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HYPOPHARYNX
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Treatment of Early
Hypopharynx Cancer
Radiation
Aim for single modality
treatment to cure with minimal
toxicity while preserving both
organ and function
IMRT
1.8-2 Gray per fraction, 5 days
a week for 6 weeks
is typical dosing
Overall results are favourable
however there is a risk of
second malignancies - either
synchronous or metrachonous
cancers develop in treated
patients which maybe decades
down the line.
Partial
pharyngectomy
TypesReconstruction options
pharyngolaryngectomy
Principles of surgery:
(1) Aim to treat with
single modality
(2) Choice dependant on:
voice/swallow/respiratory
function/age/occupation
(3) Based on T1/T2
Larynx conservation surgery
(1) Externa
Suitable for:
- Small tumours <4 cm
- PC or pyriform apex clear
- No erosion of cartilage
- Mobile vocal cords
Partial
Laryngopharyngectomy
Partial
Pedicled Free ap
Pectoralis
major
- Small tumours <4 cm
- PC or pyriform apex clear
- No erosion of cartilage
- Mobile vocal cords
- Good exposure/access
TOLM TORS TOVS
e.g. Radial forearm or
anterolateral thigh ap
2) Transoral
Suitable for:
Figure 63.2 Treatment options for early hypopharyngeal cancer (TOLM = transoral laser micro-
surgery, TORS = transoral robotic surgery, TOVS = transoral video-assisted endoscopic surgery).
Chemoradiotherapy for Advanced Hypopharyngeal Cancer
Concomitant chemoradiation in hypopharyngeal cancers was found to be better than induction chemotherapy. Single-agent cisplatin is the standard of care, but there is a decreasing
eect of chemotherapy in patients over 70 years old. Chemoradiation is generally accepted
as the gold standard of treatment in advanced laryngeal cancers without frank cartilage
erosion.
Salvage Surgery After Organ Preservation
e premise for oering organ preservation is the ability to salvage if the treatment does
not succeed. Communicating this is critical in counselling the patient whilst planning
treatment.
Residual Local Disease
e hypopharynx is at the highest risk for locoregional and distant spread. Control rates
aer primary radiotherapy/chemoradiation are low, with around 30–50% of patients having
residual/local recurrences. Most of these patients tend to have unresectable lesions. When
the case is salvageable, most oen the surgery is laryngopharyngectomy with pharyngeal
reconstruction, but the outcomes are bleak, with a successful salvage rate of only 17.1%.
Salvage laryngopharyngectomies have an increased rate of complications, especially pharyngocutaneous stulae, which may occur in up to 50%. Pharyngocutaneous stulae in turn
increase the incidence of carotid artery blowouts. Mortality in surgically treated hypopharyngeal cancers is a reality, with average hospital mortality rate for laryngopharyngectomy
around 6%, with the gastric pull-up group having the highest incidence, 11%. Because of the
low salvage potential and the high rate of complications, it is imperative to carefully choose
patients for organ preservation, and the surgical team should have a low threshold for using
vascularised tissue from non-radiated areas to reconstruct.
Surgery for Advanced Hypopharyngeal Cancers
Surgery for hypopharyngeal cancer involves the larynx as well as the hypopharynx. e
larynx is usually entirely removed unless the lesion is lateralised. e pharynx is usually
328 Head and Neck
HYPOPHARYNX
not in
Near total la
Surgery is advocated for:
Good general condition/PS
Involved laryngeal framework
Surgery is contraindicated for:
Poor general condition/PS
Metastatic disease
Compromised laryngeal function then it
should be removed to allow airway protection
Disease extension to areas of unresectability
or poor feasibility: root of neck, prevertebral
Salvage surgery following radiation or
concurrent chemoradiation
involvement, superior extension into the
oropharynx, lateral extension involving
carotid artery (T4b)
Figure 63.3 Arguments for and against surgery in advanced disease.
resected either partially or circumferentially, and most patients will need appropriate reconstruction to restore pharyngeal continuity and minimise the risk of pharyngocutaneous stulae. Adjuvant radiation/chemoradiation is an essential part of the multimodal therapy for
stage III/IV hypopharyngeal cancers treated surgically. Pros and cons of surgery in advanced
hypopharyngeal cancer are shown in Figure 63.3.
