Review articleCarcinoma of the oral pharynx: an analysis of subsite treatment heterogeneity
Section snippets
Relevant anatomy
The superior and inferior boundaries of the oropharynx are marked by horizontal planes at the levels of the hard palate and vallecula or hyoid bone, respectively. The muscular pharyngeal wall between these two planes defines the posterior limits. The circumvallate papillae and palatoglossal muscle mark the anterior limits. Most of the lateral wall of the oropharynx is primarily composed of the tonsil and the tonsillar fossa. A small contribution comes from the lateral extensions of the
Histopathology
In general, the histopathologic entities seen in the oropharynx represent a derivation of tissue normally present there. Because the oropharynx is lined with stratified squamous epithelium, 85% to 90% of carcinomas seen are squamous cell in origin. The presence of minor salivary glands, neurovascular and fibromuscular structures, and lymphoid aggregates in the Waldeyer's ring opens the possibility to a wide variety of mesemchymally derived sarcomas and carcinomas. A discussion of the management
Assigning tumor to subsite of origin
Determining the subsite of origin in oropharyngeal carcinomas can be a daunting task and frequently comes down to an educated guess based on subjective and objective information. The reason for the great difficulty is twofold. The first factor relates to mucosal continuity between subsites, making it difficult to strictly demarcate one subsite from another. For example, the soft palate, which includes the uvula is continous with the anterior tonsillar pillar. Similarly, the lateral extension of
Posterior pharyngeal wall
Tumors that are isolated to the posterior pharyngeal wall are very uncommon. They tend to be asymptomatic unless they become bulky. They rarely extend laterally to other subsites of the oropharynx but rather infiltrate deeply into the retropharyngeal and prevertebral tissues. They are known for their early metastases to bilateral jugular and retropharyngeal nodes because of their posterior and relatively midline location. The biologic characteristics of these tumors are the same as those of
Soft palate
The soft palate functions to prevent air escape during phonation and nasal regurgitation during deglutition. Of all the subsites of the oropharynx, it may provide the least challenge to routine examination. Thus, despite the relatively asymptomatic presentation of carcinomas in this region, they are usually identified early and referred for definitive management.
SCC of the soft palate is a relatively uncommon malignancy and remains virtually asymptomatic because of its location, until a lesion
Tonsillar complex
Tonsillar carcinoma represents approximately 75% of all carcinomas presenting in the oropharynx. Among carcinomas of the aerodigestive tract, it ranks second only to laryngeal cancer. Unlike the soft palate, the more cryptic locations of the tonsillar complex places this region at high risk for being poorly visualized or overlooked by the casual examiner. This is one reason the source of many unknown primary tumors is ultimately found to originate in the tonsil. Furthermore, its relatively “out
Tongue base
Treatment selection for base of tongue carcinomas is institutionally driven. Some centers primarily use surgery with or without radiotherapy [21], [22], [23], [24], [25], [26], [27], [28]; others use primary radiotherapy and reserve surgery for salvage [29], [30], [31]. The role of brachytherapy remains controversial. Brachytherapy combined with external beam radiotherapy (EBRT) was initially believed to be a superior treatment option to EBRT alone for base of tongue lesions. It has since
Approach to management of the neck
Management of the regional lymphatic spread of disease is virtually the same for all subsites of the oropharynx. The risk of occult cervical metastases ranges from 15% to 30%; therefore, treatment of N0 neck lesions is justified for all T stages of disease. Most early-stage primary lesions are treated with definitive radiotherapy, which is also used to address clinically negative neck lesions. Elective neck dissections also can be used in this setting and produce equal control rates with the
Chemotherapy
In the past, the role of chemotherapy in the treatment of oropharyngeal carcinoma was generally considered experimental and used for palliation. Most patients being treated with chemotherapy were either enrolled in a study or were receiving treatment at a research-based institution.
There are now many promising cytotoxic agents currently under investigation. There exists no way to ascertain from the literature the true independent effects of chemotherapy on oropharyngeal carcinomas, however,
Summary
The data indicate that SCC of the various subsites of the oropharynx can be treated successfully with acceptable locoregional control and survival rates by using either surgery or primary radiotherapy for T1 or T2 primary lesions. Treatment success data for late-stage disease (T3 and T4) are less encouraging, regardless of which modality is used or which treatment center is administering treatment. This finding may suggest an intrinsic property of these lesions or the patient that may be going
References (37)
- et al.
