Site:
Oropharynx (Base Of The Tongue, Tonsillar Fossa, Lateral Oropharyngeal Wall, And Faucial Arch)
Stage:
Stage I & II, T1 N0 M0, T2 N0 M0
Stage III & IV, T3, T4 N0, T3, T4 N1, & T3, T4N2, N3
  1. DIAGNOSTIC EVALUATION
  2. EXAMINATION UNDER ANESTHESIA AND BIOPSY
  3. TREATMENT
  4. RECONSTRUCTION
  5. ADJUVANT TREATMENT
  6. FOLLOW UP
  7. BIBLIOGRAPHY

I. DIAGNOSTIC EVALUATION:

Clinical Evaluation:
  • Complete history and physical examination

    Recording the presence and duration of symptoms such as pain, soreness of throat, otalgia, odynophagia, dysphagia, trismus, neck mass and voice changes such as hoarseness, "hot potato voice", and slurred speech. It should include history of risk factors such as the use of tobacco and alcohol, the occurrence and extent of weight loss and of all other medical conditions.
  • Complete examination of the head and neck.

    Includes examination of all the areas of the oral cavity, pharynx, and indirect laryngoscopy. If indirect laryngoscopy is not adequate, fiberoptic examination of the larynx and pharynx is necessary. Palpation of the floor of the mouth, tongue, base of the tongue and or tonsil to evaluate the "base" or depth of the tumor and its proximity to the mandible. The examination includes an assessment of the status of the mandible and the dentition, as well as an evaluation of the status of the airway. Palpation of the neck bilaterally, recording the location (Group or Level I - VI), size, mobility, and relationship of the node(s) to adjacent structures. The staging of the primary and of the cervical lymph nodes must be documented. 
  • Biopsy of primary

    The biopsy can be performed in the office with local anesthesia and a cup- biopsy forceps. If the patient has a severe gag reflex, biopsy may be necessary under general anesthesia, in the operating room. To do this, in patients with large tumors, a tracheostomy may be necessary. 

Fine needle aspiration biopsy of suspected metastatic disease may be performed in selected cases. (Open surgical biopsy of suspected metastatic disease is not indicated)

Imaging Studies:

  • Panoramic x-ray (Panorex) of the mandible and/or dental X-rays.

    When necessary to adequately assess the status of the patient's dentition or mandibular invasion. In anticipation of radiation therapy or the need for a mandibulotomy.

  • Chest radiographs, PA and lateral

    To rule out (1) A synchronous pulmonary tumor, (2) Acute or chronic pulmonary disease (3) Metastatic tumor. Abnormal findings on chest x-ray with suspicious lesions may need further imaging including a chest CT.

  • CT scan / MRI of the primary and neck

    To assess the extent of the primary, its relation to the mandible, and to evaluate if there is any mandibular involvement.

    In the absence of palpable adenopathy, they may be useful to assess the status of the cervical lymph nodes in patients that are obese or have a thick, muscular neck.

    To assess the presence of parapharyngeal adenopathy

    When a large node is palpable in the neck, may be useful to clarify its relationship to the carotid artery, the paraspinal muscles or the cervical spine.

Laboratory Tests:
  • Pre-anesthesia laboratory tests (according to institutional guidelines)
  • Baseline liver function tests (optional)
Consultations:
  • Radiation therapy consult

In anticipation of possible need for post-operative radiation therapy or to use radiation therapy as a definitive primary modality of treatment when appropriate.

  • Dental consultation 

To assess the status of the teeth and to make recommendations regarding the condition of the mandible prior to surgery, mandibulotomy or post-operative radiation therapy. The evaluating dentist should be versed in the effects of radiotherapy on dentition. This evaluation should be done with knowledge of the treatment portals planned for the radiotherapy.

Optional:
  • Radiation therapy consult

Either for free tissue transfer or for myocutaneous flap.

  • Dental consultation 

For pre-operative counseling regarding possible post-operative speech and swallowing rehabilitation.

  • Internal Medicine/ Cardiology/ Pulmonology/Anesthesiology

As needed to evaluate coexisting conditions that may preclude or increase the risk of general anesthesia

Top

II. EXAMINATION UNDER ANESTHESIA AND BIOPSY:

This is an important step in the evaluation of tumors of the oropharynx.

