Carcinoma Nasopharynx

Carcinoma Nasopharynx Moderator: Dr Sushmita Ghoshal

Anatomy

Anatomy Foramen lacerum Foramen spinosum Foramen ovale Foramen rotundum

Parapharyngeal Space
The parapharyngeal space is located deep within the neck lateral to the pharynx and medial to the ramus of the mandible.
Shape of an inverted pyramid with the floor at the skull base and it’s tip at the greater cornu of the hyoid bone
Two compartments :
Prestyloid
Retrostyloid
Retrostyloid Space Prestyloid Space

Lymphatic Drainage
Richest lymphatic plexus in the head and neck region.
Submucosal lymphatics congregate at the pretubal region – “pretubal plexus”.
These then pass on to the retropharyngeal nodes as 8 -12 trunks which decussate in the midline.
Lymphatic trunks pierce the level of the base of the skull and run between the pharyngobasilar fascia and the longus capitis.
The lymphatic trunks drain in three directions:
To the retropharyngeal nodes.
To do the posterior cervical nodal and the confluence of the 11 th , cranial nerve and the jugular lymph node chains, situated at the tip of the mastoid.
To the Jugulo-digastric nodes (Lederman )

Anatomy: RPLN
The retropharyngeal nodes are present in two groups.
Median group.
Lateral group.
The median group consists of 1 - 2 nodes interconnected in the midline.
The lateral group consists of 1- 3 nodes located between the lateral aspect of the posterior pharyngeal wall and the carotid artery.
These nodes are present from the vertebral levels C1- C3.
The superior-most lymph node of the latter group is also known as the node of Rouviere.
This node lies in front of the arch of the Atlas being separated from it by the longus colli muscle.

CT anatomy

Incidence

Incidence: Sex

Clinical Features
Most common: Asymptomatic cervical lymphadenopathy (87%)
MC node involved is the posterior deep cervical (direct drainage from the lateral pharyngeal)
Other presenting symptoms:
Nasal twang to speech
Unilateral serous otitis media ( in adults)
Cranial nerve palsy :
U/L Cr nv. II to VI (petrosphenoidal syndrome of Jacod)
U/L Cr nv. XI to XII ( Retroparotid syndrome of Villaret.)
Cr nv V and VI most commonly involved.
Cr nv I, VII and VIII rarely involved.
Sore throat : Oropharyngeal extension
Pain : Compression of Vth cranial nerve ( facial pain)
Trismus : Mandibular nerve involvement or pterygoid muscle invasion.

Cranial Nerve involvement

Local Spread Nasal cavity & PNS Orbital invasion Base of Skull, Clivus Sphenoid sinus Cavernous Sinus Lateral Parapharyngeal space Middle ear cavity Oropharynx (tonsillar pillars) C1 vertebrae

Nodal Spread

Etiology Normal Epithelium Low Grade Dysplasia High Grade Dysplasia Invasive Carcinoma Metastatic Carcinoma P53 Mutation Gain Chromosome 12 Deletion 11 and 13 Deletion of Chromosomes 3p and 9p Inactivation of Chromosome p14, 15 and 16 EBV infection

Investigations
Staging:
CT
MRI
Endoscopy
PET scan
Chest Xray
USG Abdomen
Bone Scans
Other Investigations
EBV Serology

Staging
Several staging systems are in use:
Complex anatomy and spread patterns
Lack of international consensus:
Separate Chinese, Hong Kong and American staging systems
Systems available:
Fletcher (1967)
Ho’s staging (1978)
IUAC (1988)
Huaqing staging (1994)
AJCC (2002)

Comparison Infratemporal fossa / cavernous sinus / PNS / direct invasion of C2 or C1 / anterior cranial nerves Pterygoid process / posterior cranial nerve / posterior cervical vertebrae / BOS / PPS beyond SO line Involving the nasal cavity, oropharynx, anterior cervical vertebrae, PPS before SO line Limited to nasopharynx Huaqing (1994) Bony destruction including eustachian tube No bony destruction Extending to two sites in nasopharynx Limited to one site in nasopharynx IUAC (1988) NA Bone/ Cranial nerve/ orbital / hypopharyngeal / infratemporal fossa involvement Extending to nasal fossa or oropharynx Confined to nasopharynx Ho (1978) Involving skull base or cranial nerves Beyond nasopharynx > 1 cm but confined to nasopharynx < 1 cm diameter Fletcher (1967) T4 T3 T2 T1 Staging System

