Signs and Symptoms
Head and neck cancer typically produces symptoms referable to the upper aerodigestive tract, including alterations in deglutition, phonation, hearing, and respiration. In particular, patients should be questioned about dysphagia, odynophagia, globus sensation, hoarseness, a change in the ability to form words, epistaxis, epiphora, otalgia, hemoptysis, stuffiness of the ears, and trismus. (Signs and symptoms of cancer at specific anatomic sites and subsites can be found in the respective discussions of these tumors.)
It is important to ascertain the duration and course (progression or improvement) of symptoms. Progression of disease is often noted during the evaluation and worsens the prognosis.
Screening and Diagnosis
Screening
Since many patients with head and neck cancer are unlikely to be engaged in the healthcare system, the means by which patient screening would be achieved remains a fundamental problem.
Diagnosis
The need for expeditious diagnosis of head and neck cancer and referral to skilled head and neck specialists cannot be overemphasized, as early diagnosis can lead to a reduction in mortality. One study suggested that in the 24 months prior to the diagnosis of head and neck cancer, patients had a median of 10.5 healthcare visits. These visits could have provided an opportunity to evaluate patients' symptoms and underscore the important role of dentists and primary care physicians in the early diagnosis of head and neck cancer.
History
Risk factors as outlined previously, including a history of tobacco and alcohol(Drug information on alcohol) use and environmental exposures, should be reviewed. Any adult patient with symptoms referable to the upper aerodigestive tract that have lasted longer than 2 weeks or with an asymptomatic neck mass should undergo a thorough examination with a high index of suspicion for carcinoma.
Physical examination
The physical examination is the best means of detecting lesions of the upper aerodigestive tract. Frequently, the initial assessment also will indicate the severity and chronicity of the disease. Due to the frequent occurrence of multiple primary tumors in patients with a head and neck tumor, careful evaluation of the entire upper aerodigestive tract is necessary at the time of diagnosis. The examination should always follow a systematic approach.
Skin/scalp. A search should be made for ulcers, nodules, and pigmented or other suspicious lesions. This part of the evaluation is frequently overlooked.
Cranial nerves. A cranial nerve evaluation is essential for any patient with a head and neck tumor or neck mass (which may be a manifestation of occult cancer). This evaluation should include assessing eye motion (cranial nerves [CN] III, IV, and VI); testing sensation of the face (CN V); examining the muscles of facial expression by having the patient grin, grimace, raise eyebrows, close eyes tightly, show teeth, and puff out the cheeks (CN VII); testing of hearing (CN VIII); assessing gag reflex (CN IX); evaluating vocal cord mobility (CN X); and having the patient fully abduct the shoulder (CN XI) and protrude the tongue (CN XII). Even the slightest abnormality may be helpful in identifying a primary tumor.
Eyes/ears/nose. The eyes, ears, and nose should be evaluated for any sign of mass effect, abnormal drainage/discharge, bleeding, or effusion.
Oral cavity. Halitosis may be the first indication of a lesion in the upper aerodigestive tract. The teeth, gingivae, and entire mucosal surface should be inspected. (Dentures should be removed.) The lymphoid tissue of the tonsillar pillars should be inspected and any asymmetry noted. Tongue mobility also should be evaluated.
The floor of the mouth, tongue, and cheeks should be palpated using a bimanual technique (one gloved finger inside the mouth and the second hand under the mandible). Palpation should be the last step of the examination due to stimulation of the gag reflex. Worrisome lesions should be biopsied.
Neck. A systematic examination of the neck consistently documents the location of any mass. Palpation is the cornerstone of the examination. It is performed by grasping the tissue and feeling the nodes between the thumb and long fingers. The relationship of a mass to major structures, such as the salivary gland, thyroid, and carotid sheath, should be considered.
Important qualities of a mass include location, character, tenderness, size, mobility, and associated thrill or bruit. The thyroid should be palpated.
Laryngoscopy. The nasopharynx, hypopharynx, and larynx should all be examined with care. The vocal cords should be visualized and their mobility evaluated. Mirror examination provides an overall impression of mobility and asymmetry, which may point to a hidden tumor. Nasopharyngoscopes permit a thorough inspection of the upper aerodigestive tract in the office setting. Attention should be focused individually on the piriform sinuses, tongue base, pharyngeal walls, epiglottis, arytenoids, and true and false vocal cords. Also, any pooling of secretions should be noted.
