Oral cavity
Squamous cell carcinoma
Oropharynx

Author: Anshu Jain, M.D. (see Authors page)

Revised: 25 April 2018, last major update April 2014

Copyright: (c) 2004-2018, PathologyOutlines.com, Inc.

PubMed Search: Squamous cell carcinoma[TI] oropharynx[TI] free full text[sb]

Cite this page: Jain, A. Squamous cell carcinoma - oropharynx. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/oralcavitysccoropharynx.html. Accessed August 17th, 2018.
Definition / general
  • < 1% of all newly diagnosed cancers and 10 - 12% of cancers in head and neck
Anatomy
  • Palatine arch (superior oropharynx): soft palate, uvula, anterior tonsillar pillars and retromolar trigone
  • Oropharynx boundaries:
    • Anterior: posterior 1/3 of tongue, vallecula, lingual epiglottis
    • Lateral: palatine tonsils or tonsillar fossa, posterior tonsillar pillars, glossotonsillar sulcus
    • Posterior: posterior and lateral oropharyngeal walls from soft palate to hyoid bone, including pharyngoepiglottic fold
Epidemiology
  • Age: sixth - seventh decade (tobacco and alcohol associated cases) vs. fourth - fifth decade (HPV associated cases, although even pre-HPV, rare cases did occur, Otolaryngol Head Neck Surg 1999;120:828)
  • Gender: male > female (tobacco and alcohol) vs. male = female (HPV)
  • Behavior: tobacco and alcohol consumption, HPV 16, marijuana
Sites
  • Most common site is base of tongue
  • Tends to extend to lymph nodes in levels II, III and IV of neck
  • Higher susceptibility for retropharyngeal nodal disease with lesions along posterior pharyngeal wall or palatine tonsil
  • Locoregional spread is typically ipsilateral to the primary site of malignancy; bilateral neck disease can also occur with cancers on the tongue base, soft palate and posterior pharyngeal wall
Pathophysiology
  • HPV may exert its carcinogenic effect by integrating its genome into a host cell nucleus by expressing E6 and E7 oncoproteins and inactivating the tumor suppressing p53 and retinoblastoma proteins
Diagrams / tables

Images hosted on other servers:

Head and neck anatomy

Clinical features
  • Pain or sore throat, dysphagia and odynophagia
  • Referred otalgia, voice changes, hemoptysis
  • May present only with a neck mass
Grading
  • Grade 1: Well differentiated
  • Grade 2: Moderately differentiated
  • Grade 3: Poorly differentiated
  • Grade X: Cannot be assessed
Staging / staging classifications
TNM staging:
Prognostic factors
Case reports
Treatment
  • Single modality treatment is acceptable for small primary lesions (T1 or T2) or for low neck disease (N0 or N1); combined treatment, such as chemoradiotherapy or surgery with adjuvant radiotherapy, is warranted for higher tumor burdens
  • Radiotherapy with surgery as salvage yields 5 year locoregional control of 60 - 76% and 5 year overall survival of 43 - 52% (Int J Radiat Oncol Biol Phys 1996;34:289, Cancer 2002;94:2967)
  • Studies are needed to evaluate the impact that HPV vaccinations exert on oropharyngeal SCC
Clinical images

Images hosted on other servers:

Involving soft palate and tonsillar fossa

Gross description
  • May be exophytic (verrucous or papillary), endophytic, ulcerated
Microscopic (histologic) description
  • Usually moderate to poorly differentiated
  • HPV associated cancers tend to be poorly differentiated SCC in a basaloid background
Microscopic (histologic) images

Images hosted on other servers:

Fig 3-9: H&E, p16

Positive stains
  • CK5 / 6, p63
  • p16 positivity is highly predictive of lymph node metastasis in HPV associated cases
Negative stains
Differential diagnosis