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Surg Oncol Clin N Am. Author manuscript; available in PMC 2016 September 10.
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Published in final edited form as:

Surg Oncol Clin N Am. 2015 July ; 24(3): 491–508. doi:10.1016/j.soc.2015.03.006.

CANCER OF THE ORAL CAVITY

Pablo H. Montero, MD* and Snehal G. Patel, MD*
*
Head and Neck Surgery Service, Department of Surgery, Memorial Sloan-Kettering
Cancer Center

Keywords
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oral cavity cancer; oral cancer; squamous cell carcinoma; head and neck cancer

INTRODUCTION
1
Cancer of the oral cavity is one of the most common malignancies, especially in
2
developing countries, but also in the developed world . Squamous cell carcinoma (SCC) is
3
the most common histology and the main etiological factors are tobacco and alcohol use .
Although early diagnosis is relatively easy, presentation with advanced disease is not
uncommon. The standard of care is primary surgical resection with or without postoperative
adjuvant therapy. Improvements in surgical techniques combined with the routine use of
postoperative radiation or chemoradiation therapy have resulted in improved survival
4
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statistics over the past decade . Successful treatment of patients with oral cancer is
predicated on multidisciplinary treatment strategies to maximize oncologic control and
minimize impact of therapy on form and function.

ANATOMY OF THE ORAL CAVITY

The oral cavity extends from the vermilion border of the lips to the circumvallate papillae of
the tongue inferiorly and the junction of the hard and soft palate superiorly. The oral cavity
is divided into several anatomical subsites: lip, oral tongue, floor of mouth, buccal mucosa,
upper and lower gum, retromolar trigone and hard palate (Figure 1). Despite their
proximity, these subsites have distinct anatomical characteristics that need to be taken into
account in planning oncologic therapy.
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EPIDEMIOLOGY AND ETIOLOGY

Worldwide, 405,000 new cases of oral cancer are anticipated each year, and the countries
5
with the highest rates are Sri Lanka, India, Pakistan, Bangladesh, Hungary and France

Corresponding Author: Dr. Snehal G. Patel, Head and Neck Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New
York, NY 10065. Telephone: 212-639-3412, patels1@mskcc.org.
The Authors have nothing to disclose.
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 Montero and Patel Page 2

(Figure 2). In the European Union there are an estimated 66,650 new cases each year. The
American Cancer Society estimates that there will be 42,440 new cancers of the oral cavity
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6
and pharynx in the U.S. causing 8,390 deaths in 2014 . Tobacco smoking and alcohol are
3, 7
the main etiological factors in SCC of the oral cavity (SCCOC) . Other habits such as
betel nut and tobacco chewing have been implicated in the Asian population.

Tobacco contains many carcinogenic molecules, especially polycyclic hydrocarbons and

nitrosamines. A directly proportional effect exists between the pack years of tobacco used
8
and the risk of SCCOC . This risk can be reduced after tobacco cessation, but it does not
910
fully abate (30% in the first 9 years and 50% for those over 9 years) . A decreased
incidence of oral cavity cancer has been reported in the last 15 years, widely attributed to
11
a reduction in tobacco use .
Alcohol and tobacco seem to have a synergistic effect in the etiology of oral and
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3, 12, 13
oropharyngeal SCC . However, alcohol is linked to an increased risk of cancer even in
14 15 16
non-smokers . Other factors such as poor oral hygiene , wood dust exposure , dietary
17 18, 19
deficiencies , red meat and salted meat consumption have been reported as etiologic
factors. The herpes simplex virus (HSV) has been suspected but has not been implicated in
20
the etiology of SCCOC . Despite the emerging evidence supporting the role of the human
papilloma virus (HPV) in the etiology of oropharyngeal cancer, it has not been conclusively
21
linked to SCCOC . Host factors such as immune system alterations in transplant
22, 23 24
patients and HIV-infected patients with AIDS , and genetic conditions like xeroderma
pigmentosum, Fanconi anemia and ataxia telangiectasia are associated with an increased
25–28
incidence of head and neck cancer .
th
Oral cancer is more common in men and usually occurs after the 5 decade of life. About
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1.5% will have another synchronous primary in the oral cavity or the aero-digestive tract
29
(larynx, esophagus or lung) . Metachronous tumors develop in 10% to 40% in the first
30, 31
decade after treatment of the index primary and therefore regular post-therapy
surveillance and lifestyle alteration are important strategies for secondary prevention.

