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Chapter 19

Malignant Lesions of the Head and Neck

Joseph R. Spiegel

Robert T. Sataloff

David A. Zwillenberg

I Overview

Table 19 -1 shows the basic characteristics of head and neck cancer.

A Epidemiology

Primary malignant neoplasms of the head and neck, excluding skin cancer, account for 5% of new cancers each year in the United States.

The male:female ratio is 3:1 to 4:1, and most lesions occur in patients older than 40 years of age.

Approximately 80% of primary head and neck malignancies are squamous cell carcinomas. The remainder are thyroid cancers, salivary neoplasms, lymphoma, and other less common tumors.

The number of patients with a second primary malignancy at the time of initial presentation has been reported to be as high as 17%.

B Risk factors

Tobacco use (chewing or smoking), alcohol consumption, and exposure to radiation are etiologic factors in most squamous cell carcinomas of the head and neck.

Approximately 85% of patients with head or neck cancer smoke or formerly smoked cigarettes at the time of diagnosis.

C

Evaluation of the patient starts with a careful history and physical examination.

History. The patient should be questioned about:

Exposure to etiologic agents (e.g., tobacco, alcohol, sawdust, other toxins, and irradiation)

Associated symptoms , including hoarseness or sore throat of more than 3 weeks' duration, dysphagia, dyspnea, nonhealing ulcers, hemoptysis, and neck mass

Any history of head or neck malignancy

Nutritional status, family history, and psychosocial status

The patient's nutritional status is of prime concern when choosing therapy. Many patients are malnourished, either because of alcoholism or an obstructive tumor.

Treatment is sometimes delayed or limited because of the need for hyperalimentation. In most patients, this requirement can be met with nutritional supplements or tube feedings into the stomach, but parenteral nutrition is sometimes required.

The family history is critical in some head and neck tumors with inherited factors (i.e., medullary thyroid cancer)

Physical examination must include an inspection of all the skin and mucosal surfaces of the head and neck.

An intranasal examination and indirect mirror examination of the nasopharynx and hypopharynx are included.

Careful palpation of the oral cavity, base of the tongue, and oropharynx is mandatory.

Fiberoptic examination of the nose, pharynx, and larynx is indicated in all patients who are being evaluated for head and neck cancer.

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TABLE 19-1 Basic Characteristics of Head and Neck Cancer

D

Treatment is based on the site and pathology of the primary cancer and the extent of the local, regional, and distant disease (Fig. 19 -1).

Surgery is the indicated treatment for many patients with head and neck cancer. The time for treatment is short, and careful pathologic examination of the tissue removed is possible. In addition, the effects of radiation are avoided, and radiation can be saved for recurrent disease or other primary cancers. The choice of surgery can be influenced by many factors.

Malnourishment can increase the perioperative risk of morbidity and mortality.

The patient may have a coexistent systemic disease (e.g., diabetes, chronic obstructive pulmonary

disease, or coronary artery disease), which increases the surgical risk.

The necessary procedures can be disfiguring and can leave the patient with severe functional deficits.

Resection of the larynx, for example, alters communication.

Surgery on the tongue, oropharynx, hypopharynx, or mandible can alter or prevent swallowing.

This type of surgery is best performed in institutions that can provide the full range of rehabilitative services.

Contraindication. Surgery for a cure is generally contraindicated in patients with distant metastases.

Radiation therapy

Radiation alone is adequate treatment for many early lesions.

It can provide a cure without the functional or cosmetic deficits associated with surgery.

It can treat multiple primary lesions simultaneously.

It can prophylactically treat regional nodes that are clinically negative.

FIGURE 19-1 Basic algorithm for treatment of head and neck cancer.

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Planned postoperative radiation can significantly increase the survival rate for patients with advanced lesions.

Recent studies show that the response to radiation therapy can be enhanced (even in advanced tumors) by using hyperfractionation (more than one daily treatment) and concomitant chemotherapy. These techniques increase the risk and severity of local side effects.

Complications of radiotherapy include mucositis, xerostomia, loss of taste, dermal and soft tissue fibrosis, dental caries, and bone and soft tissue necrosis. A dental examination is required before radiotherapy. Dental treatment during and up to 2 years after radiotherapy can be hazardous because of decreased vascularity and consequent delayed healing.

Chemotherapy is not curative as a single treatment modality in head and neck squamous cell carcinoma. Cisplatin is the most effective agent. It is often combined with 5-fluorouracil (5-FU), paclitaxel (Taxol), and other drugs. Methotrexate is also an effective single agent and is used primarily for palliation.