Surgical Procedures for Advanced Hypopharyngeal Cancer
Figure 63.4 shows the surgical options for advanced hypopharyngeal cancer as well as recon-
struction options.
Surgery for advanced hypopharyngeal cancer
ryngectomy with
partial pharyngectomy
Voice conservation with
tracheostome but does not
maintain nasal respiration
Limited role as need
lateralised cancer that does
volve PC mucosa or the
intra-arytenoid region.
Primary closure
Total laryngectomy
with pharyngectomy
(Partial or circumferential)
Performed if inter-arytenoid or
PC involvement
Assessment of pharyngeal mucosa
(not under tension or stretched)
To dictate need for
reconstruction
3 cm or less mucosa>3 cm
3 to 1 cm <1 cm
Patch reconstructionCircumferential reconstruction
Free ap
RFF or ALT
Pedicled Free ap
major
Jejunum or tubed
ALT or tubed RFF
Pectoralis
Pedicled
Pectoralis
major
Pharyngo-laryngo-
oesophagectomy
with gastric pull up
If the PC lesion extends to the
cricopharyngeous or upper
oesophagus
Allows a single stage
vascularised reconstruction with
anastomosis in the neck. It is
well documented that this has a
higher mortality than the other
operative interventions.
Figure 63.4 Surgical options for hypopharyngeal cancer (RFF = radial forearm ap, ALT = antero-
lateral thigh).
Head and Neck 329
OROPHARYNX
Management of Neck Disease in Advanced Hypopharyngeal Cancer
In stage III and IV cancers, the patient either has manifest neck nodes (N1–N3) or has
advanced primary (T3/T4) tumour. With neck nodes, the surgical plan is usually bilateral
neck dissection at Levels II–V. In patients with advanced primaries and no neck nodes, the
surgical plan will entail bilateral neck dissection at Levels II–IV. e neck dissection needs to
be tailored to individual disease, with consideration of retropharyngeal nodes.
Adjuvant Therapy
Following surgery in advanced stage III and IV hypopharyngeal cancers, adjuvant therapy
with either radiation therapy or concurrent chemoradiotherapy is an essential part of the
treatment protocols.
Disease Surveillance
e patients should be monitored for second primary cancers in the upper aerodigestive
tract; second primaries are seen in up to 50% of patients.
KEY POINTS
• Accurate staging is essential. Workup should include evaluation for synchronous
primaries and distant metastasis.
• Laryngeal function should be accurately evaluated prior to treatment, especially while
considering organ preservation.
• Unimodality treatment is recommended for stage I and II disease.
• Multimodality treatment is recommended for stage III and IV disease.
• The overall 5-year, tumour-specic survival is less than 30%, although the survival of
treated patients rises to 50%.
Further Reading
Garneau JC, Baskt RL, Miles BA. Hypopharyngeal cancer: A state of the art review. Oral
Oncology 2018; 86: 244–250.
Paleri C, Rollands NJ. (Eds.) Head and Neck Cancer: United Kingdom National
Multidisciplinary Guidelines, 5th edition, 2016.
64. OROPHARYNX
Introduction
ere has been a rapid increase in the incidence of human papillomavirus (HPV)-associated
oropharyngeal squamous cell carcinoma (HPV+ OPSCC) over several decades. is disease
entity presents in younger, tter, more auent patients who drink less alcohol and smoke
less tobacco than patients who present with HPV-negative disease (HPV– OPSCC). HPV+
tumours typically present with multiple cervical lymph nodes (with a high prevalence of
extracapsular spread), but they respond more favourably to treatment. OPSCC treatment
results i n high levels of ea rly and long-term toxicity; c onsequently, greater numbers of youn ger
patients are cured of their disease but are le with poor swallowing outcomes. Although
most patients with HPV+ OPSCC do well, a subgroup of patients still do poorly. ere is an
urgent need to nd novel de-intensied treatments that maintain the advantageous survival
outcomes but confer better swallowing outcomes for patients with HPV+ OPSCC, as well as
dening treatments that will improve survival for patients with HPV– OPSCC.
330 Head and Neck
OROPHARYNX
Surgical Anatomy of the Oropharynx
e pharynx is divided into three parts: the nasopharynx, oropharynx, and hypopharynx.
e oropharynx is bounded superiorly by the so palate, inferiorly by the lingual surface
of the epiglottis, anteriorly by the palatoglossal arches and vallate papillae of the tongue, and
laterally by the pharyngoepiglottic folds. e section of posterior pharyngeal wall included
in the oropharynx lies anterior to the vertebral bodies of C2/C3 and extends from a horizontal line drawn through the hard palate cranially to a horizontal line drawn through the
hyoid bone caudally.
Surgical access to the structures of the oropharynx may be achieved transorally, anteriorly
via mandibulotomy, or inferiorly and laterally from the neck.
Tumours of the Oropharynx
Apart from mucous retention cysts of the vallecula/tonsil and papillomas, benign oropharyngeal tumours are rare. Deep lobe parotid tumours, commonly pleomorphic salivary adenomas, while not strictly tumours of the oropharynx, may present as an asymmetric mass
protruding into the pharynx and/or so palate. us, peritonsillar bulging in the absence of
infective symptoms should not be confused with quinsy, and instead should be suspected to
be a deep lobe parotid tumour.
Lymphomas in the oropharynx are rare and are almost exclusively non-Hodgk in lymphomas
arising in the lymphoid tissue of the palatine tonsil or base of tongue (BOT).
Sali vary gla nd cancers acc ount for up to 6% of all head and neck m aligna ncies. Approximately
20% of all salivary gland tumours arise in the minor salivary glands (MiSG), and they are
malignant 80% of the time. e most common sites of such tumours are the hard and so
palate, and the four most common malignant subtypes are mucoepidermoid carcinoma,
adenoid cystic carcinoma, adenocarcinoma, and salivary duct carcinoma. Surgical resection with adequate surgical margins is the primary treatment of choice. Post-operative
radiotherapy (RT) is used, particularly in patients with high-risk factors (T3/4, close/
involved margins, high-grade tumour, perineural/perivascular invasion, and N+ disease),
although the radiosensitivity of MiSG cancers is highly variable.
Oropharyngeal Squamous Cell Carcinoma (OPSCC)
Squamous cell carcinoma is the most common malignancy presenting in the oropharynx.
While alcohol and tobacco use are well documented individual and synergistic risk factors
for the development of head and neck SCC, evidence conrms that HPV, specically genotype 16, is an additional independent risk factor for OPSCC.
Two diagnostic strategies are commonly used to detect HPV DNA within tumour cells—in
situ hybridization (ISH) and polymerase chain reaction (PCR). Contamination or previous
infection could render tests positive without conrming downstream biological activity of
HPV; therefore, quantitative reverse transcription PCR (qRT-PCR) and RNA-based chromogenic ISH (RNA-ISH) can be used. More oen, however, immunohistochemistry of p16 overexpression is used as a surrogate marker, although up to 30% of p16-positive tumours are HPV
negative. Immunohistochemistry is inexpensive and widely available and is well established
in treatment protocols. e overexpression of p16 correlates well with clinical outcome.
Clinical Presentation
It is recognized that the presentation of HPV+ OPSCC diers signicantly from that of
HPV– OPSCC. HPV+ OPSCC typically presents with a small primary tumour and multiple,
enlarged, cystic cervical lymph nodes as well as a high prevalence of extracapsular spread
(ECS). In contrast, HPV– OPSCC presents as a more typical head and neck cancer, with
larger primary tumours and relatively lower tumour burden in cervical lymph nodes. In
OPSCC, 60% of tumours arise in the tonsil and 30% in the BOT.
Local extension of OPSCC can give rise to a range of symptoms, including odynophagia, persistent throat pain, referred otalgia, dysphagia, altered speech, impaired tongue movement,
Head and Neck 331
OROPHARYNX
and bleeding. Incidental discovery of painless enlarged cervical lymph node(s) is a very common presentation, especially for HPV+ OPSCC. If the presenting lymph node is solitary, it is
commonly in Level II, while multiple involved lymph nodes will present as a chain extending
from Level II to Level IV.
