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Removal of the involved vocal fold by traditional techniques or by carbon dioxide laser yields equivalent local control.

Some glottic lesions that involve the anterior commissure may be treated by hemilaryngectomy (vertical laryngectomy) because of the increased risk of cartilage involvement.

Some small lesions of the tip of the epiglottis can also be treated with limited surgical resection.

Large supraglottic tumors are treated with a supraglottic (horizontal) laryngectomy. This procedure spares the true vocal folds but removes the epiglottis, aryepiglottic folds, and false vocal folds.

For transglottic tumors (supraglottic tumors that spread to a true vocal fold), a suprahemilaryngectomy may be considered. Radical neck dissection, radiation, or both are often necessary because nodal metastases (30% of which are occult) are found in 55% of supraglottic cancers.

T3 and T4 lesions usually require a total laryngectomy , often combined with radical neck dissection. Postoperative radiotherapy is usually indicated (Fig. 19 -5).

Verrucous carcinoma is treated surgically by using a conservation laryngectomy, when possible. There is no need for elective radical neck dissection, and radiotherapy has been implicated as one cause of anaplastic transformation.

Current adjuvant chemotherapy protocols achieve cure rates comparable to those for traditional combined therapy and allow some patients to avoid total laryngectomy. Figure 19 -6 shows a protocol example.

G Prognosis

is better for patients with laryngeal cancer than with cancer of other head and neck sites. Five-year survival rates by stage are as follows:

Stage T1: 85%–90% with surgery or radiation

Stage T2: 80%–85%

Stage T3: 75%

Stage T4: 30%

IX Cancer of the Ear

A Anatomy

Basic structure. The tympanic membrane separates the external canal from the middle ear. The portions of the ear most susceptible to tumors include the external ear (pinna), external auditory canal, and middle ear. The mastoid and other parts of the temporal bone may also be involved.

Lymphatic drainage of the external ear and canal is anterior through the parotid, posterior to the mastoid nodes, and deep to the jugulodigastric nodes.

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FIGURE 19-5 A: Total laryngectomy specimen ready for removal, attached only to the tongue base. B: Pharyngeal defect following total laryngectomy. Closure is usually accomplished in layers in a T fashion.

B Classification and etiology

Cancer of the ear is rare.

The etiology has been related to thermal burns, chronic suppurative infection, and exposure to radium. Cancer of the pinna may come from actinic radiation.

Approximately 86% are epithelial cancers. Basal cell carcinomas comprise 8%; melanoma and adenocarcinoma comprise 2% each; and rhabdomyosarcoma and spindle cell sarcoma comprise 1% each. Other malignancies, such as osteogenic sarcoma, are rare.

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FIGURE 19-6 Example of organ-sparing neoadjuvant chemotherapy protocol.

Approximately 80% of ear cancers arise on the auricle, 15% in the external canal, and 5% in the middle ear.

Lytic lesions deep in the temporal bone should be worked up as possible metastases and may be from an adenocarcinoma, hypernephroma, melanoma, or other primary tumor.

C Clinical evaluation

Presenting symptoms

Most ear tumors present as an infected, painful, chronically draining ear.

If a mass is present in the external canal, it is usually friable.

Vertigo and facial paralysis are ominous signs.

Diagnosis

Biopsy. When cancer is suspected, the mass is biopsied under controlled conditions. Significant hemorrhage may occur.

CT and MRI scanning are necessary in most cases to evaluate the extent of tumor invasion.

D Treatment

Cancers of the auricle can usually be treated with wedge excision.

In deeper, more advanced cancers, radical surgery provides the best chance for a cure.

Tumors of the canal that are at least 5 mm lateral to the eardrum can be treated by excision of the external canal.

Cancers that impinge on the tympanic membrane without middle ear invasion are treated with partial (lateral) temporal bone resection. This procedure removes the external canal, eardrum, incus, and malleus, while sparing the facial nerve.

