Head and neck cancer Diagnosis and Staging

The identification and appropriate management of premalignant mucosal lesions in the head and neck are important aspects of patient management that have major impact on overall survival rates. Since stage (extent) of disease at the time of diagnosis is the most important prognostic factor in the treatment of HNSCC, the identification and early treatment of small cancers correlate with excellent survival statistics. Most early premalignant changes or in situ carcinomas of the oral mucosa occur as red (erythroplasia) or white (leukoplakia) patches that should be readily apparent on visual examination. In areas less easily visualized directly, such as the larynx and hypopharynx, early lesions cause such symptoms as chronic hoarseness, chronic sore throat, referred otalgia, or dysphagia. These symptoms demand visualization of the involved structures by direct or indirect laryngoscopy.

Appropriate management of leukoplakia and erythroplasia lesions includes a high index of suspicion, particularly in high-risk individuals. Although both lesions are considered premalignant, erythroplasia lesions are of greater clinical concern since approximately half of these lesions contain carcinoma in situ (CIS) or invasive cancer. Additionally, often erythroplasia and leukoplakia may coexist. Erythroplasia mandates biopsy to rule out invasive cancer.

The management of erythroplasia and leukoplakia depends on the location, extent, and histology. The diffuse field effect and multifocal nature of the epithelial carcinogenic process support the need for effective chemoprevention. White lesions can be confused with mucositis; lichen planus; local tissue irritation from mechanical, thermal, or chemical trauma; histoplasmosis; candidiasis; and other infectious processes. Lesions that persist despite the removal of local irritating factors or that are associated with ulceration, vertical growth, induration, a recent change in size, or pain should be sampled by biopsy and/or excised. Topical supravital staining with toluidine blue of suspicious lesions can be helpful in identifying areas for biopsy and in screening high-risk populations.

Dysphagia, odynophagia, otalgia (referred), hoarseness, mucosal irregularities and ulceration, pain, weight loss, and the presence of an un-explained neck mass are the common presenting complaints of invasive HNSCC. The predominant symptoms vary with the site: chronic dysphagia or odynophagia (for 6 weeks or even less) demands thorough visualization of the oropharynx, hypopharynx, and esophagus; chronic hoarseness demands visualization of the larynx; chronic unilateral serous otitis media in an adult is a result of cancer of the nasopharynx blocking the Eustachian tube until proven otherwise; and unilateral Nasal polyps, nasal obstruction, or epistaxis is a common presenting sign of nasal cavity or paranasal sinus neoplasm. A firm or hard unilateral neck mass represents cancer until proven otherwise. In persons older than 20 years, such a mass represents neoplasm more than 80% of the time, and 80% of these neoplasms are due to metastatic spread from an UADT primary.

In patients presenting with a suspicious neck mass, a complete head and neck examination usually reveals the primary malignant tumor. If it does not, a thorough search for occult primary cancers both above and below the clavicles is warranted. Technologic advances in fiberoptics and in flexible and rigid endoscopes now provide excellent upper airway visualization that previously required special skills in indirect mirror examination. Endoscopic evaluation should include the nasopharynx, oropharynx, hypopharynx, larynx, and upper esophagus. Endoscopic evaluation should be accompanied by a barium swallow and chest radiography. Most commonly, occult primaries responsible for neck metastases occur in the nasopharynx, tongue base, tonsil or hypopharynx. In the absence of an identifiable mass, directed biopsies of these sites are indicated during endoscopic evaluation. Metastasis to a solitary left supraclavicular lymph node (Virchow node) is occasionally seen with infraclavicular cancer, especially colon cancer. Generally, metastatic supraclavicular masses derive from breast, lung, or infradiaphragmatic neoplasms. Thyroid malignancies may also metastasize to this area. Three-dimensional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) is frequently used to supplement the clinical evaluation and staging of the primary tumor and regional lymph nodes. More recently, positron emission tomography (PET) has gained some support in the identification of occult primaries.

Only after a thorough search for a primary tumor has been completed should a neck mass undergo biopsy. We recommend fine-needle aspiration (FNA) biopsy. If an excisional biopsy is required because FNA was inconclusive or not feasible, then the surgeon and patient should be prepared for definitive neck dissection if the mass should prove to be metastatic squamous cell carcinoma. The potential ramifications of false-negative results on FNA are inherently obvious. Accuracy of the cytologic interpretation of the aspirate is directly dependent on the skill and experience of the pathologist.

Staging criteria for cancers arising in the UADT, paranasal sinuses, and salivary glands have been developed by the American Joint Committee on Cancer (AJCC). The criteria undergo regular reevaluation and modification. The stage groupings used for head and neck cancer are based on T (primary tumor), N (regional node), and M (distant metastasis) designations. Because of variations in the growth, behavior, and prognosis of head and neck cancers according to site of origin and extent, differences exist in the staging criteria for each anatomic site. Staging criteria for the primary lesion are site specific. However, except for tumors arising in the nasopharynx, there is uniformity in the nodal staging criteria and stage grouping (

Tables 90-1 and

90-2).

Careful documentation of tumor extent and accurate staging classification are also important for the comparison of the results of different treatment regimens. Accurate evaluation of the results of a given treatment or the efficacy of new treatment strategies requires comparisons with patient groups with tumors of similar extent and behavior. Restaging after treatment or for recurrent cancers must be clearly designated and separate from the primary staging of previously untreated cancers. Postsurgical, or pathologic, staging is gaining importance in the primary treatment of head and neck cancers because of the increasing use of postoperative radiation therapy and/or adjuvant chemotherapy for patients with locally aggressive tumors or extracapsular spread into the soft tissues of the neck.

It should be noted, however, that as good as the widely accepted AJCC staging system is for the head and neck, it still falls short in that it too often fails to distinguish between deeply infiltrative tumors and those that are superficial or exophytic. Experience shows that this distinction is an important one and can have a significant impact on survival.

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Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD