CC
A 60-year-old White male presents to your office. He states, “I have been told I have a squamous cell carcinoma on my tongue.”
HPI
The patient noticed a spot on his tongue about a month ago. He reports that the lesion is painful, with radiating pain to the ear (this is a typical symptom of tongue carcinoma). He was initially seen by his general dentist and then referred to an oral and maxillofacial surgeon for a biopsy. The biopsy results described a squamous cell carcinoma (SCC).
PMHX/PDHX/medications/allergies/FH
The patient has a 45-year history of tobacco use. He also reports consumption of alcohol. (An association between tobacco and alcohol consumption and the development of SCC has been well established.) The patient does not report any other significant medical problems.
Examination
The examination of the patient with a diagnosis of SCC should include a complete head and neck examination. A neck examination is very important to evaluate for neck metastasis. Studies have shown that on initial examination of a known primary tumor, there is a 3% to 7% incidence of a synchronous tumor in the upper aerodigestive tract, especially in smokers. A nasopharyngoscopic examination is indicated to evaluate the subepiglottic and supraepiglottic regions, posterior oropharynx, and nasopharynx.
General. The patient is a well-developed and well-nourished male who appears his stated age, with no signs of cachexia.
Maxillofacial. The left tongue has a tumor, measuring approximately 4 cm × 2 cm, that feels endophytic and ulcerated. On palpation, it seems to have possibly crossed the midline ( Fig. 75.1 ). The rest of the oral cavity is free of lesions. The patient also has multiple necrotic teeth that are grossly carious. (Some patients may also complain of ear pain if the lesions are deep and involve the lingual nerve. When ear pain is present, perineural invasion cannot be ruled out until a final pathology evaluation.) Examination of the rest of the oral cavity, including the buccal mucosa, hard and soft palate, parotid, oropharynx, and nasopharynx, reveals no other abnormalities. Adenopathy is palpable in the submental and the left submandibular regions of the neck. The nodes feel firm but not fixed. (Fixed nodes could be a sign of extracapsular spread.)
Nasopharyngoscopy reveals no abnormal tissues in the posterior oropharynx, subglottic or supraglottic region, or nasopharynx. (Nasopharyngoscopy should be performed as part of the head and neck evaluation of tongue SCC.)
Imaging
The initial imaging modality for evaluation of a patient with SCC is a panoramic radiograph. This is a useful screening tool to evaluate for bony infiltration associated with the tumor. It also provides valuable information regarding the long-term prognosis of the remaining dentition because some patients may require extraction of carious or periodontally involved teeth before radiotherapy.
A computed tomography (CT) scan of the head and neck is the commonly used imaging study of choice to delineate the lesion and assess the neck for cervical lymphadenopathy (nodes >1.5 cm, with central necrosis, an ovoid shape, and fat stranding are indicative of nodal metastasis). Additional tests, such as magnetic resonance imaging and ultrasonography, can be used to assess the status of the cervical nodes.
Positron emission tomography (PET) scans are indicated for the evaluation of distant metastasis. This technology uses a 18F-fluorodeoxyglucose (FDG) marker to examine sites of increased glucose uptake that are seen with metabolically active cancer cells. In addition to helping to rule out distant disease, PET aids in clinical staging of the cancer. Clinical staging is helpful because a treatment plan can be worked up for the patient and adjuvant modalities recommended.
The current patient’s axial and coronal CT scans of the head and neck, with and without contrast, revealed a 4-cm, well-circumscribed lesion of the left lateral border of the tongue musculature. Some adenopathy was noted in the submental region bilaterally and in the left submandibular region. (Usually nodes are oval in shape; however, in patients with cancer who have lymph node involvement, the nodes are more circular. Nodes >1 cm in diameter should raise suspicion of metastatic disease. Central necrosis is another factor that correlates with a poorer outcome.) The PET scan performed with 18F-FDG showed a hypermetabolic area in the left tongue, coinciding with the clinical lesion, with a standard uptake value (SUV) of 17. (Some studies suggest a correlation between a higher SUV and more aggressive tumors.) Also noted were a single right level IB node, a single left level IB node, several left level IIA nodes, and a left level III node, all demonstrating associated FDG uptake. The largest node was a 1-cm × 1-cm level IIA lymph node demonstrating a maximum SUV of 5.4 ( Fig. 75.2 ). An SUV of greater than 3 has been shown to correlate with the increased metabolic activity associated with some pathologic conditions; however, clinical correlation must be completed.
In the current patient, the panoramic film showed that the condyles were seated on the fossa, with no bony invasion. In addition, several necrotic teeth with considerable periapical pathology were noted on the film.
Labs
A complete metabolic panel (CMP), complete blood count (CBC), and coagulation profile (prothrombin time, partial thromboplastin time, and international normalized ratio) are mandatory laboratory studies in the patients with cancer because of metabolic, electrolyte, and nutritional derangements that may accompany malignant disease. Liver function tests are obtained as part of the CMP and are important screening tests for liver metastasis and alcoholism. Other laboratory studies can be ordered based on the patient’s medical history.
In the current patient, the CBC, CMP, liver function test results, and coagulation studies were within normal limits.
