Oral+Cavity

Tumors of minor salivary origin Sarcomas Ameloblastomas The first level of lymph node drainage of the floor of the mouth is to the submandibular and subdigastric lymph nodes. The anterior portion of the tongue drains into submental nodes and the lateral portion of the tongue drains into the submandibular and upper jugular nodes. There are also lymphatics trunks that bypass this drainage and go directly to the mid-jugular lymph nodes. Drainage also enters contralateral nodes due to bilateral nodal drainage.6 [] [] Lymphatic drainage of the buccal mucosa is to the periparotid submandibular and submental lymph nodes.6 ||
 * **Epidemiolgy:** || * Although cancers of the head and neck region only account for five percent of all cancers reported yearly in the human body, oral cancer comprise roughly 30% of all head and neck cancers.
 * The most common cancer of the oral cavity is called squamous cell carcinoma and arises from the lining of the oral cavity.
 * Epidemiology of oral cancers strongly reflects exposure to certain environmental agents, mainly tobacco and alcohol.
 * Depending on age and sex the incidence varies of oral cavity and pharynx is 8.3 per 100,000.
 * Male’s incidence is higher in northern France, southern India, a few regions of Central and Eastern Europe and Latin America.
 * In the United States cancer of the oral cavity afflicts older patients more than younger and is three times more frequent in men than women.
 * Incidence rates are higher for African American men, with mortality rates doubling that of Caucasians 7.5/100,000 vs. 3.9/100,000.
 * Survival rates are 61% in whites versus 39% in African Americans.
 * New studies reveal that 4%-6% of oral cancers now occur at ages younger than 40 years old.1 ||
 * **Etiology:** || * Patients who have poor oral and dental hygiene.
 * There is a strong relationship between smoking and cancer of the oral cavity; identified as an independent risk factor in 80-90% of patients who present with cancer of the oral cavity.
 * Alcohol use is another high-risk activity associated with oral cancer. There is known to be a very strong synergistic effect on oral cancer risk when a person is both a heavy smoker and drinker. The risk is greatly increased compared to a heavy smoker, or a heavy drinker alone.
 * Ultraviolet radiation.
 * Herpes simplex virus (HSV) and human papilloma virus (HPV).2 ||
 * **Signs & Symptoms:** || Most cancers show up on the anterior surface on either side of the mouth. The most common of these is a non-healing wound on the tongue, in the floor of mouth or along the inner cheek. These can be painful, but in some cases do not cause significant discomfort. There may be bleeding from the area which occurs in an “on and off” manner. As the lesions increase in size, more symptoms occur. Complaints may include new or increased pain; pain with swallowing, ear pain, change in speech, uncoordinated swallowing, or a lump in the neck.3 ||
 * **Diagnostic Procedures:** || Oral cavity cancer evaluations begin with a careful head and neck examination and biopsy of the lesion. Radiographic examinations are optional for superficial lesions, but are essential in evaluating the extent of the primary disease, evaluation of mandible invasion, and evaluation of nodal metastasis.6
 * General **
 * History (alcohol intake, smoking, tobacco chewing)
 * Head and neck examination **
 * Check for palpation of the oral cavity and oropharynx
 * Mirror examination of the nasopharynx
 * Indirect laryngoscopy
 * Neck lymph node examination
 * Direct laryngoscopy
 * Biopsy of areas of interest
 * Laboratory Studies **
 * Blood counts, blood chemistry profile, urinalysis
 * Radiographic Studies **
 * Chest radiographs
 * Plain radiographs of the mandible
 * Optional positron emission tomography (PET), computed tomography (CT) or magnetic resonance imaging (MRI) scans ||
 * **Histology:** || Squamous cell carcinoma accounts for 95% of all oral cavity cases.7
 * Most are moderately differentiated.
 * Tumor grade has almost no prognostic value.
 * Adenoid cystic carcinoma
 * Mucoepidermoid carcinoma
 * Adenocarcinoma
 * Can arise in the oral submucosal tissues and from the bones.
 * Benign but locally invasive tumors that can arise in the manidble or maxilla. ||
 * **Lymph node drainage:** || The upper lip primarily drains to the submandibular lymph nodes, periauricular and periparotid lymph nodes. The lower lip drains to the submandibular and posteriorly to the subdigastric lymph nodes. The lymphatics of the lower gingiva drain to the sumandibular and subdigastric lymph nodes.6
 * **Metastatic spread:** || At the time of presentation it is uncommon to have cervical lymph node involvement. Other than glottic cancer the oral cavity has the lowest incidence of nodal metastasis in the head and neck region. In some cases blood-borne spread may occur, however many of these cases have cervical lymph node involvement at the time of presentation. There may be spread through direct extention the foloing chart shows the most common paths in the oral cavity.


