liver damage
 Secondary nutritional deficiencies
 Alcohol damages mucosa and makes
it more permeable
 Impurities in the alcoholic beverages
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Smoking
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Head and neck cancers occur 6x more
frequently than non-smokers
Unfiltered cigarettes
Cigar smoking is a risk
Laryngeal cancer mortality increases as the
number of cigarettes smoked increases
Smoking, tobacco, alcohol: a
deadly combination!
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Alcohol is synergistic to tobacco- cooperate
together to produce a total effect greater than
the sum of the individual elements
 Tars
 Aromatic hydrocarbons
 Ethanol suppresses the efficiency of DNA
repair
 Nitrosamines most noncombustible product
in snuff and chewing tobacco
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Pre-cancerous signs:
 Leukoplakia is a precancerous, slowly
developing change in the mucous
membrane. They are characterized by
thickened, white, firmly attached
patches that are slightly raised.
 Erythroplasia- A premalignant lesion
that is shiny, velvety and reddish in
color
 These are severe dysplastic changes
and should be taken seriously
Leukoplakia
3. Identify the prognostic indicators
in head and neck cancers
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Prognosis decreases as:
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The affected area progresses backward from
the lips to the hypopharynx (excludes larynx)
Lesions that cross the midline
Exhibits endophytic growth- invades within
the lamina propria and submucosa
Have cranial nerve involvement
Fixed nodes
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Fixed lesion in the anatomic
compartments
Are poorly differentiated
Nonsquamous cell
5. Compare and contrast
endophytic and exophytic tumor
features of head and neck cancers
*Endophytic growth- growth pattern that invades
the lamina propria and submucosa
-more aggressive and harder to control
locally
*Exophytic- a noninvasive neoplasm that projects
out from an epithelial surface
-characterized by raised, elevated borders
*Most head and neck cancers are infiltrative
lesions found in the epithelial lining
Staging
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Lymphatics of the head and neck are in
direct correlation to the prognosis
1/3 of the body’s lymphatics are in the
head and neck area
Staging depends on:
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Site of primary disease
Extent of primary disease
Size of primary tumor
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Staging cont’d
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Cell type and differentiation
Lymphatic vascular space invasion of the
tumor
The nodal status
6. List and describe the different
types of head and neck cancers
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Most head and neck cancers will infiltrate
into the epithelial lining of the upper
digestive tract
80% of all head and neck cancers will be
squamous cell
7. Compare and describe the
different types of head and neck
cancers.
8. Describe the different treatment
considerations for the different
types of head and neck cancers.
Oral Cavity
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Oral cavity extends from the skin vermilion
junction of the lip to the posterior border
of the hard palate superiorly
And the circumvallate papillae inferiorly
Anterior 2/3 of the tongue lips, buccal
mucosa, lower alveolar ridge, upper
alveolar ridge, retromolar trigone, floor of
the mouth, and hard palate
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Page 694 Washington/Leaver
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Oral cavity cancers
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The most common aerodigestive tract cancers
Occur mostly in men- 55 to 65 years old
Alcohol and tobacco are synergistic
Patients usually have poor oral and dental
hygiene
Plummer-Vinson syndrome is important
etiologic factor
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General practitioner or dentist will find the
cancer
Early diagnosis is important
Leukoplakia and erythroplasia are serious
Most oral cavity cancers will be nonhealing
ulcers with little pain
Localized pain is an advanced disease
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The cancer is usually raised, centrally
ulcerated, indurated edges and the base is
infiltrating
Mandatory biopsy
Squamous cell carcinoma makes up 90%95%
Well or moderately well differentiated
Has the lowest incidence (except glottic)
of nodal mets
Cervical node involvement=advanced
disease
Lips and Gum
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Lip cancer is treated with radiation the
same way as skin cancer
Usually involves the lower lip and spreads
by direct invasion
Carcinoma in-situ and early lesions of the
lip may be surgically removed
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Radiation Therapy:
 Portal should include primary lesion with
a 2 cm
 A shield (stent) of lead and bolus
material (to absorb backscatter) is
placed under the lip
 This blocks the alveolar process and
gums
 Treated with external beam, interstitial
implant or both
 100 SSD, 100% isodose line
Lip Cancer
Floor of Mouth
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Floor of the mouth lesions usually arise on the
anterior surface on either side of the midline.