PATHOLOGY
Squamous cell carcinomas (SCC) constitute more than 90% of all oral cancer. Other
malignant tumors can arise from the epithelium, connective tissue, minor salivary
glands, lymphoid tissue, and melanocytes or metastasis from a distant tumor.

32
A variety of premalignant lesions have been associated with development of SCC . The
more common premalignant lesions including leukoplakia, erythroplakia, oral lichen planus,
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33
and oral submucous fibrosis have varying potential for malignant transformation . The
WHO (2005) classifies premalignant lesions according to degree of dysplasia into mild,
moderate, severe, and carcinoma in situ.

Leukoplakia is a clinical term defined as a “white patch or plaque that cannot be characterized
34
clinically or pathologically as any other disease” . This lesion is usually associated with
smoking and alcohol use. The prevalence of leukoplakia worldwide is about 2%. Dysplastic
changes are seen in only 2–5% of patients. The annual rate of malignant

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transformation for leukoplakia is 1%. Risk factors for malignant transformation include
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presence of dysplasia, female gender, long duration of leukoplakia, location on the tongue or
floor of mouth, leukoplakia in non-smokers, size greater than 2cm, and non-homogeneous
type. In addition to lifestyle alteration to avoid tobacco and alcohol use, excision constitutes
the only definitive modality for accurate diagnosis and treatment.

Erythroplakia is a “bright red velvety patch that cannot be characterized clinically or

34
pathologically as being caused by any other condition” . Surgical excision is
recommended as these lesions have higher malignant potential than leukoplakia and are
commonly associated with dysplasia and carcinoma in situ.

Non-squamous cell carcinomas of the oral cavity are uncommon. Minor salivary gland
carcinomas represent less than 5% of the oral cavity cancers. They frequently arise on the
35
hard palate (60%), lips (25%) and buccal mucosa (15%) . Mucoepidermoid carcinoma is
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the most common type (54%), followed by low-grade adenocarcinoma (17%), and
49,50
adenoid cystic carcinoma (15%) .
Mucosal melanomas are rare but usually present as locally aggressive tumors, mainly of
the hard palate and gingiva. Bony tumors including osteosarcoma of the mandible or
maxilla and odontogenic tumors such as ameloblastoma can present within the oral cavity
and may be mistaken for a mucosal lesion if there is surface ulceration.

CLINICAL PRESENTATION AND EVALUATION

Despite easy self-examination and physical examination, patients often present with
advanced stage disease. A comprehensive head and neck exam is mandatory in patients with
suspected oral cavity cancer. Visual inspection and palpation allow an accurate impression
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of the extent of the disease, the third dimension of tumor, the presence of bone invasion, or
skin breakdown. Appropriate documentation with drawings and photographic records of the
tumor are useful in staging, decision-making and further follow up.