  • Palpation of the base of the tongue and direct evaluation of the extent of the disease, especially the lower extent of the disease in the pharyngeal wall and to rule out involvement of the hypopharynx. The adequacy of the airway should be judged at this time.   
  • Direct laryngoscopy, pharyngoscopy.   
  • Esophagoscopy (Optional, unless symptoms present) 
  • Bronchoscopy should be considered only if there are abnormal clinical or radiographic findings. 
  • It is appropriate to have an intraoperative consultation with the radiotherapist, especially if the patient is to be treated with radiation therapy as a primary modality or planned interstitial implantation for tumors of the base of the tongue is being considered. 
  • In patients with large tumors it may require tracheostomy under local anesthesia.

Top

III. TREATMENT:

The decisions regarding the treatment of cancer of the oropharynx must be individualized. Tonsillar cancers are more radiosensitive and general practice is to treat them by radiation therapy with surgery as salvage, unless the patient presents with very early tonsillar cancer. A bulky nodal disease from tonsillar cancer also responds extremely well to radiation therapy. On the other hand, tumors of the base of the tongue, if early, can be resected or treated with radiation.

In advanced cancers of the base of the tongue, generally surgery is preferred as the initial modality followed by radiation therapy; however, external radiation therapy along with brachytherapy may be a good choice. In general nodal metastases from base of tongue tumors do not respond as well to radiation and will usually require neck dissection for persistent clinical disease. 

Primary tumor:

Generally T1 or T2 primary tumor of the oropharynx can be treated equally well with surgery or radiation therapy. The choice of treatment will depend on the patient's preference, the patient's medical condition, the institutional practice and the complexity of the surgical exposure. Treatment of base of the tongue tumors may include brachytherapy. Adequate surgical approaches and exposure of early tumors of the oropharynx may be difficult requiring mandibulotomy, pharyngotomy or occasionally, if the tumor is adherent to the mandible, composite resection with segmental mandibulectomy. Generally T3 and T4 tumors are treated with surgery (if consistent with a reasonable functional outcome and perioperative risk) and, in most instances, postoperative radiation therapy. Otherwise they may be treated initially with radiation therapy. Predominantly exophytic, poorly differentiated or lymphoepithelioma type tumors may be treated initially with radiation therapy. 

External radiation therapy, along with interstitial implantation (brachytherapy) to the base of the tongue, may result in equally good local control and avoid morbidity related to resection of the tumors of the base of the tongue. However, neck dissection is usually necessary for persistent palpable disease.

Neck:

N0:Many base of tongue and lateral oropharyngeal wall tumors have a tendency to cross the midline. Consequently, the incidence of metastases to both sides of the neck is high in tumors of the oropharynx. Therefore, treatment should consist of elective bilateral neck dissection or neck irradiation. If treated with surgery, indications for postoperative irradiation are outlined below.

N1:Ipsilateral modified neck dissection where the spinal accessory nerve is preserved, or if the disease is at Level I, ipsilateral supraomohyoid neck dissection may be considered. 

N2 or N3:Ipsilateral radical neck dissection with sacrifice of sternomastoid muscle, internal jugular vein and spinal accessory nerve should be considered. If the tumor is away from the spinal accessory nerve, every effort should be made to preserve the spinal accessory nerve.    

Top

IV.RECONSTRUCTION:

Primary closure may be possible if the lateral pharyngeal wall or a small portion of the base of the tongue are resected. For larger defects a pectoralis muscle myocutaneous flap or a free flap may be considered.

The surgical treatment also includes:

  • Frozen section evaluation of margins as needed to ensure adequate resection.

  • Dental extraction if indicated.

  • Mandibulotomy for exposure and rigid fixation with wires or mini-plates.

  • Insertion of suction drains.

  • Tracheostomy.

  • Orientation of the primary and neck specimens to the pathologist, with appropriate identification of the groups/levels of lymph nodes removed).

Post-operative and Home Health care:

  • Hospitalization for 7 - 21 days.

  • Tube feedings. 

  • If the patient is unable to eat by the time of discharge, patient may require tube feedings at home. If the tumor is extensive and patient is likely to have considerable difficulty in swallowing, consideration may be given to inserting a percutaneous gastrostomy (PEG). 

  • Removal of the drains when the output is < 30 - 50 cc's per 24 hours.

  • Intensive oral irrigation and oral care.

  • Tracheostomy care and patient education for tracheostomy.