They can spread to bone and tongue
Approx 30% of these cancers will involve the
submaxillary and subdigastric nodes
Opposed lateral fields are used
The tip of the tongue can be elevated out of the
portal with a cork or a bite block and tongue
depressor
Bite blocks can also spare the roof of
the mouth from incidental irradiation
 If the lesion has grown into the
tongue, the tongue is flattened to
reduce the superior border of the
portal
 Radiation therapy: supraclavicular
and bilateral neck fields, followed
with a boost of intraoral cone, needle
implants, or small external photon
beams
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Tongue
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The anterior 2/3 of the tongue is included
in the oral cavity
The base of the tongue is considered
oropharynx
Small tumors in the anterior 2/3 of the
oral tongue are usually resected
Radiation therapy is used for inoperable
patients
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Post-op radiation therapy
 Treats the primary site
 Treats the cervical lymph nodes
 And margins positive
 for tumor,
 extensive primary tumor with bone or skin
invasion,
 and multiple positive nodes
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The anterior tongue drains into the
 Submandibular lymph nodes
The posterior portion of the tongue drains into
the
 Jugulodigastric
 Posterior pharyngeal
 Upper cervical lymph nodes
Lesions of the tongue usually appear on the
lateral borders near the middle and posterior
third section
A limited number of tongue cancers can be
excised
Most are controlled with external beam and
interstitial boost fields
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Lesions at the base and posterior 1/3 of
the tongue invade
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The floor of the mouth
Tonsils
or the muscles
Are advanced
Have a higher incidence of nodal mets
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Hemiglossectomy- surgical removal of half the
tongue. It is used for treatment of an early
stage lesion of the tongue
Radiation therapy- three field technique
 Utilizes external beam, electron beam
 Possibly an iridium implant and neck
dissection
 Isocentric lateral opposed fields
 Lower anterior neck field
 Fields include subdigastric and submaxillary
nodes
 Upper cervical nodes
T1 Squamous cell of tongue
Buccal Mucosa
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Buccal mucosa is the mucous membrane lining
the inner surface of the cheeks and lips
Most lesions arise on the lateral walls
 Have a history of leukoplakia
 Are raised, exophytic growths
 Lesion invades the skin and bone
 First sign is a bump on the tip of the tongue
 No pain associated at first until the nerves to
the tongue or ear become involved
 Advanced lesions will bleed
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Stensen’s duct (parotid duct) can become
obstructed
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The parotid gland becomes enlarged
Small lesions are surgically removed
Large lesions are treated with surgery and
radiation therapy or
Radiation therapy alone
Complications- fibrosis of the cheek and
trismus
Hard Palate
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Located between the upper alveolar ridge and
mucous membrane covering the palatine process
of the maxillary palatine bones
Mostly adenocarcinomas and rare
Spread to the bone, invade the maxillary antrum
Treatment- surgical resection, post-op radiation
therapy
History of ill fitting dentures or trauma
Retromolar Trigone
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Triangular space behind the last molar tooth
Rare carcinomas
Symptoms- tongue, ear canal pain, trismus
Usually moderately differentiated squamous cell
carcinoma
Lymphatic spread to the submaxillary &
subdigastric nodes
Treated with radiation therapy
PHARYNX
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Subdivided into three anatomic divisions:
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Oropharynx
Nasopharynx
hypopharynx
Common symptoms
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Persistant sore throat
Painful swallowing
Referred otalgia
Cervical node enlargement
Fetor oris, dyspnea, dysphasia, hoarseness,
dysarthria, hypersalivation indicates advanced disease
