• Oropharyngeal Cancer (Throat)
  • Symptoms & Diagnosis
  • Staging
  • Treatment
  • Recurrent Tumors

Oropharyngeal Cancer(Throat)

Anatomy

The pharynx is generally the area we consider as the throat. It is made up of several compartments; nasopharynx, oropharynx and hypopharynx. The oropharynx is the area of the throat above the voicebox extending to the top of the soft palate. The soft palate, the base of tongue, the tonsils, and the back & sidewalls of the pharynx are the different subsections of the oropharynx. These different subsections (excluding the tonsils) work together to coordinate the movement of food down the throat and along with the larynx direct it into the esophagus and down towards the stomach and avoid it by mistake going into the trachea and the lungs (Fig. 2a, 2b, 2c & 2d). As a consequence, tumors in this area can interfere with swallowing, breathing and if large enough our voice. By the same token, treatment of tumors in this area has to take into account these important functions, and every effort needs to be made to. preserve function.


Fig. 2a Oropharyngeal Cancer
 
Fig. 2b Oropharyngeal Cancer
     

Fig. 2c Oropharyngeal Cancer
 
Fig. 2d Oropharyngeal Cancer

Tonsils: The tonsils are the fleshy mounds on either side of the throat at the back of the mouth. These can be prone to infection, which is why they are often surgically removed.

Palate: There are two parts of the palate: the hard palate (the bony part on the roof of the mouth), and the soft palate (further back, at the top of the throat). The soft palate is the part that is considered to be a region of the oropharynx, while the hard palate is considered to be part of the oral cavity.

Base of Tongue: The base of the tongue is made up of different tissues than the front part, which is considered part of the oral cavity. Since the tissue types are different, the cancers that can arise in them are different as well.

Pharyngeal Wall: This is the lining of the area on the back and the side of the throat.

Symptoms & Diagnosis

Tumors in the oropharynx can cause a variety of symptoms. Symptoms usually include chronic sore throat, one sided ear pain, swallowing problems, chronic cough and/or blood tinged sputum. A person who has a tumor that is large enough to reach the voice box may have hoarseness as well. Any of these symptoms present for more than 2 to 3 weeks requires examination by a specialist.

Risk Factors

Men are more often affected by cancer of the larynx than women. Laryngeal cancer is closely associated with cigarette smoking. Exposure to the chemicals in tobacco as they pass by the structures in the mouth, throat, voice box, and lungs is thought to lead to development of cancer. Tobacco and alcohol use each have been found to increase the risk by many folds (as high 20-30 folds). However, tobacco and alcohol use together can increase the risk of cancer by 70 folds. There is also an association with HPV (human papilloma virus) infection.

Diagnosis

The diagnosis is made by looking at the throat directly or with a small fiberoptic camera (laryngoscope) performed in the office. This simple procedure takes less than 20 seconds and shows the larynx clearly so that size of the tumor can be assessed. When larger more extensive tumors are found we often perform a CT scan, MRI, or even a PET scan. (CT Scan Left Base of Tongue Mass)

To confirm the diagnosis a biopsy must be done of the mass. This also is a simple procedure taking only a few minutes. When the tumor is on the palate or the tonsil it may be biopsied in the office, however when the mass is lower in the throat biopsying involves using a camera and sampling a small piece of the tumor. In a majority of cases, our gag reflex prevents us from being able to have this done in the office. (PET Scan Left Base of Tongue Mass )

Staging

The TNM Staging is a universally used system based on size (T), lymph node involvement (N), and distant spread or metastasis (M)

Table 1
T Stage Primary Tumor
T1 Tumor less then 2cm in size
T2 Tumor between 2 to 4cm
T3 Tumor more than 4cm
T4a Tumor invades the larynx, deep extrinsic muscle of the tongue, medial pterygoid muscle, hard palate or mandible.
T4b Tumor invades lateral pterygoid muscle, lateral nasopharynx, skull base, or encases carotid artery.
N Stage Regional Lymph Nodes
N0 No Lymph Nodes
N1 Single Node Less than 3cm on the same side
N2a Single Node 3 to 6 cm on the same side
N2b Multiple Nodes Less than 6cm on the same side
N2c Nodes on Both or Other Side Less than 6cm
N3 Node Larger than 6cm
   