Examination under anesthesia with endoscopy. Approximately 5% of patients with head and neck cancer have a synchronous primary squamous cell cancer of the head and neck, esophagus, or lungs. Examination with the patient under anesthesia with endoscopy (which may include direct laryngoscopy, esophagoscopy, and bronchoscopy) and directed biopsy should be performed in all patients with an occult primary squamous cell cancer and in many patients with a known head and neck primary. Examination with the patient under anesthesia also can provide information regarding the extent of the tumor.
The most common sites of silent primary tumors are the tonsils, base of the tongue, and piriform sinuses. Tumors of the nasopharynx have become easier to identify with the increased use of flexible nasopharyngoscopy. Biopsies should be performed in common areas of silent primaries in addition to the primary anatomic sites associated with lymphatic drainage of any neck mass.
Laboratory evaluation
There are no specific screening laboratory tests other than preoperative studies performed in the diagnostic evaluation of most head and neck carcinomas. EBV, anticapsid antibodies, and serum immunoglobulin G are tumor markers for nasopharyngeal carcinomas.
Diagnostic imaging
Plain x-rays. Posteroanterior and lateral chest x-rays should be obtained in all adult patients to eliminate the possibility of occult lung metastasis or a second primary. A Panorex film may be helpful in delineating bony involvement in some cases of oral cavity lesions.
CT. The CT scan is probably the single most informative test in the assessment of a head and neck tumor. It may delineate the extent of disease and the presence and extent of lymphatic involvement. CT offers high spatial resolution; discriminates among fat, muscle, bone, and other soft tissues; and surpasses MRI in the detection of bony erosion. CT scans of the chest, abdomen, and pelvis sometimes may identify the site of an occult primary tumor presenting with a node low in the neck from lung and intra-abominal primary cancers (for left low neck presentations) if none has been identified. The value of including an abdominal and pelvic CT scan to look for distant metastatic disease in the absence of metastatic lung involvement is minimal.
MRI. An MRI may provide accurate information regarding the size, location, and soft-tissue extent of tumor. It provides limited information regarding bony involvement, unless there is gross involvement of the marrow space. Relatively greater sensitivity of MRI in relation to CT is offset by its decreased specificity. The main disadvantage of MRI is movement artifact, which is a particular problem in the larynx and hypopharynx. Gadolinium-enhanced MRI is probably superior to CT for imaging tumors of the nasopharynx and oropharynx.
PET. PET imaging has been evaluated in both primary and recurrent squamous cell carcinomas of the head and neck. 18F-fluorodeoxyglucose (FDG) is the most commonly used PET radiotracer. It enters the cell and undergoes the first step in glycolysis to produce FDG-6-phosphate, which reflects the metabolic rate of the tissue. The metabolic rate of malignancies is higher than that of most benign tumors or normal tissues. FDG imaging therefore has the potential to distinguish between benign and malignant processes, grade tumors, identify metastases, and diagnose tumor recurrence. In head and neck cancer, FDG imaging is capable of detecting clinically occult recurrences and in determining residual disease in the neck following definitive radiotherapy. It has proved less useful in identifying an occult primary site in the setting of a patient with a squamous cell carcinoma of an unknown primary site as well as evaluating for distant metastatic disease if conventional imaging of the lung does not show distant spread. PET imaging is currently most useful when registered with a CT scan (PET/CT).
In a multicenter, prospective study, published in 2010 by Lonneux et al, involving patients with newly diagnosed and untreated head and neck cancers, PET scanning results were discordant with standard imaging (eg, CT scan, MRI) in 43% of cases, and they altered the therapeutic plan in 14% of patients. Nuanced judgment in adding PET scanning to conventional imaging seems to be warranted.
Biopsy
Biopsies of the primary tumor often can be performed in an outpatient setting.
Punch or cup forceps biopsy. This procedure is important in the diagnosis of mucosal lesions. The biopsy should be obtained at the border of the lesion, away from areas of obvious necrosis.
Fine-needle aspiration. Fine-needle aspiration (FNA) is a useful diagnostic modality. Multiple passes are made through the lesion with a fine-gauge (22-gauge) needle while suction is applied. Suction should be released before withdrawing the needle through surrounding soft tissue of the neck. FNA has an associated false-negative rate as low as 7%. The diagnostic accuracy depends on the physician's skill and the cytopathologist's experience.
Cytology is particularly useful in distinguishing a metastatic squamous cell carcinoma from other malignant histologies. However, a negative result should not be interpreted as "absence of malignancy."
Core biopsy should not be performed on a neck mass, with the rare exception of a proven lymphoma.
Open biopsy. Open biopsy should be performed only when a diagnosis has not been made after extensive clinical evaluation and FNA is nondiagnostic. The operation should be performed only by a surgeon prepared to conduct immediate definitive surgical treatment at that time (which may entail a true neck dissection).