Cancers that involve the middle ear or pneumatized spaces are probably treated best by total en bloc temporal bone resection.

Radiation therapy has not produced satisfactory cure rates and is used best to treat recurrent or residual disease.

Combined therapy may be indicated in some cases.

E Prognosis

Results are difficult to evaluate because of the small number of cases reported.

For patients requiring temporal bone resection, 5-year survival rates range from 25%–35%. However, many of these operations have transgressed the tumor, leaving gross tumor behind. The newly described en bloc procedure should improve these statistics.

For lesions confined to the pinna, an 80% cure rate can be expected after treatment.

X Cancer of the Skin (see Chapter 26, II C, D, E, F)

Cancers of the skin account for 25% of all cancers, and squamous cell carcinomas account for 30%.

A Basal and squamous cell carcinomas

Basal cell carcinoma accounts for 60% of skin cancers, and squamous cell carcinoma accounts for 30%. P.388

Etiology

Sunlight

Radiation

Arsenic

Burns, scars

Genetic disorders (xeroderma pigmentosum, basal cell nevus syndrome, albinism)

Clinical evaluation

Skin cancers usually present as slowly enlarging cutaneous or subcutaneous lesions. Some lesions form nonhealing ulcers.

Nodal metastasis is uncommon.

Treatment. Therapy includes electrodesiccation, curettage, cryosurgery, excision, Mohs' surgery, radiation, and topical fluorouracil.

Surgical excision is preferred for squamous cell carcinoma because it allows removal of a margin.

Basal cell carcinomas of the nasolabial folds, medial and lateral canthi, or postauricular regions are especially aggressive. They can invade multiple tissue planes and, therefore, require an extensive surgical resection.

Mohs' surgery involves the precise mapping and frozen -section control of the entire resection bed. It

is especially useful for cancers in areas known for aggressive patterns of spread and recurrence. It allows for early reconstruction because of reliable surgical margins.

Radiation therapy is usually reserved for advanced lesions in areas where surgical excision leaves a cosmetically unacceptable defect (e.g., the nose, eyelid, lip).

Radiation should probably not be used when tumors invade bone or cartilage.

All positive nodes should be treated with radical neck dissection or radiotherapy.

B Malignant melanoma

Epidemiology

Malignant melanoma accounts for 1% of all cancers.

Approximately 20%–30% of all melanomas arise in the head and neck.

Melanoma occurs predominantly in whites. It commonly occurs in people between 30 and 60 years of age and is rare in children.

Etiology

Sun exposure and heredity play important roles in the causes of melanoma.

Melanomas may arise from junctional nevi (see Chapter 26, II D 2 a).

These nevi are usually present at birth.

Nevi that undergo malignant transformation are usually in an irritated or exposed area.

Melanomas can also arise on the mucosal surfaces of the head and neck.

Pathologic variants include:

Lentigo maligna melanoma

Superficial spreading melanoma

Nodular melanoma

Staging is by depth of invasion.

Stage T1: Up to 0.75 mm deep

Stage T2: 0.76–1.5 mm

Stage T3: 1.51–3 mm

Stage T4: More than 3 mm

Treatment is by wide excision of the melanoma.

A radical neck dissection is performed for positive nodes.

A parotidectomy is added to the radical dissection for lesions of the anterior scalp, eyelids, auricles, and cheeks because the first -level lymphatic drainage is to the periparotid nodes.

Elective radical neck dissection is usually performed on patients with T3 and T4 tumors.

Radiation therapy is usually reserved for palliative treatment of recurrent disease.

Chemotherapy , primarily with dacarbazine, is used for disseminated melanoma.

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Prognosis

The survival rate is related to the depth of invasion.

T1 lesions have a 5-year survival rate of 90%; T4 lesions, 10%.

N0 lesions have a 5-year survival rate of 90%; N1 and N3 lesions, 10%.

The prognosis in patients with mucosal melanoma is extremely poor.