Ho’s vs AJCC

AJCC system: T staging
T1 :
Tumor confined to the nasopharynx
T2 :
Tumor extends to soft tissues
T2a : Extends to the oropharynx or the nasal fossa
T2b : With parapharyngeal extension
T3 :
Tumor invades bony structures and/or paranasal sinuses
T4 :
Tumor with intracranial extension and/or involvement of cranial nerves, infratemporal fossa, hypopharynx, orbit, or masticator space

AJCC system: N staging
N0 :
No regional lymph node metastasis
N1 :
Unilateral metastasis in lymph node(s), < 6 cm in greatest dimension, above the supraclavicular fossa
N2 :
Bilateral metastasis in lymph node(s), < 6 cm in greatest dimension, above the supraclavicular fossa
N3 :
N3a: Metastasis in a lymph node(s) >6 cm
N3b: Extension to the supraclavicular fossa
Ho’s Triangle

Staging: AJCC 2002 Stage I Stage IIA Stage IIB Stage III Stage IVA Stage IVB

Pathology
Some authors consider carcinomas to be of two types:
Keratinizing
Non keratinizing
Others consider carcinomas to be of 4 types:
Keratinizing Squamous
Non Keratinizing Squamous
Lymphoepithelioma
Undifferentiated carcinomas
WHO 3 types:
Type I : SCC
Type II : Non Keratinizing carcinoma
Type III : Undifferentiated carcinoma

Endemic NPC
Known to occur in China, Hong Kong, South Eastern Asia, Greenland
Associated with EBV virus infection
In India similar pathology seen in Kashmiris.
Present a decade younger.
Not associated with smoking or alcohol consumption
Associated with undifferentiated carcinoma ( WHO II and III)
Associated with more advanced disease at presentation
Nodal stage also more advanced and more frequently involved.
Both chemo and radio sensitive
Histologically more vascularized (Better Rx response)
Greater % of cell in the growth fraction.
Better loco regional control and survival than sporadic variants.
Several markers for predicting biological behavior

Prognostic factors
Most important stage.
Parapharyngeal extension is associated with a poorer prognosis.
A Chinese series found that 4 th cranial nerve involvement – poor prognosis.
Nodal disease status:
Bilateral cervical lymphadenopathy
Supraclavicular lymphadenopathy
Lymph node fixity
Lymphoepithelioma histology: better prognosis
Undifferentiated histology: better prognosis
Molecular markers:
Ki -67 over expression
P 53
E – cadherin expression

Treatment strategy Stage Early stage Late stage External Radiation EBRT + ICBT KPS > 70 KPS < 70 Concurrent Chemoradiation Palliative Radiotherapy

Dose response
Significant dose response relationship exists.
Several series demonstrate that an increased-dose leads to better survival
Doses of 90 Gy delivered by boost increase the local control and the distant metastasis free rate significantly over doses > 70 Gy
Price however paid in increased morbidity
Local recurrence rate reduced with the use of larger fields (Field size more than 250 cm 2 associated with a doubling of local control as compared to field size of 100 cm 2 )

Dose-response

Doses used
Radical radiotherapy:
60 – 66 Gy in 2 Gy per fraction over 6 – 6 ½ weeks
Higher dose can be given with more conformal techniques:
ICBT
IMRT
3 DCRT
In our patients with poor nutrition, advanced disease and absence of individualized care split course radiotherapy is an alternative
35 Gy in 15 #
25 – 30 Gy in 10 – 15 # after 2-3 weeks
Palliative radiotherapy:
30 Gy / 10#
20 Gy / 5#
800 -1000 cGy single fraction

Treatment volume
The nasopharynx.
Posterior 2 cm of nasal cavity.
Posterior ethmoid sinuses.
Entire sphenoid sinus and the basiocciput
Cavernous sinus.
Base of skull, including the foramen ovale, carotid canal and foramen spinosum.
Pterygoid fossae
Posterior 1/3 rd of maxillary sinus.
Lateral and posterior oropharyngeal wall to the level of mid-tonsillar fossa
Posterior 1/4 th of orbit ( Fletcher – YES, Perez - NO )

Nodal volumes
The entire neck is at high risk for microscopic spread of disease.
The neck nodes that should be treated are:
Upper deep jugular
Submandibular
Jugulodigastric
Midjugular
Posterior cervical
Retropharyngeal

Treatment planning
Positioning:
Supine position.
Head should be extended
Immobilization
To ensure accuracy in setup patient should be immobilized with a custom-made thermoplastic cast.
Localization:
All nodes are delineated with the use of radio – opaque lead wires.
The outer canthus the eye opposite to which simulation film is taken is marked with a lead wire.
Tumor localization performed with the help of CT and clinical details.