 * 1) Lips
 * 2) Skin
 * 3) Commissure
 * 4) Mucosa
 * 5) Muscle

2. Gingiva


 * 1) Soft tissue and buccal mucosa
 * 2) Periosteum
 * 3) Bone and maxillary antrum
 * 4) Dental nerves

3. Buccal mucosa


 * 1) Side walls of the oral cavity
 * 2) Lips
 * 3) Retromolar trigone
 * 4) Muscles

4. Hard palate


 * 1) Soft palate
 * 2) Bone and maxillary antrum
 * 3) Nasal cavity

5. Trigone


 * 1) Buccal mucosa
 * 2) Anterior pillar
 * 3) Gingiva
 * 4) Pterygoid muscle

6. Floor of mouth


 * 1) Soft tissue, tonsils, and salivary glands
 * 2) Root of tongue
 * 3) Base of tongue
 * 4) Geniohyoid-mylohyoid muscles

7. Tongue


 * 1) Anterior two thirds of tongue
 * 2) Lateral borders
 * 3) Base and underside of tongue
 * 4) Floor of mouth

8. Soft palate

G1= well differentiated G2= moderately differentiated G3= poorly differentiated || T0 No evidence of primary tumor Tis Carcinoma in situ T1 2 cm or less T2 >2 but <4 cm T3 >4 cm  T4a (oral cavity) Invades adjacent structures (e.g., through cortical bone, into deep [extrinsic] muscle of tongue [genioglosus, hypoglossus, palataglossus, and styloglossus], maxillary sinus, skin of face) T4b Tumor invades masticator space, pterygoid plates, or skull base and/or encases internal carotid artery. Note: Superficial erosion alone of bone/tooth socket by gunguval primary is not sufficient to classify as T4.
 * 1) Tonsillar pillars
 * 2) Pharyngeal walls
 * 3) Hard palate
 * 4) Nasopharynx ||
 * **Grading:** || Tumor grading used in the oral cavity is:
 * **Staging:** || TX Primary tumor cannot be assessed

NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis N1 Metastasis in a single ipsilateral lymph node, <3 cm in greatest dimension N2 Metastasis in a single ipsilateral lymph node >3 cm but <6 cm in greatest dimension; or in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension; or in bilateral orcontralateral lymph nodes, none >6 cm in greatest dimension N2a Metastasis in a single ipsilateral lymph node > 3 cm but < 6 cm in greatest dimension N2b Metastasis in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c Metastasis in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3 Metastasis in a lymph node >6 cm in greatest dimension Mx Presence of distant metastasis cannot be assessed M0 No distant metastasis M1 Distant meetastasis Notes: Histologic examination of a selective neck dissection specimen should include 6 or more lymph nodes. A radical or modified radical neck dissection specimen should include 10 or more lymph nodes.