Carcinoma of the soft palate treated with irradiation: analysis of results and complications
Radiat Oncol
(1987) Carcinoma of the tongue
Otolaryngol Clin North Am
(1979)- et al.
Time-dose relationships for local tumor control and complications following irradation of squamous cell carcinoma of the base of tongue
Int J Radiat Oncol Biol Phys
(1987) - et al.
A reevaluation of split-course technique for squamous cell carcinoma of the head and neck
Int J Radiat Oncol Biol Phys
(1980) - et al.
Treatment selection for carcinoma of the base of tongue
Am J Surg
(1990) - et al.
Primary radiation therapy in the treatment of squamous cell carcinoma of the soft palate
Cancer
(1989) - et al.
Squamous cell carcinoma of the soft palate, uvula, and anterior faucial pillar
Otolaryngol Head Neck Surg
(1988) - et al.
Carcinoma of the oropharynx: soft palate
J Otolaryngol
(1984) - et al.
Results of irradiation in squamous cell carcinoma of the soft palate and uvula
Radiother Oncol
(1988) - et al.
Primary radiation therapy in the treatment of squamous cell carcinoma of the soft palate
Cancer
(1989)
Carcioma of the soft palate
J Laryngol Otol
Squamous cell carcinoma of the soft palate, uvula, and anterior faucial pillar
Otolaryngol Head Neck Surg
Carcinoma of the soft palate and anterior tonsillar pillar
Laryngoscope
Carcinoma of the tonsillar region
Laryngoscope
Carcinoma of the tonsillar fossa: an update
Arch Otolaryngol Head Neck Surg
Definitive radiotherapy for squamous cell carcinoma of the tonsillar fossa
Int J Radiat Oncol Biol Phys
Cancer of the tonsil
J Otolaryngol
Carcinoma of the tonsillar regions: a comparison of radiation therapy with combined radiation and surgery
Otolaryngol Head Neck Surg
Cited by (20)
Pitfalls in the Staging of Cancer of the Oropharyngeal Squamous Cell Carcinoma
2013, Neuroimaging Clinics of North AmericaCitation Excerpt :The proportion of HNSCC arising in the OP increased from 18% in 1973 to 32% in 2005.8 Minor salivary tumors (adenomas/adenocarcinomas), lymphoid lesions (including lymphoma), undifferentiated malignancy, and sarcomas make up the balance of the tumors arising in the OP.9 While overall incidence of other HNSCCs has been declining since the 1980s, the incidence of OP SCC has been stable or increasing.
Oropharynx Cancer
2012, Current Problems in CancerCitation Excerpt :However, soft palate cancers tend to present at earlier stages because of the development of symptoms even with small lesions and facile visualization of this area. Nevertheless, these lesions tend to be more extensive than initially thought because of their tendency to be locally infiltrative with indistinct boundaries.228 Because the soft palate rests in the midline of the oropharynx with no clear anatomic barriers preventing soft tissue extension, these lesions often can extend to other subsites bilaterally.
Factors influencing the outcomes of primary surgery with postoperative radiotherapy for pN2 oropharyneal squamous cell carcinoma
2012, Oral OncologyCitation Excerpt :Second, although surgery alone provides a better chance of local control than does radiation alone in stage III/IV tonsillar complex disease, the rate of locoregional recurrence remains unacceptable, even when surgery achieves negative margins. Finally, a number of meta-analyses have demonstrated significantly lower rates of local recurrence when multimodal approaches are used, as compared to just surgery or radiation therapy alone.10,11 Radiotherapy or chemoradiotherapy is often advocated as the primary treatment modality for all stages of OPSCC, with surgery being reserved for recurrent or persistent locoregional disease.
Combined surgery and postoperative radiotherapy for oropharyngeal squamous cell carcinoma in Korea: analysis of 110 cases
2008, International Journal of Oral and Maxillofacial SurgeryCitation Excerpt :One factor contributing to this poor survival might be the difficulty in examining the base of the tongue, therefore carcinomas found there are likely to be more advanced when diagnosed. The soft palate is easy to examine so, despite the relatively asymptomatic presentation of carcinomas in this region, they are usually identified early and referred for definitive management17. This study also confirmed that 95% of base-of-the-tongue lesions were classified as advanced AJCC stage, but only 47% of soft palate lesions were advanced.
Biochemical analysis of saliva in head and neck cancer patients receiving definitive chemoradiotherapy
2023, Journal of Cancer Research and TherapeuticsOropharyngeal tumour surgery
2021, Operative Surgery for Head and Neck Tumors