Techniques
Techniques
Conventional technique
Three-dimensional conformal radiation therapy.
Intensity-modulated radiotherapy.
Image-guided radiotherapy.
Energy selection:
Co 60 : 1.25 MeV
LINAC : 4 – 6 MV
Higher-energies used in certain Western centers during the boost phase to:
Reduce dose to the mandible, temporomandibular joints, ears and subcutaneous tissue (lateral edge effect)
Kutcher and associates however warn that use of these high energy beams may be associated with underdosage near the surface and near the paranasal sinus cavities.

Portal selection
For Initial Phase:
Two parallel opposing fields
Three field approach
For the boost phase:
Fletcher’s Technique ( 4 fields – antral boost)
Anterolateral wedge pair technique
Ho’s technique ( with separate parapharyngeal boost)

Two field technique
Clinical field markings:
Superior border:
2.5 cm above the zygomatic arch
5 cm above the zygomatic arch in case of intracranial extension
Anterior border:
2 cm beyond the anterior most extent of the disease (usually placed just along the lateral canthus of the eye)
Posterior border:
Along the tip of the mastoid or behind the posterior most extent of cervical lymphadenopathy
Inferior border:
Along the superior border of the clavicle

Two Field technique
Radiological boundaries:
Superior border:
Splitting the pituitary fossa and extending along the superior surface of the sphenoid sinus
In case of IC extension to include at least 1 cm above the pituitary fossa.
Anterior border:
At least 2 cm of the nasal cavity and maxillary antrum.
At least 2 cm margin to the gross tumor extent
Posterior border:
Kept open if gross cervical LAD
Else match with tips of spinous processes of the cervical vertebrae.

Technique

Three field technique
The superior, anterior and posterior boundaries are kept as same.
Inferior boundary restricted to the level of the thyroid notch unless cervical LAD is present
In latter case matching done more inferiorly.
Dose prescription done usually at 3 cm depth.
Several measures need to be taken to circumvent the problem of field matching

Field Matching
Without asymmetrical jaws :
Using laryngeal block :
A laryngeal block is placed at the level of the larynx.
The block has a thickness such that it is located 1cm medial to the lateral border of thyroid cartilage
The block extends from the superior border of the lower field to 2 cm below the level of the cricoid cartilages.
Using collimator tilt :
A collimator rotation may be given for the lateral fields to counteract the divergence of the lower anterior field – 5 ° for Co 60.
May increase the dose to the supero-anterior portion of the field where the eyes are located
With asymmetrical jaws :
Using an isocentric technique with half beam block for 3 fields overdosage at the field junction can be avoided.
Alternative is to use half beam block in the lower anterior field only and use a small shield of 1 – 2 cm in midline to shield the spinal cord.

Additional modifications
In both 3 field and 2 field techniques a higher dose can be given to the eye due to the beam divergence.
Lateral fields need to angled – a “posterior” tilt needs to be given
Magnitude by which the field edge shifts at the midline ( for Co 60 )
5 ° – 0.5 cm
10 ° – 1.2 cm
5° 10° 1.2 0.5 1.1 2.5

Actual Implementation 270 ° 5 ° 275 ° Lateral Canthus

Doses Prescribed
40 – 44 Gy in 2 Gy per fraction over 20 – 22 fractions ( 4 – 4½ weeks) for the entire field.
Rest of the dose ( 20 – 26 Gy) to delivered with spine shielding:
Lateral fields :
Posterior border drawn along the junction of the posterior 1/3 rd and the anterior 2/3 rd of the vertebral bodies ( Co 60 ).
In LINACs the posterior edge of the vertebrae may be choosen.
Clinically marked straight along the lobule of ear.
Anterior fields :
2 cm wide midline shield is adequate.

Boosting neck nodes
Photons only :
Antero-posterior glancing fields ( ± wedges) – Medial border is 2 cm from midline.
Additional boost radiation may be delivered by posterior fields to increase the dose to the posterior cervical nodes after the course of RT is completed.
Electrons :
Direct abutting lateral fields used.
Energy selected 9 MeV
Prescribed at 85% isodose ( Usually 3 cm depth)
6 x 6 cm usually adequate
Treated at extended SSD of 110 cm

Nasopharynx Boost
A 4 field approach can be used to boost the nasopharynx to additional 10 – 15 Gy.
Volume treated is roughly cuboidal and has the dimensions of 7 cm x 6 cm.
The anterior fields are tilted “medially” by 20 ° – 30 ° in order to
Increase the dose to the Posterior nasopharynx
Spare the anterior nasal cavity and the deeper brain-stem
Opposing lateral fields also used with lower border at the level of angle of mandible.