XI Lymphoma of the Head and Neck

A Epidemiology

Approximately 80% of all malignant lymphomas arise from nodes, many of which are in the head and neck. About 65%–70% of patients with Hodgkin's lymphoma have cervical lymph node involvement.

Extranodal presentation is rare in Hodgkin's disease but occurs in 20% of patients with non -Hodgkin's lymphoma.

B Classification

Non -Hodgkin's lymphoma is really a group of diseases, which are classified into favorable and unfavorable types on the basis of therapeutic response.

Favorable types include:

Nodular lymphomas

Well -differentiated lymphocytic lymphoma

Unfavorable types include:

Diffuse, poorly differentiated lymphocytic lymphoma

Diffuse histiocytic lymphoma

Diffuse undifferentiated lymphoma

Nodular histiocytic lymphoma

Hodgkin's lymphoma. The histology of Hodgkin's disease influences the prognosis.

Favorable types:

Lymphocyte predominant

Nodular sclerosing

Guarded type: Mixed cellular

Unfavorable type: Lymphocyte depleting

C Clinical evaluation

Presenting symptoms

The usual presentation is a single, enlarged cervical node.

The initial workup is aimed at discovering an extranodal primary lesion.

The enlarged node must be differentiated from squamous cell carcinoma.

Most lymphomatous nodes are firm and rubbery.

Non -Hodgkin's lymphoma typically presents in upper cervical nodes.

Hodgkin's disease is discovered in nodes throughout the cervical chain.

The most common sites of extranodal involvement in non -Hodgkin's lymphoma are in the head and neck, particularly in Waldeyer's tonsillar ring. Other sites include the nasal cavity, paranasal sinuses, orbit, and salivary glands.

Approximately 40% of patients with Hodgkin's lymphoma have systemic symptoms of fever, sweats, weight loss, and malaise.

Diagnosis is usually made by excisional biopsy of a lymph node.

If a possible extranodal source has been discovered, it should be biopsied first.

Endoscopy should always precede lymph node biopsy to rule out a primary epithelial tumor.

For a node biopsy, one of the largest nodes should be removed in its entirety.

Frozen -section diagnosis is of little value except to exclude squamous cell carcinoma.

D

Staging is aimed at determining the extent of spread of the lymphoma.

Further tests. After the diagnosis is made, all patients undergo a chest radiograph, CT scan of the abdomen, and bone marrow biopsy.

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A CT scan of the chest, intravenous pyelography, and lymphangiography are sometimes added, depending on the initial findings.

All patients with non -Hodgkin's lymphoma require staging radiologic studies of the abdomen, usually by CT or MRI.

Staging laparotomy is often necessary for patients with an early stage of lymphoma when treatment with radiotherapy alone is contemplated. Laparoscopy can be substituted when patients also receive chemotherapy.

Stages are as follows:

Stage I: Involvement of a single lymph node region or a single extralymphatic site

Stage II: Either of the following:

Involvement of two or more lymph node regions on the same side of the diaphragm

Localized involvement of an extranodal site and one or more lymph node regions on the same side of the diaphragm

Stage III: Involvement of lymph node regions or extranodal sites on both sides of the diaphragm

Stage IV: Diffuse or disseminated involvement of one or more distant extranodal organs

E Treatment

Patients with stage I or II Hodgkin's disease can be treated with radiotherapy alone.

Patients with more advanced stages are treated with MOPP (mechlorethamine, vincristine [Oncovin], procarbazine, and prednisone) chemotherapy , usually combined with nodal irradiation.

Treatment of non-Hodgkin's lymphoma is much less clear -cut.

In general, early stages (I and II) are treated with radiotherapy, and later stages (III and IV) are treated with chemotherapy.

Combined treatment with radiation and chemotherapy is usually used for advanced unfavorable lesions.