M Stage Distant Metastasis
M0 No Distant Metastasis
M1 Distant Metastasis Present
Table 2
Stage Group
Stage T N M
0 Tis N0 M0
I T1 N0 M0
II T2 N0 M0
III T3
T1,T2,T3
N0
N1
M0
M0
IVa T4a
T4a
T1,T2,T3 or T4a
N0
N1
N2
M0
M0
M0
IVb
Any T
T4b
N3
Any N
M0
M0
IVc Any T Any N M1

Treatment

The Tumors in the throat usually develop first as a small white plaque on the surface; this small white plaque is called Leukoplakia. These tumors gradually change their character and become more aggressive. In the early stages these tumors are called dysplasia, and in time it becomes moderate dysplasia and then severe dysplasia. These are still pre-cancerous stages. Once the tumor changes and becomes cancer, it is now very aggressive and can destroy the tissue around it, additionally it can it can spread to other parts of the body.

So during this early stage, the tumor is less aggressive and more easily treated, which is why seeing a doctor or specialist immediately soon after symptoms start is very crucial. When a biopsy confirms that the tumor is not cancerous but rather Dysplasia, the treatment involves removing the superficial surface layer only where the lesion (Dysplasia) is and nothing more. This procedure is called vocal cord stripping and it is not much more complicated then the biopsy itself.

T1 & T2 The smaller tumors of the pharynx do not involve the deeper structures; as such they can be readily treated with high cure rates.The treatment options include Transoral endoscopic laser surgery (surgery through the mouth rather than through a cut in the neck), radiation therapy (for smaller tumors) or chemo-radiotherapy for larger tumors. Our expert team of doctor’s assesses the patient to determine which treatment option is most appropriate for the patient in terms of cure and swallowing outcomes. Cure rates and swallowing for the two different treatment types can be very similar. Each patient though is individually evaluated to make sure they receive the best treatment possible. (T1 Base of Tongue Tumor)


T2 Base of Tongue Tumor
 
T2 After Transoral Laser Surgery

T3 & T4 These larger tumors obviously involve deeper structures of the oropharynx.(Fig. 9, 10) The treatment of choice is a combination of chemotherapy and radiation. This is an involved and rigorous treatment and requires the patient not only to work closely with his/her doctor’s (Head & Neck Surgeon, Oncologist, and Radiation Oncologist), but also have a strong bond with them. This is a difficult therapy and our doctors believe that this bond is of an utmost importance in helping to assure success. Additionally, patients are followed by nutritionist and swallow therapists to make sure they continue to do well.


T3 Base of Tongue Tumor
 
T4 Base of Tongue Tumor

 

Recurrent Tumors

When cancer recurs its best that it be diagnosed early, which is the reason all of our patients are followed closely, at least once every 3 months, if not more closely and with regular imaging studies such as CT, MRI, or PET scans. In a patient that has not been treated with radiation therapy before for their original tumor, then the option of radiation therapy exists. ( Generally, radiation therapy can be only used once on each area of the body) Most recurrences are, however, after previous radiation or a combination of chemo-radiation treatments. All patients whom have had a recurrence are considered for Transoral Endoscopic Laser Microsurgery. If this approach is not permissible due to the size and location of the tumor than an open surgical procedure is considered. We use a multiple-surgeon approach that makes it possible to both remove the cancer and reconstruct the area. The criterion to proceed with a transoral approach is, simply put, visibility and therefore accessibility to the entire tumor through the mouth. This is dictated by the experience of your surgeon and availability of the appropriate equipment. Our team of expert surgeons will consider each case individually to decide the appropriate course of action.

Cancers of the throat are generally treated with surgical removal, sometimes to be followed by radiation. Usually cessation of tobacco use is an important part of any treatment plan, and our office is happy to help you with this challenging step. The structures of the throat are important for speech and swallowing, and our physicians are very good at preserving these functions as much as possible. We use a multiple-surgeon approach that makes it possible to both remove the cancer and reconstruct the area. Often speech and swallow therapy is incorporated into the treatment plan after surgery, to help the patient maintain the ability to perform daily activities.