Field marking
The boundaries for the anterior facial fields are:
Superiorly – below the eyeball
Medially – 1 cm in either side of midline
Inferiorly – upto the commissure of lips
Laterally – Usually a distance of 6 cm – allow beam fall-off.
In order to ensure that the superior border of the anterior field matches the lateral fields the head position is adjusted (hyperextended) based upon the collimator lights.
Beam weights are adjusted to ensure that the brain doesn't receive excess dose.
Anterior : Lateral = 33% : 66%

4 field technique

Dose distribution

Nasopharynx Boost
In case of gross anterior extension :
Three field, lateral wedge pair arrangement is preferred
Anterior border of the lateral fields are extended to cover the anterior disease adequately
Alternative technique is to use differential beam weights
Electrons may be used to supplement the doses to the anterior diseases with lateral photon fields.
In lateralized anterior extension :
Anterior field may be “wedged” with thin end towards side where disease is present.
In inferior extension :
Boost fields are by necessity parallel opposing.

Ho’s Technique
Proponent: Prof John H C Ho
Developed: late 1960s
Extensive experience : 3 decades
Special features:
Different CTV specification
Field arrangements and patient position are different.
Arrangement of different shields specified based upon bony anatomy – customized shields not necessary.
Reproducible treatment plan.
Lack of CT planning facilities circumvented.
Ease of use in a busy radiotherapy department Cost saving additional factor.
Over 10,000 patients have been treated in Hong Kong – excellent long term results in early disease T1, T2 and T3.

Ho’s technique: Planning
Patient is immobilized in FLEXED head position in the initial phase.
Similar to the planning technique for pituitary.
Allows easier shielding of the brainstem and the oral cavity and reduces the field size requirements.
Dose: 40 Gy in 20 #

Three field arrangement:
Opposed lateral fields irradiate the upper cervical lymphatics ( upto level III) en bloc.
An anterior field irradiates the lower field.
Shielding of the lateral fields is done to adjust for the beam overlap with the anterior field.
In the lower anterior field a midline shield is placed throughout the treatment.
Below vocal cords C6 0.5 cm above the anterior clinoid process Bisecting the maxillary antrum

Specialized arrangement of shielding is done for all patients.
Brain Stem : Shielded with 5 HVL block placed in a manner such that it is 0.5 cm behind the upper edge of the clivus and 1 cm below the lower edge.
Eye : 5 HVL shield placed 1.5 cm behind the lateral canthus.
Posterior tongue also shielded with standard block.
Pituitary and temporal lobes : upper half of the pituitary fossa shielded.

In the boost phase a 3 field arrangement was used.
Patient was replanned in the EXTENDED head position with oral stent.
Anterior cervico-facial field was used in all patients
Lower border of the later fields reduced down to level of angle of mandible.
Allowed dose reduction to: TM joints, ear, parotids & pinnae.
Dose prescribed: 22.5 Gy in 9 #
Total tumor dose was 62.5 Gy in 29#
Biologically equivalent to 66 Gy in 33#

In patients with parapharyngeal disease a posterior oblique boost was given after the 2 nd phase.
Dose prescribed was 20 Gy /10#
This field was usually 5.5 cm x 8 cm in size.
Ascending ramus of the mandible was shielded in this phase.

Ho’s vs 3D CRT and IMRT T1 NO MO T4 N2 MO Kam et al: IJROBP 2003

Results by Ho’s Technique

Conventional Radiation

Altered fractionation
Concomitant boost technique has been evaluated in a large series by Teo et al (IJROBP 2000).
Study prematurely terminated as:
40% incidence of temporal lobe neuropathy
17% incidence of cranial nerve palsies
50% patients had one or other form of neurological complication
2.6% treatment related mortality
Neural complications were more severe and occurred earlier than conventional techniques.
No difference in outcome

