Oral Cancer

Oral cancer accounts for 4% of all cancer deaths or approximately 8,000 people in the United States each year. This is twice as many cancer related deaths as cervical cancer and more than melanoma, Hodgkin’s lymphoma and leukemia, brain, stomach, thyroid, ovarian, kidney, pancreas or esophageal cancer. Oral cancer is the 8th most common cancer in men and the 12th most common in women. There are 30,000 new cases per year in the USA.

Of all the types of cancer in the oral cavity 90% of them are a type called squamous cell carcinoma. Squamous cell carcinoma is a dangerous cancer and its early detection is the difference between surviving it or not. One risk factor associated with squamous cell carcinoma is tobacco use. Especially important is the total number of years the tobacco was used. Other factors are age over 50 years and tobacco with concurrent alcohol use.

Squamous cell carcinoma can be detected with self exam of the oral cavity by looking for abnormalities of the lining of the oral cavity. An exam by your dentist at regular intervals is also important because dental professionals are experienced in oral anatomy. The earliest signs of squamous cell carcinoma are tiny white patches, reddish areas and ulcers on the mucosa (wet skin of the mouth). When squamous cell carcinoma is detected early it is 80% curable but when it is detected late it is only 20% curable. That is why even small lesions should be tested.

Testing usually consists of a biopsy in which a small amount of tissue is taken. Sometimes a brush biopsy (Oral CDX) can be done.

Scalpel biopsy (Scalpel biopsy) is the gold-standard for pathologic testing however because it yields the most information. It can be done under local anesthesia or an anesthesia of your choice. Usually a small incision is made, a piece of tissue is taken, and then the site is sutured with resorbable sutures. The specimen is sent to a pathologist who is specially trained in oral diseases. In approximately ten days the results are returned to the office and our doctors personally reviews them with you and discusses any needed follow-up.

When a patient is found to have oral cancer their treatment is handled by a team approach. Initially the patient will have further testing to establish the extent of the disease including distant spread (metastasis). This establishes the tumor stage. Each type of cancer has its own staging protocol. For squamous cell carcinoma (SCCa) the stage is determined by the TNM system.

TNM System for Squamous Cell Carcinoma (SCCa)

T = Tumor size

Tx

Cannot assess 1° tumor

T0

No evidence of 1° tumor

Tis

Carcinoma in situ

T1

<2cm

T2

2-4cm

T3

>4cm

T4

Invades adjacent structures

N = Lymph Nodes

Nx

Cannot assess

N0

No lymph node metastasis

N1

Single ipsilateral <3cm node

N2

(3 subgroups below)

N2a

Single ipsilateral 3-6cm

N2b

Multiple ipsilateral <6cm

N2c

Bilateral or contralateral <6cm

N3

>6cm

M = Metastasis

Mx

cannot assess distant metastasis

M0

no distant metastasis

M1

distant metastasis

Stage Grouping

Once the T, N, and M categories have been assigned, this information is combined by a process called stage grouping to assign an overall stage of 0, I, II, III, or IV.

Stage 0

Tis, N0, M0

The cancer is “in situ”. It has not yet penetrated to a deeper layer of oral or oropharyngeal tissue and has not spread to lymph nodes or distant sites.

Stage I

T1, N0, M0

The tumor is 2 cm (about 3/4inch) or smaller and has not spread to lymph nodes or distant sites.

Stage II

T2, N0, M0

The tumor is larger than 2 cm, but smaller than 4 cm, and has not spread to lymph nodes or distant sites.

Stage III

T3, N0, M0 or T1, N1, M0 or T2, N1
M0 or T3, N1, M0

The tumor is larger than 4 cm; or it is any size and has spread to one lymph node, on the same side of the head or neck as primary tumor, which is smaller than 3 cm, and it hasn’t spread to distant sites.

Stage IVA

T4, N0, M0 or T4, N1, M0 or Any T, N2, M0

The tumor is of any size but invades adjacent structures and may or may not have spread to one lymph node, on the same side of the head or neck as primary tumor, which is smaller than 3 cm; or it is of any size and has spread to lymph nodes larger than 3 cm or to lymph nodes on both sides of the neck and it hasn’t spread to distant sites. The lymph nodes are smaller than 6 cm.

Stage IVB

Any T, N3, M0

The tumor is of any size and has spread to lymph nodes larger than 6 cm but it hasn’t spread to distant sites. 

Stage IVC

Any T, Any N, M1

The tumor is of any size, may or may not have spread to lymph nodes, but it has spread to distant sites.

Relative 5-year survival by stage

These survival numbers are more specific because they take into account the stage of the cancer, not just whether it has or hasn’t spread anywhere. (AJCC Cancer Staging Manual 6th Ed)

Lip Stage

5-year survival

Oral Cavity 
Stage

5-year survival

Oropharynx 
Stage

5-year survival

Stage I

83%

Stage I

83%

Stage I

83%

Stage II

73%

Stage II

73%

Stage II

73%

Stage III

62%

Stage III

62%

Stage III

62%

Stage IV

47%

Stage IV

47%

Stage IV

47%

Recurrent squamous cell carcinoma: This is not an actual stage in the TNM system. Recurrent disease means that the cancer has come back (recurred) after treatment has taken place. Recurrent oral cancer may return in the oral cavity (local recurrence) or in another part of the body (distant recurrence).

A radiologist oncologist (cancer specialist) will be consulted and depending on the type and extent of surgery a “head and neck” surgeon may be involved.

Each type of cancer responds differently to radiation therapy and chemotherapy. Chemotherapy has many different regimens. Squamous cell carcinoma which accounts for 90% of oral and pharyngeal cancers responds best to radiation. Treatment for squamous cell carcinoma usually consists of radiation therapy and surgery.

Radiation:

In addition to surgery, radiation therapy and sometimes chemotherapy is used to treat tumors of the head and neck. For squamous cell carcinoma radiation is often used as an adjunct to surgery. Preparations must be made prior to radiation therapy. Radiation to the head and neck region can cause permanent xerostomia (dry mouth) due to its effect on the salivary glands. It also causes decreased blood flow through the soft tissues and bone. These two effects are important because pre and post radiation care is shaped by it.

Pre-radiation care involves a dentist or dental specialist examining the health of all the teeth. Any questionable teeth that are not essential should be considered for extraction six-weeks before radiation therapy. In the case of cancer, aggressive removal of teeth is the conservative route. Post-radiation care for the remaining teeth includes at home fluoride treatments using custom trays, increased home care and quarterly instead of biannual dental visits.

Oral Cancer Pictures and Case Studies

Oral Cancer Case Study Photo

Caries susceptibility is greatly increased due to the loss of the saliva’s protecting factors. This puts the patient at increased risk for tooth loss due to deep caries.

Radiation therapy diminishes the blood flow in the jaws and makes future extractions problematic. A condition known as osteoradionecrosis can occur in the jaw bone around infected teeth or after simply extracting a tooth from an irradiated jaw (jaw that has had radiation). This condition is similar to osteomyelitis and results in death of, or infection of, bone tissue itself.

Osteoradionecrosis is difficult to treat and may require surgical debridement, hyperbaric oxygen therapy and long term IV antibiotics. For these reasons early removal of questionable teeth and excellent care for the remaining teeth is imperative.

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