The clinical TNM stage should be recorded at first encounter and modified as evaluation
progresses. The initial workup consists of diagnosis by biopsy. Accessible lesions may be
adequately biopsied in the clinic using punch forceps, core needle or fine-needle aspiration.
Some patients will require examination under general anesthesia (EUA) in order to access
posteriorly located lesions, or to complete a physical exam limited by pain and trismus.
Radiographic imaging is crucial for evaluation of the relation of the tumor to adjacent bone and
for assessing regional lymph nodes. CT scan is the study of choice for evaluation of bone and
neck nodes, especially early cortical involvement and extracapsular nodal spread. MRI provides
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complementary information about soft tissue extent and perineural invasion and is also helpful
for evaluating the extent of medullary bone involvement because adult marrow is normally
replaced by fat. Most patients with oral cancer are not at risk for distant metastases and
therefore the role of PET scan in initial assessment is debatable. However, a preoperative PET
scan may be useful as a baseline if adjuvant treatment is anticipated and a PET scan will be used
for radiation therapy planning (though this is undertaken differently from a “diagnostic” PET
scan). Patients with locally advanced tumors require appropriate

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multidisciplinary consultations with the reconstructive surgeon, medical specialists for

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presurgical optimization, dental professionals, speech and swallowing pathologists,

and behavioral therapists for smoking cessation and other lifestyle alterations.

The TNM system is the most widely accepted prognostic system due to its relatively
simple design and user-friendliness. The clinical staging of the oral cavity tumors consists
of primary tumor characteristics, the neck, and assessment for distant metastases (Table 1).
36
This information allows TNM stage grouping for the tumor (Table 2) . The basic
elements in staging of the primary site are the tumor size and invasion of deep structures.
Advanced disease is defined by invasion of structures such as medullary bone, deep muscle
of the tongue, maxillary sinus, and skin for T4a disease, or masticator space, pterygoid
plates, or skull base and/or encasement of the internal carotid artery for T4b disease.
Lymphatic spread into the neck generally occurs in a step-wise, orderly and predictable
fashion. The lymph node echelons of the neck are described using the terminology
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37
standardized by the American Head and Neck Society Guidelines (Figure 3).
Knowledge of the patterns of nodal metastasis has practical implications in the design of
neck dissection for patients with oral cancer. The patient with a clinically negative neck is at
38
highest risk of metastasis to levels I–III . Skip metastases to level IV do occur, especially
in cancer of the anterior tongue. Metastases to level V are extremely rare (1%) even in
patients with clinically positive neck. Oral tongue tumors have the greatest propensity of all
oral cancers for metastasis to the neck, and tumor thickness (Figure 4) is a major predictor
39
of risk of nodal metastasis .

TREATMENT
Surgical resection is the treatment of choice for SCCOC. Surgical resection allows accurate
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pathologic staging, with information about the status of margins, tumor spread and
histopathologic characteristics which can then be used to inform subsequent management
based upon assessment of risk versus benefit. Adjuvant radiotherapy ± chemotherapy is
used for specific indications in locoregionally advanced tumors. A multidisciplinary team is
absolutely essential to ensure a favorable outcome. Multiple factors are taken into account in
selecting treatment for an individual patient. The risk of treatment-related complications
should be assessed based on physiological age, comorbid conditions (e.g. cardiopulmonary
status), lifestyle (smoking or alcohol), surgical resectability, and patient expectations.

Surgical Management
A detailed description of surgical technique for management of oral cavity cancers is
beyond the scope of this publication and the reader is referred to specialized texts for this
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40
information . Broad principles of surgical management will be discussed and these include
access to the oral cavity, management of the mandible, management of neck nodes, and
reconstruction of oral cavity surgical defects.

Surgical access—The transoral approach is usually used for premalignant lesions and
small, superficial tumors of the anterior floor of mouth, alveolus and tongue. A more
invasive approach becomes necessary for posteriorly located tumors or if there are

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limitations due to trismus or inadequate surgical exposure (Figure 5). The lip-splitting
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paramedian mandibulotomy approach is used for larger posteriorly located tumors of

the tongue. The upper cheek flap and midfacial degloving approaches are useful for
gaining access to the maxilla.

Management of the mandible—Mandibular invasion can occur early in tumors of the

floor of the mouth, the ventral surface of the tongue and the gingivobuccal sulcus. The
41–43
mechanism of invasion of these tumors into the mandible has been well studied .
Tumors invade the mandible through the dental sockets in the dentate mandible, and
through the dental pores of the alveolar process in the edentulous mandible.

