Evaluation and Management of Oropharyngeal Carcinoma Flashcards
What are the two most important risk factors
associated with the development of oropharyngeal
squamous cell carcinoma?
HPV infection and tobacco smoking. Traditional risk factors
for head and neck squamous cell carcinoma are still relevant
(see Oncology section).
Which HPV subtypes are associated with an
increased risk of oropharyngeal squamous cell
carcinoma?
HPV 16 (predominant), 18, 31, and 33
What is the most common malignancy of the
oropharynx?
Squamous cell carcinoma
What rare malignancy arising in the oropharynx
(most commonly in the tonsil and base of tongue)
is a poorly differentiated squamous cell carcinoma
or undifferentiated carcinoma associated with a
reactive lymphoplasmacytic infiltration?
Lymphoepithelial carcinoma
What is the most common type of lymphoma
found in the oropharynx?
Non-Hodgkin lymphoma. Diffuse large B-cell lymphomas
are the most common subtype.
What percentage of extranodal head and neck
lymphomas are found in the Waldeyer ring?
36%
What locally aggressive oral and cutaneous vas-
cular malignancy can be found in the oropharynx
(primarily soft palate) in AIDS patients?
Kaposi sarcoma
What are the two most common salivary gland
malignancies that arise in the oropharynx?
They arise from minor salivary glands most commonly in
the soft palate, tonsil, and base of tongue:
● Adenoid cystic carcinoma (cylindromatous or cribriform)
● Mucoepidermoid carcinoma
What malignant tumor can rarely arise from
melanocytes in the mucosa of the oropharynx?
Malignant mucosal melanoma
What are common initial symptoms of oropharyngeal malignancy?
Odynophagia, referred otalgia, dysphagia, speech distortion, globus, bleeding, painless neck mass
Why might patients with oropharyngeal cancer
often be initially diagnosed with stage III or IV
disease?
Vague symptoms that are often experienced in benign
disease processes
If a patient with oropharyngeal cancer develops
severe trismus, what might this indicate?
Invasion into the masseteric space with involvement of the
pterygoid musculature
A patient has a palpable mass centered in the right
base of the tongue. On tongue protrusion, you note
hemitongue atrophy and fasciculations on the right.
Which nerve is likely involved by the tumor?
Hypoglossal nerve
What adjuvant physical examination tool should be used when there is concern for an orophar-
yngeal malignancy?
Flexible endoscopy; evaluate for tumor extension, status of
the larynx, etc. Mirror should be considered if flexible
endoscopy is not available or as an adjunct to flexible
endoscopy.
In addition to direct visualization of the anatomy,
what important physical examination maneuver
should be performed in patients with possible
oropharyngeal cancer?
Digital palpation for submucosal disease, friability, and
mobility. Palpation of the neck is also imperative.
What structure(s) are potentially involved if a
patient presents with an immobile oropharyngeal
tumor?
● Medial pterygoid muscle ● Mandible ● Maxillary tuberosity ● Hyoid bone ● Parapharyngeal structures
Tumors in which oropharyngeal subsite is most commonly diagnosed by visual inspection at ear-
lier stages?
Soft palate. They generally occur on the anterior oropharyngeal surface of soft palate.
What patient specific/anatomical factors identified
on physical examination may indicate that a
patient with an oropharyngeal tumor is a poor
candidate for a transoral procedure?
● Severe trismus due to tumor invasion or fibrosis ● Narrow mandibular arch ● Crowded oral cavity, making displacement of the soft tissues challenging ● Long incisor teeth ● High body mass index ● Retrognathic ● High Mallampati score ● Mandibular tori
What tumor specific factors can be identified on
physical examination, which would suggest that a patient is a good candidate for transoral surgery?
● Exophytic
● Mobile
● Proximal oropharynx
● No evidence of involvement of deep structures such as the mandible, pterygoid musculature, maxillary tuber-
osity, hyoid bone, or parapharyngeal structures
● Predicted resection < 50% of the base of tongue or < 75%
of the soft palate
Describe the tumor specific contraindications to
transoral tumor resection for an oropharyngeal
tumor.