Clinical Examination
Patients require a thorough examination of the upper aerodigestive tract (UADT), with
inspection of the oral cavity and oropharynx and transnasal exible breoptic endoscopy.
High-quality clinical photographs are important for recording pertinent clinical ndings.
Examine the neck thoroughly to determine the presence of lymph node involvement as well
as the nodes’ size, consistency, and mobility.
Investigations
Cross-sectional imaging—computed tomography(CT) or magnetic resonance imag-
•
ing (MRI)—of the head and neck.
CT scan (or PET CT) of the thorax and upper abdomen.
•
Examination under anaesthesia (EUA) of the UADT and biopsy of the presenting pri-
•
mary tumour.
Ultrasound (US) of the neck if enlarged nodes are identied and US ne-needle aspi-
•
ration cytology (FNAC) of any suspicious neck nodes.
Management
e management of oropharyngeal carcinoma is challenging. HPV status is highly prognostic in OPSCC patients treated with chemoradiotherapy (CRT): 3-year overall survival
is 82.4% in HPV+ cancer, compared to 57.1% in HPV– cancer. Currently, HPV+ and HPV–
OPSCC are managed using the same treatment protocols, but the improved prognosis
associated with HPV positivity highlights the need for de-intensied treatment strategies that maintaining the patients’ survival outcomes. Treatment intensication is also
needed to enhance survival in patients with HPV– OPSCC and the subgroup of patients
with HPV+ OPSCC who do badly. At present, there are no high-quality data comparing
surgical and non-surgical approaches, and RT and CRT are the accepted standards of
care in many centres throughout the world for early and late-stage OPSCC, respectively.
In general, the treatment options are:
For T1–T2 N0: Radical RT or transoral surgery and neck dissection (with post-opera-
•
tive CRT if there are adverse pathological features on histology)
For other stages: primary CRT or surgery and adjuvant (chemo)radiotherapy
•
Radiotherapy (RT)/Chemoradiotherapy (CRT)
e rationale for the use of RT or CRT in treating OPSCC is functional organ preservation while
achieving high cure rates. Early-stage T1–T2 N0–N1 OPSCC can be eectively treated with RT
alone (70 Gy in 35 fractions). For more advanced T and/or N stage OPSCC, CRT is the standard
of care, with a RT dose equivalent of 70 Gy delivered in 35 fractions together with concurrent cisplatin at a dose of 100 mg/m2 given on days 1, 22, and 43 of the schedule. Radical RT may be given
alone to patients with advanced disease who are not t for concurrent treatment, particularly
if they are more than 70 years old, when the benets of concurrent chemotherapy are reduced.
e dose of adjuvant RT aer surgery in head and neck cancers is 57.6 Gy to the primary site
with up to 63 Gy to areas of ECS. RT should begin ideally within 5 weeks and no later than 6
weeks post-operatively. e indications for post-operative RT and CRT for OPSCC depend on
pathological risk factors for recurrence and include primary tumour factors, such as close (1–5
mm) or positive (<1 mm) margins, T3–4 stage, and perineural and/or lymphovascular invasion,
and nodal factors, such as ECS of nodal disease and/or N2–N3 nodal stage. Patients with ECS
and/or microscopically involved (<1 mm) surgical resection margins experience signicant benet in terms of overall and disease-free survival from post-operative CRT compared to RT alone.
332 Head and Neck
OROPHARYNX
Transoral Surgery (TOS)
Transoral laser microsurgery (TLM) and transoral robotic surgery are minimally invasive
surgical techniques for T1–T3 tumours with considerably less long-term functional decit
than open surgery. TOS is usually performed with neck dissection, either simultaneously
or as a staged procedure. Adjuvant treatment is required in most patients, usually due to
advanced nodal disease.