Early cortical invasion of the mandible is difficult to assess with plain radiography, or
orthopantomograms but CT scans are more sensitive. On a practical basis, tumors that are
in close juxtaposition to the mandibular cortex will require consideration for marginal
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mandibulectomy in order to achieve an adequate margin of resection irrespective of

radiographically demonstrable early cortical invasion. The role of marginal resection might
be limited in patients with reduced vertical height of the body of the mandible due to the
higher risk of early involvement of the body of mandible and the risk of pathologic fracture
if a marginal resection is performed. Adequate tumor clearance in edentulous patients may
therefore necessitate a segmental mandibulectomy. The indications for segmental resection
are listed in Table 3.

Management of the neck—Sixty percent of patients with early stage oral cancer will present
with a clinically negative neck (cN0). Approximately 20–30% will have microscopically evident
nodal metastasis on histologic examination after elective neck dissection (END). The risk of
44, 45
nodal metastasis is related to several factors (Table 4) . Cervical lymph node metastasis is
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the single most important prognostic factor in oral cancer: survival chances are reduced by 50%
46, 47
when compared to those with similar primary tumors without neck metastases . SCC of the
oral tongue and the floor of the mouth are more likely to metastasize to the neck, and these
patients should be offered END, even for early stage tumors, if they are thicker than about
48
4mm . The hard palate and the upper gum have a relatively lower rate of occult nodal
49
metastasis and END may not be indicated .

Sentinel node biopsy is an alternative to END for staging the cN0 neck in early stage (T1–2)
50
SCCOC. The technique was first reported in 2001 by Shoaib et al and has been analyzed
in several single institutional studies as well as two prospective multicenter trials, one in
51, 52 53
Europe and the other in the US . The procedure is technically challenging and
successful identification of sentinel nodes and detecting occult metastasis depends on
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expertise and experience. Therefore, it should be undertaken only in centers with the
54
necessary proficiency and the appropriate volume of cases .
In patients with clinically or radiographically involved neck nodes, a therapeutic comprehensive
neck dissection is indicated (Table 5). It involves dissection of levels I to V. The need to
sacrifice other structures such as the spinal accessory nerve, sternocleidomastoid muscle, or
internal jugular vein depends on the location of the metastasis and its characteristics. The most
common type of comprehensive neck dissection

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is the modified radical neck dissection, MRND Type 1. Radical neck dissection is
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rarely performed unless there is direct infiltration of the relevant structures by gross
extranodal extension of disease (Table 5).

In a patient with a clinically negative neck, the risk of occult metastasis is mainly to levels
I through III. Potential compromise of levels IV and V is very rare. For these reasons, a
supraomohyoid neck dissection (SOHND)(Table 5) is usually adequate to stage the cN0
neck. In patients with primary oral tongue SCCOC dissection of level IV may be indicated
due to the possibility of skip metastasis. For patient with positive nodes on END, neck
55
recurrence is observed in 10–24% . Appropriately selected patients benefit from
56, 57
postoperative radiation therapy . For cN0 patients who are proven pathologically N 0,
58
failure rates of less than 10% have been reported .

Reconstructive surgery—Restoration of form and function after ablative cancer surgery is