● Invasion of the skull base
● Invasion or encasement of the great vessels
● Invasion of the mandible
● Confluent primary tumor and neck metastasis
● Tumor extension potentially necessitating an R1 or R2
resection.
How is T4a oropharyngeal cancer defined?
Moderately advanced local disease: Tumor invades larynx,
extrinsic tongue musculature (genioglossus, hyoglossus,
styloglossus, palatoglossus), medial pterygoid muscle, hard
palate, or mandible
How is T4b oropharyngeal cancer defined?
Very advanced local disease: Tumor invades lateral pter-
ygoid muscle, pterygoid plates, lateral nasopharynx, skull
base, or encases the carotid.
With regard to tongue-base tumors, does mucosal
extension of a tumor to the lingual surface of the
epiglottis constitute invasion of the larynx and T4a
status?
No
True or False. Nodal metastases to level VII
(superior mediastinal lymph nodes: between the
common carotid arteries laterally, superior border
of manubrium, and innominate artery) are not
considered distant metastases.
True
Currently, there is no widely accepted staging
system that takes into account HPV status of an
oropharyngeal tumor. However, the NCCN (2013)
does recommend HPV testing to better define
prognosis. What test is currently recommended?
Immunohistochemical staining for p16
Note: The best test to diagnose HPV status is controversial.
What prognostic role does HPV positivity play in
oropharyngeal squamous cell carcinoma?
Improved disease-free survival and overall survival when
compared with HPV-negative oropharyngeal squamous cell
carcinoma
What are the adverse features identified by the
NCCN (2013) for oropharyngeal cancer?
● Extracapsular nodal spread ● Positive margins ● pT3 or pT4 primary ● N2 or N3 nodal disease ● Nodal disease in levels IV or V ● Perineural invasion ● Vascular embolism
What treatment modalities does the NCCN (2013)
recommend for patients with T1–2, N0–1 oro-
pharyngeal cancer?
● Definitive radiation therapy
● Surgical resection of the primary ± ipsilateral or bilateral
neck dissection as indicated; additional intervention
based on adverse features:
○ None → no additional intervention
○ One positive node, no adverse features consider
radiation therapy
○ Positive margin → Reexcision or radiation therapy (CRT
for T2)
○ Extracapsular spread→CRT
○ Other risk feature → radiation therapy ± concomitant
chemotherapy
○ T2N1: Consider primary chemoradiation therapy
What treatment modalities does the NCNN (2013)
recommend for patients with T3–4a, N0–1 or-
opharyngeal cancer?
● Concurrent chemoradiation therapy with cisplatin (cat-
egory 1, preferred)
● Surgical resection of the primary ± ipsilateral or bilateral
neck dissection as indicated; additional intervention
based on adverse features:
○ None → Radiation therapy
○ Extracapsular spread and or positive margin → Che-
moradiation therapy
○ Other risk feature → radiation therapy ± concomitant
chemotherapy
○ Induction chemotherapy + radiation therapy ± con-
comitant chemotherapy
○ Multimodality clinical trials
What treatment modalities does the NCCN (2013)
recommend for patients with any T, N2–3
oropharyngeal cancer?
● Concurrent chemoradiation therapy with cisplatin ± neck
dissection for residual nodal disease
● Induction chemotherapy + radiation therapy ± chemo-
therapy
● Surgical resection of the primary ± ipsilateral or bilateral
neck dissection as indicated; additional intervention
based on adverse features:
○ None → no additional intervention (N1 only)
○ Extracapsular spread and/or positive margin → che-
moradiation therapy
○ Other risk feature → radiation therapy ± concomitant
chemotherapy
○ Multimodality clinical trials
For all stages of oropharyngeal cancer, if there is
residual disease with radiation therapy ± concom-
itant chemotherapy, what intervention is recom-
mended?
Salvage surgery
What radiation technique or modality is recommended for management of oropharyngeal tumors?
Intensity modulated radiation therapy (IMRT)
What does the NCCN (2013) recommend for
definitive radiation therapy for oropharyngeal
cancer?