TOS is generally well tolerated, with a median length of hospital stay of approximately
4.4 days. Acute complications include haemorrhage (2.4%) and stula (2.5%). Temporary
tracheostomy tubes are needed in 12% of patients at the time of surgery but most are decannulated prior to discharge. Temporary nasogastric tubes are required in up to 47% of patients
post-operatively but most patients can manage an oral diet by 4 weeks aer surgery. Longterm functional outcomes aer TOS appear favourable in small studies.
Transoral Robotic Surgery (TORS)
Currently, the daVinci® Surgical System is the most popular platform for robotic surgery.
It consists of three parts: a ‘patient-side’ that cart deploys surgical instruments within the
patient’s body; a ‘surgeon’s console’, which is remotely placed where three-dimensional display, foot pedals to control cautery, and hand controls for the instruments are found; and the
‘vision cart’, which houses the video processor and screens to project the procedure to the
operating assistant and other observers.
Despite evidence supporting the safety and feasibility of TORS, there are no randomised
studies comparing oncological outcomes of surgery versus CRT for OPSCC to date.
Free ap inset with the robot transorally aer orophary ngectomy can now also be performed.
Management of the Neck
In the clinically/radiologically N0 neck, the prevalence of micrometastatic nodal disease
is between 10% and 30%; therefore, elective treatment of the neck is recommended by
either a selective neck dissection or RT. With surgery, dissection of Levels II, III, and possibly Level IV should be performed. In N0 necks, lateralised tumours require an ipsilateral
neck dissection, with non-lateralised tumours needing a contralateral neck dissection for
pathological staging purposes only. In N+ necks undergoing surgery, it is usual to dissect
Level IIb.
Treatment Failure
Signicantly more locoregional relapse is found in the HPV– OPSCC group than in the HPV+
OPSCC group, although the rate of distant metastasis does not dier signicantly between the
groups. e most common pattern of distant spread is to the lung, bone, and liver.
KEY POINTS
• The incidence of oropharyngeal cancer is increasing, and most of the increase is
attributable to a rise in HPV-related disease (HPV+).
• HPV+ oropharyngeal squamous cell carcinoma (HPV+ OPSCC) constitutes a discrete
disease entity, presenting in patents who are younger than patients presenting with
HPV– disease.
• Despite presenting with clinicopathological features usually associated with poor
disease outcome (N+ with ECS), HPV+ tumours respond better to treatment.
• Attention has turned to potential de-intensied treatment strategies for HPV+ OPSCC,
in order to maintain advantageous survival outcomes whilst reducing treatmentrelated early and long-term toxicity.
• Signicant expertise exists in transoral robotic surgery (TORS) for oropharyngeal
surgery, and several ongoing randomised trials will clarify the role of this modality in
head and neck cancer treatment.
Head and Neck 333
NASOPHARYNGEAL CARCINOMA
Further Reading
1. De Almeida JR, Byrd JK, Wu R, et al. A systematic review of transoral robotic surgery
and radiotherapy for early oropharynx cancer: a systematic review. Laryngoscope 2014;
124: 2096–3002.
2. Howard J, Masterson L, Dwivedi RC, et al. Minimally invasive surgery versus radiotherapy/chemoradiotherapy for small-volume primary oropharyngeal carcinoma.
Cochrane Database Syst Rev 2016; 12 CD010963.
3. Holsinger FC, McWhorter AJ, Menard M, et al. Transoral lateral oropharyngectomy
for squamous cell carcinoma of the tonsillar region: I. Technique, complications, and
functional results. Arch Otolaryngol Head Neck Surg 2005; 131: 583–591.
65. NASOPHARYNGEAL CARCINOMA
e nasopharynx is situated deep inside the head, and carcinoma arising in the epithelium
of the nasopharynx has a dierent aetiology, epidemiology, and biology than other cancers
of the upper aerodigestive tract.
Epidemiology
e incidence of nasopharyngeal carcinoma demonstrates one of the largest geographical variations among all head and neck cancers, and the incidence in endemic areas can be
50 times higher than in low-prevalence areas. e highest incidence is found in Southern
China, including Taiwan, Hong Kong, and Macau. Migrants originati ng from high-incidence
areas also have a high incidence of nasopharyngeal carcinoma, although the risk decreases
in second- or third-generation ospring of migrants. Populations from Malaysia, Indonesia,
Arabia, North Africa, ailand, and the Philippines, as well as Inuits, have intermediate
incidence of nasopharyngeal carcinoma. Caucasians and populations from Northern China
and East Asia have a low incidence.