Chemotherapy is used in neoadjuvant treatment to reduce the tumor burden before radiation or surgery.

Chemotherapy is used with concomitant radiation therapy to increase response rates in advanced tumors.

Chemotherapy is being evaluated as adjuvant therapy to reduce recurrence rates.

Chemotherapy is used for palliation in patients with unresectable tumors or distant metastases.

E

Rehabilitation should be planned at the same time as treatment.

Cosmetic and functional defects are reconstructed at the time of the cancer resection whenever possible. The use of surgical flaps (see Chapter 26, I C) has greatly facilitated reconstruction. The flaps may be:

Local flaps (nasolabial, forehead)

Distant pedicled skin flaps (deltopectoral, omocervical)

Pedicled myocutaneous flaps (pectoralis major, latissimus dorsi, trapezius)

Free microvascular flaps

Prosthetic rehabilitation is necessary when portions of the maxilla, orbit mandible, or palate are resected.

When the larynx is removed, intensive rehabilitation is required to re-establish the voice.

Initially, patients are taught to speak with an electrolarynx that is applied to the neck surface and positioned intraorally or incorporated within dentures.

Later, patients learn to speak with regurgitated air (esophageal speech) or with a prosthesis (a one - way valve) placed in a surgically created tracheoesophageal fistula.

Many patients who undergo partial laryngectomy, pharyngectomy, or glossectomy require training to facilitate swallowing and to avoid aspiration.

II Cancer of the Neck

A Anatomy

Divisions. The neck is divided into anterior and posterior triangles.

The anterior triangle is bounded by the midline of the neck, the inferior border of the mandible, and the anterior border of the sternocleidomastoid muscle. It can be subdivided further into submandibular, submental, superior carotid, and inferior carotid triangles.

The posterior triangle is bounded by the posterior border of the sternocleidomastoid muscle, the anterior border of the trapezius, and the clavicle. It is divided further into supraclavicular and occipital triangles.

Lymphatic drainage

Fascial planes of the neck enclose the lymphatic system.

The superficial fascia is subcutaneous and envelops the platysma.

The deep fascia has three parts:

Superficial layer, which invests the sternocleidomastoid and trapezius muscles

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Pretracheal fascia (middle)

Prevertebral fascia (deep)

There are approximately 75 lymph nodes on each side of the neck.

Most lie within the deep jugular and spinal accessory chains.

The jugular chain is divided into superior, middle, and inferior groups.

Cervical lymph node levels:

Level 1 contains the submental and submandibular nodes.

Level 2 is the upper third of the jugular nodes medial to the sternocleidomastoid muscle, and its inferior boundary is the plane of the hyoid bone (clinical) or the bifurcation of the carotid artery (surgical).

Level 3 describes the middle jugular nodes and is bounded inferiorly by the plane of the cricoid cartilage (clinical) or the omohyoid (surgical).

Level 4 is defined superiorly by the omohyoid muscle and inferiorly by the clavicle.

Level 5 contains the posterior cervical triangle nodes.

Level 6 contains the paratracheal and pretracheal nodes.

B Evaluation of a neck mass

A workup for malignancy should be undertaken in all adults with a persistent neck mass.

History and physical examination. A careful history is taken, and the head and neck are examined for evidence of a possible primary cancer (see I C).

Diagnosis. If the primary cancer is not identified on the initial examination, the workup that follows should include:

A chest x-ray, barium swallow, and computed tomography (CT) scan of the neck are indicated in most patients. Magnetic resonance imaging (MRI) of the neck and other x-ray or nuclear medicine studies are guided by findings on the history and physical examination.

MRI is particularly useful in defining deeply invasive tumors of the tongue, pharynx, and larynx.

CT of the sinuses can be used to search for primary tumors. CT or MRI of the chest and abdomen are often used for staging.

Panendoscopy (direct laryngoscopy, esophagoscopy, bronchoscopy, and nasopharyngoscopy)

If the result of the endoscopic survey is negative, random biopsies of the nasopharynx (right, middle, and left) are performed. A random biopsy of the tongue base or a tonsillectomy may also be worthwhile.

If all biopsies have negative results, the next step is to proceed with open neck biopsy and frozen section.