● Conventional fractionation: 66 to 74 Gy, daily Monday
through Friday for 7 weeks
● Altered fractionation:
○ Accelerated: 66 to 74 Gy to gross disease, 44 to 64 Gy
to occult disease; six fractions/week
○ Concurrent boost accelerated: 72 Gy, daily + twice daily
for last 12 treatments, for 6 weeks
○ Hyperfractionation: 81.6 Gy, twice daily, Monday
through Friday, for 7 weeks
When considering concurrent chemoradiation
therapy, what amount of energy does the NCCN
(2013) recommend for (1) primary disease, (2)
gross adenopathy, and (3) occult adenopathy?
Conventional fractionation
● ≥ 70 Gy
● ≥ 70 Gy
● 44–64 Gy
What does the NCCN (2013) recommend for
adjuvant radiation therapy after primary surgical
intervention for oropharyngeal cancer?
Conventional fractionation
● 60 to 66 Gy to the primary and gross nodal disease
● 44 to 64 Gy to occult nodal disease for 6 weeks
What is the recommended radiation target vol-
ume of the neck in patients with oropharyngeal
squamous cell carcinoma and ipsilateral N2a or
N2b disease?
Levels IB-V and retropharyngeal lymph nodes
What chemotherapy regimen is recommended for
concurrent chemoradiation therapy in orophar-
yngeal squamous cell carcinoma?
Cisplatin: 100 mg/m2 every 3 weeks x three doses
What surgical approach can be used for most early
and some advanced oropharyngeal malignancies?
Transoral approach, including laser microsurgery or robotic
surgery
What surgical approach can be used for more
extensive inferiorly located oropharyngeal tumors
not amendable to transoral approaches and does
not require mandibulotomy?
● Lateral pharyngotomy
● Transhyoid pharyngotomy
● Lingual release and pull-through technique
What surgical approach can be used for the most
advanced oropharyngeal lesions often requiring
reconstruction?
Mandibulotomy with mandibular swing
Similar to the management recommendations for
oral cavity cancers, what options are available for
surgical management of oropharyngeal tumors
that invade the mandible?
● Periosteal or superficial cortical invasion only: Rim
mandibulectomy
● Medullary invasion: Segmental mandibulectomy
See oral cavity malignancy for additional discussion of
mandibulectomy indications.
How should retropharyngeal lymph nodes be addressed in patients with advanced oropharyngeal squamous cell carcinoma?
Retropharyngeal lymph node dissection and/or radiation
therapy
When performing transoral lateral oropharyngectomy or base-of-tongue resection, in addition to clipping named vessels in the operative field with
two or three clips and meticulous hemostasis,
what additional procedures should be considered
to decrease the risk of postoperative hemorrhage?
Ligation of vessels at risk for bleeding into the oropharynx
(lingual, facial, and superior laryngeal arteries; some
authorities consider tying off the external carotid system).
This can be done during concomitant neck dissection or as
a separate procedure.
What is the most common method used for
reconstruction of oropharyngeal defects after
transoral procedures?
None: The wound is allowed to heal by secondary intention.
If a patient undergoes transoral tumor extirpation
for a primary base-of-tongue or tonsil tumor at the
same time as a neck dissection, and the decision is
made to allow the wound to heal by second
intention, what should be carefully ruled out
before closure of the neck?
Orocervical fistula
What is the best reconstructive option for large
oropharyngeal defects involving the tonsillar fossa,
pharyngeal wall, and tongue base?
Fasciocutaneous free flap (radial forearm free flap is used
most commonly)
What are the most important goals of tongue base
reconstruction?
● Maintenance of the airway with prevention of aspiration
● Preservation of swallowing
● Preservation of speech
When considering a pectoralis major myocuta-
neous flap or a fasciocutaneous free flap for reconstruction of the oropharynx, which recon-
structive option provides the best functional out-
come with respect to swallowing?
Free flap reconstruction (decreased percutaneous endo-
scopic gastrostomy tube dependence)
Although multiple reconstructive options are
available for soft palate reconstruction, including
primary closure, local mucosal flaps, and free
tissue transfer, what additional option should be
considered for smaller defects, and what healing
process may contribute to decreased velopharyngeal insufficiency over time?
● Healing by second intention
● Cicatricial scarring
What might result if a large portion of the soft
palate is resected and not reconstructed after
surgery for oropharyngeal tumors?
Velopharyngeal insufficiency with nasopharyngeal reflux
and hypernasal speech