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the ultimate goal of treatment and is achieved by choosing the appropriate reconstructive
procedure. Surgical defects after resection of early stage tumors can usually be reconstructed
with primary closure or the use of skin graft or skin substitutes. Reconstruction of larger and
more complex defects that result from resection of advanced tumors requires participation from
59,
an expert reconstructive surgeon. Microvascular free tissue transfer is the technique of choice
60
. For example, in patients with soft tissue defects of the oral tongue, floor of mouth and
retromolar trigone, the free radial forearm flap results in excellent functional results (Figure 6).
In addition to soft tissue cover, free flaps are also a reliable source for bone reconstruction. The
fibula free flap is currently the workhorse in reconstruction of defects following segmental
mandibulectomy (Figure 6). Other composite microvascular flaps include the radial forearm
osteocutaneous flap, iliac crest and scapula free flaps. Several studies have demonstrated the
61
reliability and low morbidity of microvascular free flap reconstruction techniques . The ability
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reliably to reconstruct large surgical defects has contributed to improved oncologic outcomes in
62
patients with locally advanced cancers by enabling more complete resections . Pedicled
myocutaneous flaps such as the pectoralis major, latissimus dorsi or trapezius flaps are reliable
alternatives if surgical expertise is not available or if the patient is not a good candidate for
microvascular reconstruction.

Adjuvant treatment
Adjuvant postoperative treatment is indicated in patients with high risk of locoregional
recurrence. This includes patients with large primary tumors (pT3 or pT4), bulky nodal
disease (pN2 or pN3), metastases to nodal levels IV or V, positive surgical margins,
lymphovascular invasion, perineural invasion, and extracapsular spread. External beam
radiation therapy has been the traditional modality for postoperative adjuvant treatment
63, 64
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and doses of 66–70 Gy result in good locoregional control . Two clinical trials have
shown that administration of cisplatin chemotherapy concurrently with postoperative
radiotherapy improves locoregional control and survival (versus radiotherapy alone) in
head and neck cancer patients with extracapsular spread and /or positive surgical
65, 66
margins . However, concurrent chemoradiation can result in significant morbidity
and is best used at centers where appropriate expertise and infrastructure is available.

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OUTCOMES OF TREATMENT
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The results of treatment of SCCOC in recently published major series are shown in Table 6.
The overall 5-year survival in a recently analyzed cohort of patients at Memorial Sloan-
Kettering Cancer Center is 63%. This represents a significant improvement compared to
historical cohorts (Figure 7) and may be related to wider use of microvascular free flaps
with enhanced ability to resect large tumors and reconstruct large and complex defects,
more aggressive regional therapy including increasing use of elective selective neck
dissections, and the use of postoperative adjuvant therapy.

Approximately a third of patients treated for SCCOC relapse, and locoregional recurrence is
the most common pattern of failure. The clinical stage at presentation is an important
predictor of survival (Figure 8) but the most powerful predictor of outcome is the presence
of metastatic lymph nodes (Figure 9). Other clinical signs of locally advanced disease and
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poor prognosis include trismus, which indicates invasion of the pterygoid, temporalis or
masseter muscle; reduced tongue mobility, which indicates invasion of the extrinsic
musculature of the tongue or the hypoglossal nerve; and skin invasion with dermal
lymphatic infiltration. Significant histopathologic predictors of outcome include depth of
invasion of the primary tumor, positive margins of surgical resection, perineural invasion
and major extracapsular nodal extension.

Follow up
Oral cancer patients have a high risk of locoregional recurrence and developing subsequent
67
new primary cancers, but the risk of distant recurrence is low . The possibility of a second
head and neck primary is about 4–7% a year and comprehensive clinical examination and a
68
high suspicion are the cornerstones of early diagnosis . Control of lifestyle-related risk
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factors, such as tobacco and alcohol consumption, is a priority in these patients because of
69
the higher risk of treatment failure and second primaries . Unfortunately, there is no
effective chemoprevention and close follow up remains the most important tool in secondary
70
prevention . Baseline imaging studies are often obtained about 3–6 months following
completion of treatment and then as needed based on clinical suspicion. Chest imaging is not
routinely needed but may be beneficial in patients with a significant smoking history. Other
ancillary measures include speech and swallowing rehabilitation as indicated, monitoring of
thyroid stimulating hormone levels if the neck been treated with radiation therapy, and
regular dental evaluation.