Conformal Radiation
Includes 3 D CRT , IMRT and IGRT
Potential:
Dose escalation
Conformal avoidance
Results are immature for IMRT
Largest series of IMRT by Kam et al:
63 patients
Median F/U 30 months
Only 4 had local failure ( None marginal miss)
OS was 90%
Distant metastasis primary cause of failure
Grade III mucositis: 41% patients
Late toxicity till 2 yrs : Xerostomia (21%)

Brachytherapy
The following requirements should be fulfilled prior to taking up a patient for brachytherapy:
Tumor thickness less than 10 mm.
Absence of intracranial, paranasal sinus and oropharyngeal involvement.
Absence of involvement of underlying bone or infratemporal fossa.
Absence of metastatic disease.
Expertise in nasopharyngeal intracavitary brachytherapy.
“ In effect, nasopharyngeal brachytherapy is ineffective in tumors extending beyond the nasopharynx” -Xiao-Kang Zheng

Techniques
Techniques:
Temporary intracavitary application
Temporary interstitial implantation
Permanent interstitial implantation
Dose-rates used:
Low dose rate (LDR).
High dose rate (HDR).
Situations used:
Routine use as a boost after XRT ( Hong Kong, China and Netherlands)
Use with documented residual disease ( USA)
Recurrence ( Hong Kong, USA - Syed and Chinese Series)

History of brachytherapy
In 1920s, Pierquin and Richard were the first persons is to employ brachytherapy in the treatment of nasopharyngeal carcinomas.
In the Christie hospital at Manchester, Peterson used a 15 mg radium tube inserted in a cork with a diameter of 15 to 20 mm.
The dose prescribed was 80 rads in seven days to a depth of 0.5 cm.
Peterson described this technique as a useful alternative to small field X-ray technique but not superior to the use of X-rays
Cork Ra 226 tube String at either end of the cork

Applicator Design
Several applicator designs available:
Mould technique
Levendag’s
Forzhou (Chinese district)
Simple catheter based

Mould Technique
Customized mould prepared for each patient
Uses a special quick setting silicone jel to take the nasopharyngeal impression.
The source placement for an average nasopharynx are:
2 sources for 1 wall
3 sources for two adjoining wall
4 sources for 3 walls
Intersource separation kept at 1 – 1.5 cm.

Technique of Insertion

Rotterdam Applicator
Designed by Levendag.
Designed so that the applicator could be worn by the patient comfortably continuously throughout the fractionated course of treatment given.
Made up of silicone which is flexible and closely conforms to the curvature of the nasopharynx.
Applicator design based upon a 3 D model of the nasopharynx ( based on CT of two patients)
Allows closer fit to the base of the skull and situated at a fixed distance from the soft palate.
A silicone bridge and flange used to fix the applicator against the posterior nasal septum and the anterior one respectively.

Rotterdam Applicator
Tube diameter
Outer diameter 15 F (5.5 mm)
Inner diameter 9 F ( 3.5 mm)
Can accommodate the 6 F HDR source easily.
Two tubes ensure catheter stability.
The tubes are diverging at the base

Prescription and points
Several anatomical points defined by Levendag to calculated dose to the tumor as well as critical normal tissues.
Tumor points :
Na (Nasopharynx) – 2
BOS (Base of Skull) - 2
R (Node of Rouviere) - 1
Normal Tissue points :
OC ( Optic Chiasm) - 1
P (Pituitary gland) - 1
C (Cord) – 1
Pa (Soft Palate) – 2
Re (Retina) - 2
No ( Nose) - 2

Prescription points BOS Pa R Na Re P OC C Pa Pa C R OC Re Re BOS BOS Na Na P No No No Line 1 Line 2

Dose prescribed
In case EBRT given in dose of 60 Gy:
3 Gy x 2 fractions per day for 6 fractions by HDR
Total dose ~ 78 Gy
Minimum interfraction gap of 6 hrs.
In case of EBRT given in dose of 70 Gy:
3 Gy x 2 fractions for 4 fractions by HDR
Total dose ~ 82 Gy
Minimum interfraction gap of 6 hrs.

Advantages
Comfortable applicator – can be kept between fractions
Optimization possible – Na, BOS and the R points.
Can be reused after steam sterilization.
Reduced normal tissue dose – to the retina, palate and the nasal cavity
In earlier work Levendag used to use two other points:
FL point :
corresponding to the BOS point
Approximates the position of the foramen lacerum
FO point:
Situated at the foramen ovale
Taken 2 cm lateral to the midline in then same plane as the BOS point.