Assessment
T2N2cM0 (tumor >2 cm, with multiple bilateral nodes with no distant metastasis), stage IV, oral SCC of the left lateral border of the tongue with a Broder’s histologic grade of III.
Treatment
The treatment of patients with SCC is site specific; surgical ablation with minimum 1- to 1.5-cm margins is the main modality of treatment. Most oral cavity tumors are approached intraorally; however, some tumors may need to be accessed extraorally via a transfacial approach. When the tumor is located in the mandible, the inferior border can be preserved (marginal mandibulectomy), depending on the degree of infiltration. However, when the cancellous portion of the mandible is invaded, segmental resection is required to maintain oncologic safety.
In the current case, several approaches were possible, including a transoral approach, a pull-through approach, a lip split mandibulotomy, and transoral robotic surgery, to obtain a cuff of normal tissue for the posterior tongue base margin. A transoral approach was used to excise the primary tumor. A common procedure that accompanies the removal of the tumor is neck dissection, or removal of the fibrofatty contents of the neck; this is done for treatment of cervical lymphatic metastases and for complete staging of the cancerous process. In the current patient, selective neck dissection was performed on the right (levels I–III) and left (levels I–V) sides. Bilateral neck dissection was performed because the tumor had crossed the midline and because the results of the PET scan were positive bilaterally. Vessel preservation was performed for a vascular free flap anastomosis (radial free forearm flap) to the facial artery and to the internal jugular vein.
The neck dissection procedure can be completed in many different ways. For the current patient, the following technique was used, because it is the preferred method at our institution.
Selective neck dissection (levels I–III)
After the patient had been prepped and draped, a surgical marker was used to delineate the incision site. Several variations of neck dissection incisions have been used historically ( Fig. 75.3 ). In this case, a straight-line neck incision was used, with the incision situated in a resting skin tension line midway between the angle of the mandible and clavicle, extending just slightly anterior to the auricle to the midline. (Any skin crease in the neck can be used, as long as it is ∼2 cm below the inferior border of the mandible to avoid damage to the marginal mandibular branch of cranial nerve [CN] VII.) A #10 knife blade was used to create an incision through the skin and subcutaneous tissue to visualize the platysma; this was sharply dissected with a Bovie electrocautery. Subplatysmal flaps were then raised to the level of the inferior border of the mandible superiorly and the omohyoid muscle inferiorly ( Fig. 75.4 ). (This inferiorly based flap can be extended to just above the clavicle if further dissection to level IV is required. Care should be exercised to preserve the greater auricular nerve. The external jugular vein should be skeletonized, ligated, and divided.) The superficial layer of the deep cervical fascia was dissected approximately 1.5 cm below the inferior border of the mandible to protect the marginal branch of the facial nerve. The capsule of the submandibular gland was dissected, and a subcapsular dissection was initiated superiorly to the inferior border of the mandible. Bovie electrocauterization was used to dissect the fascia to the anterior belly of the digastric muscle in the submental triangle; this was continued posteriorly to the submandibular gland. (The lateral limit of the dissection is the midline diatheses or the contralateral anterior belly of the digastric muscle.) The submandibular gland was then retracted inferiorly into the neck and circumferentially dissected along the contents of level I. The common facial vein and artery were identified and ligated as they traversed the posterior aspects of the gland. Anteriorly, they were again identified and ligated. (They are typically encountered on the medial side of the submandibular gland, thereby mobilizing the gland.) An Army Navy retractor was placed beneath the mylohyoid muscle to retract it superiorly. (The lingual nerve typically is visualized with the parasympathetic rami to the submandibular gland. The rami are transected with care to protect the lingual nerve.) The submandibular duct was then identified, skeletonized, and divided. (The entire contents of level I should be pedicled inferiorly on the digastric muscle. The fascia overlying the anterior border of the sternocleidomastoid (SCM) superiorly from the level of the digastric muscle inferiorly to the omohyoid muscle is then separated from the muscle with Bovie electrocauterization.) When the inferior surface of the SCM was dissected, the spinal accessory nerve was identified approximately 1 cm above Erb’s point and skeletonized. (When a clearance of level IIb is desired, the fascia above the CN XI is dissected deep to the level of the levator scapulae and splenius capitis. This fascia packet is then brought inferiorly beneath the nerve. The cervical roots form the posterior limit of the dissection, and fascia should be removed superficial to the nerve rootlets. Dissection deeper than the cervical roots should be avoided to prevent injury to the transverse cervical vessels and preserve the prevertebral fascia, which overlies the phrenic nerve and brachial plexus.) The fascia over the carotid sheath was then dissected over. (After the white roll is identified on the anterior border of the internal jugular vein, a #15 blade can be used to skeletonize the fascia from the vein sharply.) The branches of the internal jugular vein were identified on the anterior border and were skeletonized, ligated, and divided. (After this has been done, the fascia from the jugular sheath is advanced superficially from the posterior belly of the digastric muscle and the omohyoid muscle inferiorly to the level of the level I dissection, which is pedicled on the digastric muscle. As the dissection continues, the anterior jugular veins are identified and ligated. The specimens can now be removed from the patient and orientated by level.) Fig. 75.5 shows the neck after removal of the fibrofatty tissues from levels I through III.