Aetiology
Consumption of salted sh and eating preserved foods, especially at a young age, are aetiological factors. Smokers have a moderate increase in risk. e aetiology of nasopharyngeal
carcinoma is the result of a complex interplay of genetic factors, early latent infection by
Epstein–Barr virus (EBV) as well as subsequent EBV reactivation, and exposure to environmental carcinogens.
EBV is found only in the poorly dierentiated and undierentiated forms of nasopharyngeal
carcinoma, which are the prevalent subtypes in high-incidence areas. e exact role of EBV in
the development of nasopharyngeal carcinoma is still unknown. It is postulated that the combination of genetic susceptibility, environmental factors, and EBV infection all contribute.
Pathology
e most common histological form of nasopharyngeal cancer in endemic areas is the nonkeratinising type. e histology of keratinising squamous cell carcinoma (SCC) is similar
to that of other SCC in the upper aerodigestive tract. However, the non-keratinising type
has some distinctive histological features. e malignant cells are inltrated with lymphocytes and plasma cells; the term lymphoepithelial carcinoma is used to describe this.
Lymphoepithelial carcinoma can also be found in salivary glands, paranasal sinuses, and
lungs. When lymphoepithelial carcinoma is found outside the nasopharynx, it is important
to distinguish between primary cancer and metastatic nasopharyngeal carcinoma.
334 Head and Neck
NASOPHARYNGEAL CARCINOMA
EBV is ubiquitous in all the cancer cells in non-keratinising nasopharyngeal carcinoma.
Immunostaining for EBV in cancer cells can help to dierentiate between nasopharyngeal
carcinoma and dierent types of head and neck cancer, especially in tissue obtained from
metastatic lymph nodes. Immunostaining for EBV-encoded small ribonucleic acid (EBER) is
commonly used to detect EBV inside the cancer cells.
Other cancers that occur in the nasopharynx include salivary gland carcinomas, sarcomas,
lymphomas, and malignant melanomas.
Clinical Features
Early cancers of the nasopharynx produce minimal and trivial symptoms. Local features can
be divided into nasal, otological, cervical, and neurological ndings. Common nasal sy mptoms
are blood-stained nasal discharge, post-nasal drip, obstruction, cacosmia, or a smell of blood.
Otological symptoms are usually caused by Eustachian tube dysfunction (i.e. ipsilateral
hearing loss, tinnitus, and sensation of blockage). Otoscopic examination reveals a middle
ear eusion. e nasopharynx should always be examined in adults with unexplained persistent middle ear eusion.
An enlarging upper neck mass is the most common reason for patients to be referred. Up to
70% of patients have enlarged neck lymph nodes on presentation (most frequently Level II
and upper Level V). Lymphatic spread occurs in an orderly fashion from superior to inferior,
with skip metastases rare.
Nasopharyngeal carcinoma patients can present with metastatic neck lymph nodes from an
unknown primary. Imaging modalities like magnetic resonance imaging (MRI) and positron emission tomography (PET) may reveal the presence of a small cancer in the nasopharynx. Testing for EBV can also point to a nasopharyngeal primary.
Neurological symptoms include headache (usually vertex or occiput), facial pain, midface
numbness, cranial nerve palsies (most commonly V2, V3, and VI). Rarely, patients present
with ophthalmoplegia, decreased vision, and proptosis.
Diagnosis
A full head and neck examination is essential in all patients. Care should be taken to look for
otitis media with eusion, cranial nerve palsies, and cervical lymphadenopathy.
Antegrade nasopharyngoscopy should be performed with either a rigid or a exible endoscope. Most of the cancers are readily apparent under endoscopy, presenting as a mass with
abnormal capillaries on the surface and with areas of ulceration (Figure 65.1).