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Diagnosis- indirect mirror exam, palpation,
biopsy, CT, MRI
Histopathology- squamous cell carcinomas
Staging- AJCC Classification
Mets- cervical lymph nodes (bilateral),
retropharyngeal nodes, lung
Oropharynx
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Consists of the base of the tongue, the
tonsils (fossa and pillars), soft palate,
oropharyngeal walls
The oropharynx is located between the
axis and C3 vertebral bodies
Soft tissue regions- anterior tonsillary
pillars, soft palate, uvula, base of the
tongue and the lateral-posterior
pharyngeal walls
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Tonsils are the most common site for
disease
Symptoms- sore throat and pain during
swallowing
Upper spinal accessory nodes are involved
bilaterally in 50% to 70% of the patients
Radiation therapy is treatment of choice
Cancer of tongue
Hypopharynx
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Pyriform sinuses, postcricoid, and lower
posterior pharyngeal walls below the base
of the tongue
It is situated between C3 to C6
The cricoid cartilage is the inferior border
Epiglottis is the superior border
Hypopharyngeal cancer is advanced
High rate of nodal mets
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Tumor is highly infiltrative
The highest area for incidence is the
pyriform sinus
Radical surgery and radiation therapy is
the treatment of choice
Rouviere’s (lateral retropharyngeal) lymph
nodes at the base of the skull are included
with other nodal groups in treatment
(page 706, Washington)
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Tonsillar, pharyngeal wall and posterior
cricoid are treated using radiation therapy
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(page 709, figure 30-28, Washington)
Unresectible T4 pyriform sinus
tumor, surrounding carotid artery
Nasopharynx
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Posterosuperior pharyngeal wall and lateral
pharyngeal wall, the eustachian tube orifice and
adenoids
The nasopharynx is a cuboidal structure lying on
a line from the zygomatic arch to the external
auditory meatus (EAM), extending inferiorly to
the mastoid tip
The nasopharynx lies behind the nasal cavities
and above the level of the soft palate
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The nasal cavity drains into the
nsopharynx via the two posterior nares
Two eustachian tubes are on the lateral
walls which connect to the middle ear
Nasopharyngeal disease can mimic an
inflammatory process
Can cause considerable respiratory or
auditory dysfunction
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The cranial nerve is frequently involved
The ninth to the twelfth cranial nerves can
be affected
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Enlargement of the retropharyngeal nodes
Can affect the external carotid artery
A lesion can invade directly into the third
cranial nerve
Commonly involves the sixth cranial nerve
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When cranial nerves are involved, this
means the disease is advanced and
widespread
Histology- squamous cell
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Nasopharyngeal cancer is usually poorly
differentiated and shows an unusual growth
pattern
This disease is not associated with tobacco
consumption
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NPC is associated with the Epstein Barr
virus
Can occur in adolescence and young
adults
Occurs again between 50 and 70 years of
age
Uncommon in white populations
Found mostly in southern China and the
Middle East
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Positive cervical nodes in 75% to 85% of
NPC patients
About half of all cases will have bilateral or
contralateral disease
Radiation ports are large
The lateral retropharyngeal (node of
Rouviere) which cannot be surgically
removed, and jugulodigastric nodes are
almost always treated
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Primary lesion is small but the nodal
disease is extensive
Bone and lung common mets sites
NPC spreads to adjacent sites and has a
high recurrence rate
Aggressive, large volume curative
radiation therapy is given
Larynx
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The larynx is contiguous with the lower
portion of the pharynx above and is
connected with the trachea below.