Disadvantages
Nasal synechia have been observed in few patients.
Corresponds to the hyperdose sleeve of 200% isodose around the applicator.
Approximately occurs in a radius of 6 mm around the source axis after standard prescription
Reduced by use of nasal pack for 7 days after ICBT
Optimization can result in increased dose to some points (especially the spinal point).

Chemoradiation
Sequence:
Induction
Concurrent
Adjuvant
Concurrent regimen is best.
Principle:
Local cooperation
Spatial cooperation
We use Concurrent Cisplatin in doses of 50 mg/m 2 D 1 and D 22 .

Results: NACT

Results: Adjuvant CT
Adjuvant Chemotherapy:
Of no benefit even if CDDP based.
Chi et al reported results of a phase III randomized trial (2002) N = 157
Adjuvant chemotherapy with 24 hr infusional Cisplatin 20 mg/m 2 , 5-fluorouracil 2,200 mg/m 2 , and leucovorin 120 mg/m 2 x 9 cycles after 70 Gy XRT
5-year overall survival 60.5% vs. 54.5% (p = 0.5)
5 yr relapse-free survival rates 49.5% vs. 54.4% (p = 0.38)

Results: Concurrent CT
Huncharek et al performed a meta-analysis in 2002.
6 RCTs included
Statistically significant increase in the disease free survival by approximately 20% to 40%
OS improved by ~ 20% (Statistically NS)
Better results with Cisplatin + 5 FU based regimen ( Al Sarraf)

Results : Metastatic disease

NPC in Children
Problem of long term toxicity:
Skull deformities
Neurological deficits
Pituitary dysfunction
Hearing impairment
TM joint ankylosis
Visual defects
RT is the treatment modality of choice:
Dose 50 -60 Gy
Boost only after skull growth is complete (15yrs)
Lower neck usually not treated if clinically –ve.
Outcome:
DFS is 70 – 80% in T1 and T2 tumors
DFS is 40 – 50% in T3 – T 4 tumors

Recurrence
2 types described (Wang et al)
Persistent disease
Relapse: Appearing 1 yr after treatment.
Detecting recurrence:
Tc 99m SPECT
MRI – High signal intensity on T1 weighted spin echo images
Options:
Palliative treatment
Radiation therapy
Surgery

Surgery
Usually indicated in situations like isolated nodal recurrence
Local recurrences have been salvaged by extensive craniofacial surgery

Radiotherapy
EBRT
Brachytherapy
Both temporary and permanent implants used.
Best results from Gold grain implantation.
IMRT and 3 DCRT
Investigational
Sterotactic Radiosurgery
Chemotherapy
Cisplatin or taxane based
Mainstay in:
Distant spread
Early recurrence
Extensive disease

Radiotherapy
External radiotherapy:
High energy beams are better choosen
Small 6 x 6 field used to treat site of local recurrence
Doses in range of 20 – 30 Gy.
Indications:
Limited tumour size,
a relatively long period since previous irradiation (minimal time period ~ 1 year)
Good performance status and
Lack of evidence of skin or soft tissue damage (skin fibrosis, atrophy or telangiectasis) from the previous irradiation course

Results of RT

Results

Neurological Sequelae
Hypothalamo-Pituitary dysfunction
Median incidence of clinical dysfunction is 3%.
Cumulative incidence of endocrine dysfunction higher at 67% at 2 yrs .
Most common disturbance seen in GH secretion .
Thyroid hormone production affected the least.
Hearing defects :
Almost 7% patients become deaf with standard therapy.
Otitis media seen in 14% patients
Prolonged tinnitus may be seen in 30% patients
Temporal lobe injury :
Incidence as high as 3% after 2 yrs.
Toxicity more in altered fractionation regimens
Cranial nerve injury :
The incidence is as high as 6%.

Other Sequelae
Significant xerostomia can be seen in as high as 80 %
Some degree of xerostomia is seen all patients.
Fibrosis of the subcutaneous tissue is seen when doses exceeding 50 Gy are used in almost 16% patients.
Significant trismus, can occur in 5 to 10% patients.
This particular complication can be reduced by using a three-field approach for boosting the nasopharynx.

Conclusions
Nasopharyngeal malignancies make up a different population of head and neck malignancies.
These are eminently radio sensitive and curable.
Treatment planning is by necessity complicated and time consuming.
Brachytherapy can be used for boosting the local activities.
Chemoradiation is standard treatment in locally advanced tumors

Thank You

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Carcinoma Nasopharynx

by fondas vak on Feb 07, 2010

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Carcinoma Nasopharynx — Presentation Transcript