F Prognosis

Hodgkin's disease

Favorable prognostic factors include:

Localized disease

A limited number of anatomic sites

Absence of massive disease

A favorable histology (lymphocyte predominant and nodular sclerosing)

Survival rates

Stages I and II have 5-year, relapse -free rates of 80%–90%. The rate falls to 60%–80% in patients with advanced disease (stage III) treated with combined therapy.

Rates as low as 30% have been reported in stage IV lesions.

Non -Hodgkin's lymphoma

Radiation therapy for patients with stage I and II lesions yields 50%–70% cure rates.

With more advanced lesions, patients with a favorable histology can have a 60%–70% 5-year survival rate and a 30% cure rate.

Patients with an unfavorable histology face a 24%–40% 5-year survival rate with little chance for a cure.

XII Unusual Tumors

A

Chemodectomas (paragangliomas) arise from chemoreceptor tissue.

They are rarely malignant (2%–6% are malignant), but they have a propensity for extensive local invasion.

Paragangliomas are often multicentric and associated with other malignancies.

Location. They are found in the carotid body, ganglion nodosum of the vagus nerve, aortic arch, and jugular bulb, and they are also found within the middle ear, orbit, nose, nasopharynx, or larynx. Morbidity and mortality depend on the type and extent of the tumor.

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Carotid body tumors usually present as slow -growing, painless neck masses.

Characteristics

Approximately 3% are bilateral. This tumor increases to 26% in patients with a familial tendency for paragangliomas.

Large tumors can cause dysphagia, airway obstruction, and cranial nerve palsies.

The mass may be pulsatile and may have a bruit.

Diagnosis is by angiography , which shows a tumor blush at the carotid bifurcation that splays the internal and external carotids.

Treatment is by surgical excision. Large tumors may require carotid bypass.

Glomus jugulare and glomus tympanicum tumors

Characteristics

Glomus jugulare tumors arise in the jugular bulb. They can invade the middle ear, labyrinth, and cranium. They commonly affect multiple cranial nerves (CNs), especially

CN VII, CN IX, CN X, CN XI, and CN XII.

Glomus tympanicum tumors arise in the middle ear, along the tympanic nerve. Most patients have pulsatile tinnitus and present with an aural “polyp” or a middle ear mass that can be seen with pneumatic pressure on the tympanic membrane. Hearing loss and vertigo are common.

Other rare sites of glomus tumor formation are along the vagus nerve in the neck

(glomus vagale) and in the larynx.

Glomus tumors present predominantly in the fifth decade of life or later and occur rarely in children.

Evaluation includes angiography, retrograde jugular venography, and CT scan. Biopsy should be avoided.

Up to 10% of patients with a glomus tumor will have associated bilateral glomus tumor, carotid body tumor, thyroid carcinoma, or other neural crest tumors.

Four-vessel carotid arteriography should be done.

Some tumors have endocrine activity that can lead to serious problems such as hypertensive crises during anesthesia. Serum and urine tests should be obtained to screen for endocrine activity and should also include screening for catecholamine, vanillylmandelic acid, and metanephrine.

The treatment of choice is surgical excision.

This procedure is easily carried out for small tympanicum tumors but can carry significant morbidity in patients with large tumors because of intracranial extension, hemorrhage, facial paralysis, and recurrence.

Glomus tumors are radiosensitive but not radiocurable.

New skull base surgical techniques have rendered essentially all lesions in this area resectable, and radiation should probably be reserved for recurrences, minimal residual disease, and patients who are physically unfit for surgery.

B

Other rare malignant vascular lesions are found in the head and neck.

Angiosarcomas arise from the vascular endothelial cells.

Characteristics. They grow quickly, extend through the dermis, and frequently metastasize. The most common site on the head or neck is the scalp.

Treatment. The only chance for a cure is complete excision.

Hemangiopericytoma arises from the pericytes of Zimmermann, which are wrapped around precapillary arterioles.

Characteristics. Approximately 25% are found in the head and neck. They are locally invasive and display an inconsistent malignant potential. Distant metastasis is not uncommon, but nodal spread is rare.