CONCLUSION
Treatment results for patients with oral cancer have improved considerably over the last
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several decades due to improvements in reconstruction and adjuvant treatment. Further

improvements in survival have been hampered by attrition from second and subsequent
primary tumors in long-term survivors. Primary and secondary prevention of oral cancer
requires better education about lifestyle related risk factors, and improved awareness
and tools for early diagnosis.

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Key Points
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• Cancer of the oral cavity is a common malignancy in the United

States and around the world.

• The standard of care is primary surgical resection with or

without postoperative adjuvant therapy.

• Multidisciplinary treatment is crucial to improve the oncologic

and functional results in oral cancer patients

• Primary and secondary prevention of oral cancer requires education

about lifestyle-related risk factors, and improved awareness and
tools for early diagnosis.
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Figure 1.
Anatomic sites of the oral cavity
From Shah JP, Patel SG, Singh B, et al. Jatin Shah's head and neck surgery and oncology.
4th ed. Philadelphia, PA: Elsevier/Mosby; 2012, 232–244 with permisison.
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Figure 2.
Incidence of oral cavity cancer among both sexes expressed by level of Age-
standardized rate (ASR) in countries of the world (From GLOBOCAN 2012
International Agency for Research on Cancer (http://globocan.iarc.fr/Pages/Map.aspx.))
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Figure 3.
Cervical lymph node level classification
From Shah JP, Patel SG, Singh B, et al. Jatin Shah's head and neck surgery and oncology.
4th ed. Philadelphia, PA: Elsevier/Mosby; 2012, 232–244, with permisison.
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Figure 4.
Incidence of lymph node metastasis and survival stratified by the thickness of the primary
tumor. (From Shah JP, Patel SG, Singh B, et al. Jatin Shah's head and neck surgery and
oncology. 4th ed. Philadelphia, PA: Elsevier/Mosby; 2012, 232–244, with permisison.)
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Figure 5.
Various surgical approaches. A, Peroral. B, Mandibulotomy. C, Lower cheek flap. D,
Visor flap. E, Upper cheek flap. (From Shah JP, Patel SG, Singh B, et al. Jatin Shah's head
and neck surgery and oncology. 4th ed. Philadelphia, PA: Elsevier/Mosby; 2012, 232–244,
with permisison.)
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Figure 6.
Fibular (left) and radial forearm (right) free flaps are two of the most common flaps used in
oral cavity reconstruction after major resections.
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Figure 7.
Outcomes of treatment of SCCOC in three cohorts treated during different time periods
at Memorial Sloan-Kettering Cancer Center (1960–2005). Courtesy of Memorial Sloan-
Kettering database, New York, NY.
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Figure 8.
Clinical stage at presentation is an important predictor of outcome. Courtesy of Memorial
Sloan-Kettering database, New York, NY.
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Figure 9.
Impact of clinically palpable lymph node metastasis on disease-specific survival in SCCOC.
Courtesy of Memorial Sloan-Kettering database, New York, NY.
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Table 1

TNM classification of carcinomas of the oral cavity

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T — Primary tumor
TX Primary tumor cannot be assessed
T0 No evidence of primary tumor
Tis Carcinoma in situ
T1 Tumor 2 cm or less in greatest dimension
T2 Tumor more than 2 cm but not more than 4 cm in greatest dimension
T3 Tumor more than 4 cm in greatest dimension
T4a (lip) Tumor invades through cortical bone, inferior alveolar nerve, floor of mouth, or skin (chin or nose)
T4a (oral cavity) Tumor invades through cortical bone, into deep/extrinsic muscle of tongue (genioglossus, hyoglossus, palatoglossus,
and styloglossus), maxillary sinus, or skin of face
T4b (lip and oral cavity) Tumor invades masticator space, pterygoid plates, or skull base; or encases internal carotid artery
Note: Superficial erosion alone of bone/tooth socket by gingival primary is not sufficient to classify a as T4.
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N - Regional Lymph Nodes

NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 Metastasis in a single ipsilateral lymph node, 3 cm or less in greatest dimension
N2 Metastasis as specified in N2a, 2b, 2c below
N2a Metastasis in a single ipsilateral lymph node, more than 3 cm but not more than 6 cm in greatest dimension
N2b Metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension
N2c Metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension
N3 Metastasis in a lymph node more than 6 cm in greatest dimension
Note: Midline nodes are considered ipsilateral nodes.
M – Distant metastasis
MX Distant metastasis cannot be assessed
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M0 No distant metastasis
M1 Distant metastasis

From, Edge SB, Byrd DR, Compton CC, eds. AJCC Cancer Staging Manual. 7th ed. New York, NY.: Springer, 2010; 33, with permission.
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Table 2

Oral cancer staging

Author

Stage T N M
0 Tis N0 M0
Manus
cript

T1 N1 M0

I T1 N0 M0
II T2 N0 M0
III T3 N0 M0

T2 N1 M0
T3 N1 M0
IVA T4a N0 M0
T4a N1 M0
Autho

T1 N2 M0
T3 N2 M0
r

T2 N2 M0
Manuscrip

T4a N2 M0
t

IVB Any T N3 M0
T4b Any N M0
IVC Any T Any N M1

From, Edge SB, Byrd DR, Compton CC, eds. AJCC Cancer Staging Manual. 7th ed. New York, NY.: Springer, 2010; 33, with permission.
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Table 3

Indications for Segmental mandibulectomy

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• Gross invasion of the of the mandible

• Tumor fixation to the majority of the vertical height of the occlusal surface of the mandible in hypoplastic
edentulous mandible with significant loss of vertical height precluding safe performance of rim resection
• Tumor fixed to the mandible following prior radiotherapy to the mandible
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Table 4

Risk factors of nodal metastasis in oral cancer

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• Tumor Size
• Histologic Grade
• Depth of Invasion
• Perineural Invasion
• Vascular Invasion
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Table 5

Types of Neck Dissections

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Lymph Nodes Excised Other Structures Excised Structures Preserved

Radical Neck Dissection Levels I–V Sternocleidomast oid Muscle, Internal
(RND) Jugular Vein, Spinal Accessory Nerve,
Submandibular Gland
Modified Radical Neck Levels I–V Sternocleidomast oid Muscle, Internal Spinal Accessory Nerve
Dissection (MRND) Type I Jugular Vein, Submandibular Gland
Modified Radical Neck Levels I–V Internal Jugular Vein, Submandibular Sternocleidomoid Muscle, Spinal
Dissection (MRND) Type II Gland Accessory Nerve
Modified Radical Neck Levels I–V Submandibular Gland Sternocleidomast oid Muscle,
Dissection (MRND) Type III Internal Jugular Vein, Spinal
Accessory Nerve
Supraomohyoid Neck Levels I–III Submandibular Gland Sternocleidomast oid Muscle,
Dissection (SOHND) Internal Jugular Vein, Spinal
Accessory Nerve
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Table 6

Outcomes in patients treated for squamous carcinoma of the oral cavity in major series around the world.

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Series Country Year Total no. of Patients 5-years OS all patients 5-years DSS all patients Stage I Stage II Stage III Stage IV
72
Loree et al USA 1997 398 57.0% - - - - -
73
Chen et al Taiwan 1999 7032 36.1% - 72.0% 38.9% 26.7% 11.8%
74
Funk et al
Surg Oncol

USA 2000 30,803 43.5% - - - - -

75
Carvalho et al Brazil 2002 3642 43.0% - 74.0% 33.0%
76
Yeole et al78
India 2000 15051 45.9% - 68.9% 26.6% 9.5%
Germany 2012 15792 54.6% - - - - -
Cl
in

Listl et al
N

77
Rogers et al UK 2008 541 56.0% 74.0% - - - -
.Am

MSKCC USA 2014 1816 62.5% - 78.5% 68.4% 64.5% 34.5%

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