Diagnosis

The diagnostic evaluation of a patient with oral carcinoma consists of the history and the physical examination, histopathologic tissue diagnosis, and imaging—when indicated.

The clinical history begins with the present illness and includes the duration and location of symptoms such as non-healing ulcer, mass in the oral cavity or neck, pain, bleeding, and any symptoms of cranial nerve deficits. A thorough exploration of the patient's past medical and surgical history, and the review of systems yield operative risk data. A thorough history of etiologic risk factors for squamous carcinomas not only reflects the patient's relative risk of malignancy but also suggests factors that affect the patient's overall health, fitness for surgery and emotional state. Current and distant abuse of tobacco and alcohol are critical factors and may be underreported by the patient. In many parts of the world the use of oral chews ("pan," betel nuts, etc.) is the chief etiologic factor.9 These may contain tobacco, slaked lime and other irritants and may be retained in the oral cavity nearly constantly. An occupational exposure to heavy metals such as nickel,10 and previous radiation exposure to head and neck are other important risk factors of head and neck cancer that are elicited in the history.

The social history impacts strongly on the patient's ability to comply with and tolerate treatment and rehabilitation programs, and these issues are resolved during the treatment planning phase. The family history reflects any familial tendencies toward malignant disease and completes the historical data.

A complete examination of the head and neck is performed to assess the precise location and extent of the primary tumor, identify regionally metastatic disease and to rule out multiple primary malignancies. Grossly, the earliest cancers may present as nonulcerous white or red patches. More advanced oral squamous cell carcinomas (SCC) present as mucosal lesions, although occasionally an SCC may present as predominantly submucosal with little or no mucosal involvement. Firm submucosal lesions are often minor salivary gland neoplasms. SCC may be ulcerative and invasive, fungating and exophytic or both (Figure 5-3). They may arise within prema-lignant lesions such as leukoplakia or erythroplakia. The following characteristics of the lesion should be documented: appearance and character, location, size in centimeters, texture to palpation, mobility, proximity to surrounding structures—especially bone, and the estimated palpable thickness (superficial vs. deeply infiltrating).

Figure 5-3. A, An exophytic lesion involving the right lateral border of the tongue. B, An endophytic lesion of the right lateral border of the tongue.

Trismus suggests ominous pterygoid and masticator space involvement. The condition of the dentition should be noted as tumors may, as the first sign, displace or loosen teeth. The distance from the tumor to the mandible and the mobility of the lesion in relation to the mandible are critical elements in determining the management of perimandibular cancers. A complete examination of the cranial nerves is performed, emphasizing sensation over the chin for mandibular nerve deficit, tongue mobility for hypoglossal nerve deficit, facial nerve function, palatal elevation and gag reflex, and function of the accessory nerve. A mirror or a flexible or rigid telescope is needed to document vocal cord mobility and to ensure that no lesions exist in the oropharynx, nasopharynx, endolarynx, and visible hypopharynx. Small lesions of the hypopharynx may only be visible by direct examination under anesthesia with the rigid laryngoscopes.

The neck should be thoroughly palpated for metastatic disease in the nodal groups at risk, and for other abnormalities of the great vessels and the thyroid gland which might impact treatment. Masses of the neck should be measured in centimeters, characterized for site (level), mobility, consistency, skin involvement, and proximity to vital structures. Normal neck structures commonly mistaken for metasta-tic masses include: the transverse process of C2 in the jugulodigastric region of thin patients, the scalene muscles, a tortuous carotid artery, a carotid aneurysm, a prominent carotid bulb, a cervical rib, and ptotic submandibular glands.

A complete general physical examination should be performed emphasizing the cardiovascular and pulmonary systems, which are commonly abnormal in this oral cancer population. The systemic effects of malnutrition or excessive alcohol intake should also be noted.

The history and physical examination with or without adjunctive imaging and histopathologic tissue diagnosis are sufficient to plan and execute surgical treatment for many patients with oral cancer. However, some patients will benefit from examination under anesthesia including direct palpation with or without biopsy, laryngoscopy, esophagoscopy, and bronchoscopy. The indications for examination under anesthesia include an inadequate assessment of the extent of the disease by history and physical examination and imaging, or the presence of symptoms referable to the trachea, larynx, hypopharynx and esophagus that need endoscopic assessment. It is not cost-effective screening to perform panen-doscopy on all patients with head and neck can-cer.1113 Symptoms suggesting lesions of the trachea, larynx, hypopharynx, or esophagus include: dyspha-gia, odynophagia, pain, hoarseness, hemoptysis or stridor. A careful history and meticulous head and neck exam is necessary to identify these lesions.

Evaluation of the deep extent of oral cancer often requires the use of imaging modalities. Imaging studies, however, will not adequately identify the superficial mucosal extent of disease, which must be established by visualization, palpation and biopsy. Plain radiographs such as panorex, dental films or a submental occlusal film may demonstrate gross bone involvement but do not show early cortical invasion.

Computed tomography (CT) is the most common modality employed to assess the extent of oral cancers (Figure 5-4). Advantages of CT include good soft-tissue discrimination and vessel identification and excellent definition of bone soft-tissue interfaces. CT scans are readily available and affordable. Cortical destruction and tumor in the alveolar canal and the bone marrow can be seen on CT. Special coronal reconstructions of dedicated mandible CT

What Dentascan
Figure 5-4. CT scan demonstrating an invasive carcinoma in the right half of the tongue with involvement of lymph nodes at level II.

scans (Dentascan) is particularly helpful in imaging the mandible. CT scans of the oral cavity should be combined with neck CT to assess for suspicious sub-clinical metastatic nodes. Axial and coronal views with bone and soft-tissue windows with contrast from the orbital floor to the base of the tongue as well as axial views of the neck are obtained. Disadvantages of CT scanning include radiation exposure, possible contrast dye sensitivity, dental amalgam interference, difficult positioning for coronal views, and no direct sagittal views.

Compared to CT scanning, magnetic resonance imaging (MRI) offers enhanced soft-tissue discrimination, excellent skull base and CNS assessment, sagittal views, and no radiation exposure (Figure 5-5). Disadvantages are that the examination takes longer, is more expensive, is poorly tolerated by some, and the black signal of bone makes cortical bone abnormalities difficult to see. An experimental imaging modality with promise is positron emission tomographic scanning. Positron emission tomography (PET) is a nuclear medicine study that demonstrates the difference in metabolism of radiolabeled glucose molecules between normal and malignant tissues. The clinical usage of this modality is currently not well-defined, but will likely aid in the diagnosis of recurrent and metastatic lesions.14

The appropriate metastatic evaluation of the patient with oral carcinoma is chest radiographs and serum liver function tests. The routine use of CT scanning of the chest, abdomen, and brain, or radionuclide bone scanning to evaluate oral cancer patients is not cost-effective and should be discouraged.

When all of the data from the history, physical examination, biopsy, imaging, and metastatic work-up are available, the tumor is staged according to the AJCC staging system (Table 5-1).

Was this article helpful?

0 0
10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

Get My Free Ebook


Post a comment