It extends from the tip of the epiglottis at
the level of the lower border of the C3
vertebra to the lower border of the cricoid
cartilage at the level of C6
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There are 3 main parts to the larynx. These
parts are:
The supraglottis - the area above the vocal cords
that contains the epiglottis cartilage
The glottis - the area around the vocal cords
The subglottis - the part below the vocal
cords, containing the cricoid cartilage. It
continues down into the windpipe
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Glottic cancer- 65%
Supraglottic cancer- 25% to 33%
Subglottic- make up the rest of the cases
Most common cancer in the aerodigestive
tract is the larynx
Male dominated disease
50-60 years of age
Smoking high risk factor
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Extensive use of voice in occupation is risk
factor (singers, auctioneer) for laryngeal
cancer
Alcohol high risk factor for supraglottic
cancer
Cancer of the glottis (true vocal cord) is
not life threatening
Choice of treatment is based on the
preservation of speech and airway
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Laryngeal cancer shows a mutation of the
p53 gene
Classic Symptoms- persistent sore throat
and hoarseness
Cervical lymph nodes involvement is
associated with supraglottic lesions
Carcinoma in situ is common on the vocal
cords
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Glottic lesions are well to moderately
differentiated
Supraglottic lesions are less differentiated
and more aggressive
Glottic lesions will appear of the anterior
2/3 of one cord (approx 65%-75%)
Cord mobility is a factor in the
classification of lesions
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Treatment- radiation therapy is the treatment of
choice for nonfixed surface glottic lesions that
have not invaded muscle, bone or cartilage
Glottic cancer is treated with lateral opposing
fields 5X5cm or 6X6 cm
Large, fixed lesions will require aggressive
treatment
Radiation therapy offers the best voice
preservation
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Supraglottic lesions are usually large and
bulky
They do not usually invade the inferior
false cord or the ventricles
These lesions usually spread superiorly to
the epiglottis
Lymph nodes are usually involved in 40%50% of the patients
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Subglottic lesions are treated with total
laryngectomy with
Post-op radiation therapy
Larynx- squamous cell, Rt anterior
vocal fold
Salivary Glands
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Salivary glands are made up of:
 Parotid-largest gland, located superficial to
and partly behind the ramus of the mandible,
and covers the masseter muscle
 It fills the space between the ramus of the
mandible and the anterior border of the
sternocleidomastoid muscle
 Contains extensive lymphatic capillary
plexus many aggregates of lymphocytic
cells
 Numerous intraglandular lymph nodes in
the superficial lobe
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Submandibular glands
Sublingual glands
Tumors of the salivary gland are rare
The parotid is the most common site for tumors
Nearly 2/3 of these tumors will be benign
Low-dose ionizing radiation in childhood may
have been a risk factor
Dental x-rays have been implicated for both
benign and malignant tumors
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Most major and minor salivary gland cancers are
of unknown origin
Adenoid cystic, mucoepidermoid, and
adenocarcinoma are the most common cell
types
Symptoms- asymptomatic parotid mass lasting
4-8 months before the tumor arises
Presenting symptoms- localized swelling and
pain, facial palsy, & rapid growth
Facial nerve involvement suggests malignancy
Diagnosis is done through lobectomy
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Treatment- Although most tumors are benign,
local recurrence is high
Total resection with margins sparing facial
nerves
Radiation therapy- post-op for residual, recurrent
or inoperable tumors
Accelerated fractionation- provides similar dose
levels of radiation therapy in a shorter amount
of overall time. This counteracts quick cellular
proliferation of aggressive tumors by giving
more dose in a shorter period of time.
Maxillary Sinus
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Maxillary sinus is a pyramid shaped cavity
lined by ciliated epithelium and bound by
thin bone or membranous partitions.
Carcinomas arising from the ciliated
epithelium or mucous glands perforate the
bony walls almost from the beginning
Tumors will also involve the superior
portion of the sinus and extend into the
floor of the orbit
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Maxillary sinus cancers- 80% of all sinus
cancers
Long history of sinusitis, nasal
obstructions and bloody discharge
Squamous cell carcinomas
Invade the floor of the orbit, ethmoid
sinuses, hard palate & zygomatic arch
Displacement of the eye is common
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Nasal cavity and paranasal sinus tumors
are often associated with cranial nerve
palsies- trigeminal branches
CT and MRI are the most useful studies
Submandibular node will be the first
involved, although cervical node spread is
uncommon
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Treatment- Surgery is the treatment of choice
Primary radiation therapy has a chance of optic
nerve damage from the high dose required for
tumor control
Surgery and radiation therapy used in most
cases
Lateral and anterior ports are used
When the orbit is involved, eye blocking will not
be used
Care should be taken to miss the cord and
contralateral lens
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Angling the anterior beam a few degrees
off the vertical spares brain tissue
Nasal cavity risk- Bolus material will be
inserted to improve dose homogeneity
Angling the lateral port a few degrees off
the horizontal plane spares the
contralateral optic nerve and lens
Management of the Head and
Neck Patient
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Washington, Page 718, Table 30-3, dosetissue response schedule
Page 719, Box 30-11, recommended skin
care program
Care of the head and neck patient
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Peridontal disease and caries
Nutrition
Mucositis/stomatitis
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Xerostomia
Cataract formation
Lacrimal glands
Taste changes
Skin reactions