  • Removal of neck sutures in 7 - 10 days

  • If the patient has an adequate airway and can tolerate oral feedings, consider weaning from tracheostomy. If there is considerable edema and difficulty in swallowing, tracheostomy tube may be left in place through the post-operative radiation therapy course.

Top

V.ADJUVANT TREATMENT:
Role of chemotherapy in Stage III & IV:
  • Chemotherapy: The role of chemotherapy in the treatment of tumors of the oropharynx remains under active investigation. Chemotherapy should be used only under an approved experimental protocol. 
  • If patient has extensive tumor of the oropharynx which may necessitate total laryngectomy, an IRB approved larynx preservation protocol may be considered.

Post-operative radiation:

Indications:

Microscopically positive margins:

  • Presence of extensive perineural or intravascular invasion.   
  • Multiple histologically positive nodes.  
  • Positive nodes at multiple levels in the neck.  
  • Presence of extracapsular extension of tumor.

Timing:

  • Radiation is initiated within a reasonable period after healing has occurred.  
  • Total dose and fractionation:  
  • These are determined by the clinical and pathological findings. The usual range is 50 - 70 Gy in daily fractions of 1.8 to 2.0 Gy in 5 to 8 weeks. This may include a brachytherapy boost when indicated by pathological findings such as unsatisfactory margins.

Top

VI.FOLLOW UP:

Follow-up appointments are scheduled on an individual basis determined by the risk of recurrence, to survey for the development of second primary tumors, to deal with morbidity from treatment (i.e. speech and swallowing problems as well as wound care), to provide social and psychological support, and to deal with comorbidity not directly related to the cancer itself.

  • Periodic examinations by the head and neck surgeon may be necessary during radiation therapy in patients experiencing difficulty with nutritional intake, airway or pain control.

  • Periodic examinations by the radiation oncologist and a dentist in patients that received radiation therapy

  • After all treatment is completed a general formula which is modified according to the individual patient's characteristics is:

    1st year post treatment  : 1-3 months
    2nd year post treatment : 2-4 months
    3rd year post treatment : 3- 6 months
    4th and 5th years          : 4- 6 months
    After 5 years                : Every 12 months

  • Chest radiographs, yearly.

  • Liver enzymes, yearly.

  • Thyroid function tests should be monitored within the first year following completion of treatment if a thyroid lobectomy is performed (along with laryngectomy) or if the patient received radiation to the lower neck. These studies should be repeated according to clinical findings on follow-up examinations.

Top

VII.BIBLIOGRAPHY:

O'Brien C, Castle G, Stevens G, et al. Limitations of radiotherapy in definitive treatment of squamous carcinoma of the tonsillar fossa. Aust NZJ Surg, 62: 709-713, 1992.

Harrison LB, Zelefsky MJ, Sessions RB, et al. Base of tongue cancer treated with external beam irradiation plus brachytherapy: oncologic and functional outcome. Radiology 184: 267-270, 1992.

Wang C, Montgomery W and Efird J. Local control of oropharyngeal carcinoma by irradiation alone. Laryngoscope, 105: 529-533, 1995.

Weber R, Gidley P, Morrison W, et al. Treatment selection for carcinoma of the base of tongue. Am J Surg, 160: 415-419, 1990.

Million R, Parsons J and Mendenhall W. Selection of treatment for squamous cell carcinoma of the oropharynx. Head Neck Cancer, Proc. 3rd, Conf. 3:785-792, 1993.

Spiro RH, Gerold FP, Shah JP, Sessions RB, Strong EW. Mandibulotomy approach to oropharyngeal tumors. Am J Surg, 150, Oct. 1985.

Harrison L, Zelefsky M, Armstrong J, et al. Performance status after treatment for squamous cell cancer of the base of the tongue. Int J Rad Onc Biol, Phys, 30: 953-957, 1994.

Pfister D, Harrison L, Strong E, et al. Organ-function preservation in advanced oropharynx cancer: results with induction chemotherapy and radiation. J of Clin Onc, 13: 671-680, 1995.

Horiot JC, Le Fur R, N'Guyen T, et al. Hyper-fractionated compared with conventional radio-therapy in oropharyngeal carcinoma: An EORTC randomized trial. Eur J Cancer, 26: 779-80, 1990.

Merlano M, Vitale V, Rosso R, et al. Treatment of advanced squamous cell carcinoma of the head and neck with alternating chemotherapy and radiotherapy. N Engl J Med, 327: 1115-21, 1992.