Once a tumour is identied, biopsy of the lesion can usually be performed concurrently or
under general anaesthesia (Figure 65.2).
Figure 65.1 View of a tumour in the left nasopharynx through a 0 rigid nasoendoscope.
Head and Neck 335
NASOPHARYNGEAL CARCINOMA
Figure 65.2 Biopsy of the left nasopharynx.
Laboratory Tests
Serum EBV IgA antibiodies against viral capsin antigen, early antigen, and EBV nuclear
antigens are elevated in patients with nasopharyngeal carcinoma and can be used as tumour
markers in screening for the cancer. ese serological markers are not useful for monitoring
of treatment ecacy and screening for recurrence. Plasma EBV DNA is a more sensitive and
specic tumour marker for nasopharyngeal carcinoma that is useful for prognostication,
monitoring of treatment response, and screening for tumour recurrence.
Imaging
MRI is the imaging modality of choice for delineating the extent of disease in the skull base.
CT is useful in detecting cortical bone erosion in the skull base but cannot oen dierentiate
between normal structures and tumour invasion in the skull base. PET CT is a useful adjunct
to delineate the extent of disease, nodal metastasis, and distant metastasis.
Staging
Nasopharyngeal carcinoma has biological behaviour and prognosis vastly dierent from
SCC of the head and neck region, and the staging system for it is also dierent (see Staging
of Head and Neck Cancer).
Primary Treatment
Non-Surgical Treatment
Radiotherapy is the cornerstone of locoregional treatment for all stages of nasopharyngeal carcinoma without distant metastases. Early-stage disease, including stage I and low-risk stage II
nasophar yngeal carcinoma, can be treated with radical radiotherapy alone. Stage II disease with
higher tumour load and stage III or IV disease require combination chemotherapy and radiotherapy. e current standard of care for advanced nasopharyngeal carcinoma is concurrent
cisplatin during radiotherapy followed by adjuvant cisplatin and uorouracil. Epidermal growth
factor receptor tyrosine kinase inhibitors like cetuximab have not been shown to be benecial.
Intensity-modulated radiotherapy (IMRT) is the standard of care for radiation treatment of
nasopharyngeal carcinoma. With IMRT, local control rates of over 90% have been reported.
e complications of conventional two-dimensional radiotherapy, such as hearing loss,
xerostomia, temporal lobe neuropathy, trismus, and neck brosis, are reduced.
Salvage Treatment
Salvage treatment for nasopharyngeal carcinoma is moderately successful but with signicant morbidities. Because patients with recurrences have already been exposed to the toxicities of previous treatment, the choice of the salvage treatment needs to take into account the
tolerance of the normal tissue.
336 Head and Neck
NASOPHARYNGEAL CARCINOMA
Radiotherapy for Local Failures
Radiotherapy for local failures can be delivered by external beam or by local brachytherapy.
e main limiting factor in re-irradiation is the radiation tolerance of vital organs like brainstem, optic chiasma, and temporal lobe.
Brachytherapy delivers a high dose of radiation with limited penetration inside the nasopharynx to treat local failures without deep invasion.
Surgery for Local Failure
e nasopharynx is notoriously dicult to access surgically. Most routes of access require
facial incisions and multiple osteotomies and transgress a signicant amount of normal tissue to expose the nasopharynx. erefore, surgical resection of the nasopharynx,
namely nasopharyngectomy, is reserved for salvaging radiation failures. e decision
to oer nasopharyngectomy for salvaging local failures depends on the location of the
tumour and the general condition of the patient. Tumours that show internal carotid artery
encasement, extensive skull base inltration, or intracranial extension are not suitable for
salvage surgery.
Surgical approaches to the nasopharynx include the transpalatal (inferior) approach, the
transcervico-mandibulo-palatal approach, the midfacial degloving (anterior) approach, the
maxillary swing (anterolateral) approach (Figure 65.3), the facial translocation (anterolateral) approach, the lateral skull base approach, the endoscopic-endonasal approach, and
robot-assisted approaches.
Figure 65.3 (a) Weber-Ferguson-Longmire incision and (b) view after swinging the maxilla laterally.
Head and Neck 337
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