C Staging of metastatic neck disease

Stage N0: No clinically positive node

Stage N1: A single clinically positive node homolateral to the primary tumor and 3 cm or less in its greatest diameter

Stage N2a: A single clinically positive homolateral node larger than 3 cm but less than 6 cm in its greatest diameter

Stage N2b: Multiple clinically positive homolateral nodes, with none larger than 6 cm in its greatest diameter

Stage N2c: Bilateral or contralateral clinically positive nodes, with none larger than 6 cm in its greatest diameter

Stage N3: Any node greater than 6 cm in greatest diameter

D Treatment

If a primary cancer is identified and confirmed with biopsy, the metastatic neck disease is treated in conjunction with this primary cancer.

Types of neck dissection (Fig. 19 -2)

Radical neck dissection is an en bloc dissection of the cervical lymphatics.

It includes removal of the sternocleidomastoid muscle, internal jugular vein, or spinal accessory nerve.

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FIGURE 19-2 Types of neck dissection, including traditional neck dissection and various levels of modification. In a radical neck dissection (A), the sternocleidomastoid muscle, internal jugular vein, and spinal accessory nerve are removed. In the most conservative modification (B), only the fascial compartment with the lymphatic tissue is removed, and all of the structures are spared.

It is performed when squamous cell carcinoma is found in a neck mass with an unknown primary cancer or in conjunction with excision of the primary tumor.

Modified (functional, conservative) neck dissection removes the cervical lymphatics within their fascial compartments.

It spares the sternocleidomastoid muscle, internal jugular vein, and spinal accessory nerve.

Indications include:

Elective neck dissections

A single node less than 3 cm in diameter that is to be treated postoperatively with radiation

Differentiated thyroid cancers with neck metastases

Simultaneous bilateral neck dissections

Segmental neck dissection refers to removal of less than all five nodal groups on one side of the neck (e.g., submandibular triangle dissection, supraomohyoid dissection)

Elective neck dissection refers to surgical treatment of NO disease.

There is controversy about when and whether to use elective neck dissection, because radiation therapy can provide prophylaxis for metastatic neck disease in many cases.

The choice between surgery and radiation usually depends on the treatment of the primary tumor.

In general, when elective neck dissection is performed, it is done for a primary cancer that has a 30% or greater chance of occult metastasis.

III Cancer of the Nasal Cavity and Paranasal Sinuses

A Anatomy

Basic structure

All sinuses are paired, and all are contiguous with the nasal cavity through their natural ostia.

The nose and sinuses are lined with a respiratory mucosa, which is pseudostratified columnar with goblet cells and cilia.

Lymphatic drainage is to the parapharyngeal or retropharyngeal nodes. Secondary lymphatics are the subdigastric nodes of the internal jugular chain.

B Classification

Location. Most tumors (59%) are in the maxillary sinus, 24% are in the nasal cavity, 16% in the ethmoid sinuses, and 1% in the frontal and sphenoid sinuses.

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Approximately 80% of the malignancies are squamous cell carcinoma.

Tumors that arise anteriorly tend to be well differentiated.

Tumors arising from the posterior nasal cavity and ethmoids are generally poorly differentiated.

Nasal and sinus cancers are locally invasive. Nodal metastases are unusual and tend to occur late, even with extensive local disease.

Approximately 10%–14% of the malignancies are adenocarcinomas , including adenoid cystic carcinoma.

Inverted papilloma is a benign tumor (see Chapter 18, IV B 2 c [2] [b] ). The reported incidence of malignant degeneration is approximately 2%. The incidence of associated malignancy in adjacent tissue is as high as 15%.

C Clinical evaluation

Presenting symptoms can include nasal obstruction; epistaxis; localized pain; tooth pain; cranial nerve deficits; a mass in the face, palate, or maxillary alveolus; proptosis; and trismus.

Diagnosis. The extent of the disease is determined by physical examination and radiographic studies.

A CT scan is useful for identifying bony erosions and orbital or intracranial extension.

MRI can be used to determine intraorbital and intracranial invasion.

Arteriography is useful in patients with skull base invasion or rare vascular tumors.

Most biopsies can be performed under local anesthesia.

D

Staging is available for maxillary sinus cancer.

Stage TX: Cannot be assessed

Stage T0: No evidence of a primary cancer

Stage T1: Tumor confined to the inferior antrum without bone erosion

Stage T2: Tumor confined to the superior antrum without bone erosion of the inferior or medial walls

Stage T3: Extensive tumor involving the skin of the cheek, the orbit, the anterior ethmoids, or the pterygoid muscles

Stage T4: Massive tumor involving the cribriform plate, posterior ethmoids, sphenoid, nasopharynx, pterygoid plates, or base of the skull