Stage I T1 N0 M0 Stage IIA T2a N0 M0  Stage IIB T1 N1 M0 or T2a N1 M0 or T2b N0-1 M0  Stage III T1-2 N2 M0 or T3 N0-2 M0  Stage IVA T4 N0-2 M0  Stage IVB Any T N3 M0  Stage IVC Any T Any N M11 || The 5 year survival for oral cavity cancer (excluding lip and tongue cancers) is 47%.5 An important prognostic factor is the extension of the tumor. The more it extends, the poorer the prognosis. In addition to this, with the increase in lymph node involvement there is a decrease in prognosis. The nodes that play a big role in these cancers are the cervical nodes, and there effect on survival may be effected by the extent upon detection. || Radiation is used when resection is not an option. Oftentimes a combination of surgery and radiation is conducted because it has been found that more extensive tumors are rarely cured by one of the modalities alone.4 Percutaneous interstitial brachytherapy implant in place. [] Intraoral cone in place on a patient's tumor. [] ||
 * **Radiation side effects** || * Patients receiving doses greater or equal to 35-45 Gy to the salivary glands will likely cause **Xerostomia** (dry mouth). This is a very detrimental side effect that can cause difficulty with oral hygeine (leading to teeth decay), can make chewing and swallowing more difficult, and can destroy the ability to taste.
 * A second side effect often seen in these cases is ** Osteoradionecrosis. ** This is due to the radiation to bone, and causes it to decay. If there is foreseen need for the removal of teeth or dental work, this should be completed before treatment to help minimize the severity of these side effects.4 Osteoradionecrosis is a factor that can become very serious especially when irradiating around the mandible.
 * Another effect is **Mucositis** with a tolerance dosing of approximately 20-30 Gy, increasing in severity with increasing doses. ||
 * **Prognosis:** || In regards to treating areas in the head and neck region, it becomes important to be aware of the treatment technique uses, the size of the target volume, the dose/fractionation, the location and extent of disease and the patient's overall health.4 These factors can all greatly influence the morbidity of the radiation treatments.
 * ** Treatment ** || Small squamous cell carcinomas originating in the oral cavity are generally resected if the functional and cosmetic result is satisfactory.
 * Anterior Tongue **
 * Usually resected
 * RT when lesions are medically inoperable (yields superior cosmetic and functional results)
 * Primary lesion and first echelon of nodes given 46 Gy
 * Fields reduced off cord and treated to 60 Gy
 * Posterior cervical nodes often treated with lateral electron fields
 * Boost may be delivered via an intraoral cone or an implant to 75 Gy
 * Floor of Mouth **
 * Small tumors usually treated with external beam therapy and an intraoral cone, or an interstitial implant
 * At a dose around 20 Gy, tumoritis (redness of the tumor) occurs, defining the extent of the tumor
 * Dosing to the primary lesion to about 70 Gy
 * Small floor of mouth lesions that are fixed to the mandible tend to be treated first with excision and then radiation
 * Post-op RT to 60 Gy
 * Lip **
 * Most commonly found on the lower lip
 * Small lesions treated via orthovoltage or electrons
 * lead cutouts used to protect surrounding tissues
 * More advanced lesions treated via photon beams and and interstitial implant boost
 * Dosing toatal of 65-70 Gy
 * Submental, submandibular, and subdigastric nodes included in primary volume if necessary
 * Via lateral fields
 * Retromolar Trigone and Anterior Faucial Pillar **
 * Surgical resection or radiation therapy
 * RT for early lesions; surgery reserved for salvage of radiation therapy failures
 * 20 Gy til tumoritis is reached, then anterior and lateral fields with wedges or anterior and posterior oblique fields with wedges to 45 Gy
 * Buccal Mucosa **
 * Small well-defined lesions treated with resection or radiation therapy (photon and/or electron beams)
 * Implant or intraoral cone for boost delivery
 * Dosing to 55-60 Gy with a 20 Gy boost (sparing the mandible)
 * Gingival Ridge **
 * Depends on the extent of the tumor, nodal involvement, and presence or absence of bone involvement
 * RT alone: lateral and anterior weddged fields
 * Local control rate is poor; surgery generally preferred
 * Pre/Post OP radiation to eliminate microscopic disease
 * Pre-Op dose: 45-50 Gy
 * Post-Op dose: 60 Gy
 * Radiation Therapy Techniques **
 * External Beam:
 * Opposed lateral portals include submandibular, subdigastric, and submental nodes
 * Superior border needs to be 2 cm above dorsum of the tongue
 * Posterior border needs to be 2 cm behind the sternocleidomastoid muscle
 * Inferior border needs to be at thyroid notch
 * Cervical node mets are treated with AP field with larynx shield to 4500 Gy then the posterior chain is treated with an electron energy as a boost to spare the spinal cord
 * When considering fields and dosage it is very important to minimize exposure to the manible
 * If margins are close or positive or if there is any extracapsular extension in the cervical nodes an additional 6 Gy is given with reduced fields
 * Dosage:
 * Micoscopic Disease > 55-60 Gy
 * Small T1 and T2 Tumors > 65-70 Gy
 * Large T3 and T4 Tumors > Higher dose if Radiation used alone
 * Post- Op > 60 Gy
 * Interstitial Irradiation:
 * Most common technique: Percutaneous afterloading with angiocatheters and iridium 192
 * Cover tumor with .5- 1 cm margin
 * Low-dose rate of 4.5- 5 Gy an hour
 * Good results achieved for small T1 and T2 tumors alone or with external beam
 * Local control for patients with microscopic tumor at the surgical margins
 * Intraoral Cone:
 * Most optimal with lesions in the anterior tongue or anterior segment of the floor of the mouth
 * 250 KeV or electron beams of 6-12 MeV
 * ** TD 5/5: ** || [[image:uwlclinicaloncology2010/td5-5.jpg caption="td5-5.jpg"]] ||
 * **References:** || # Oral Cavity Cancer. American Head and Neck Society. Available at: []. Accessed May 20, 2012.
 * 1) Oral Cancer. Wikimedia Foundation, Inc. Available at:[]. Accessed May 20, 2012.
 * 2) Chao KSC, Perez CA, Brady LW. Pituitary. Radiation Oncology Management Decisions. Philadelphia, PA: Lippincott Williams & Wilkins; 2002: 223 -233, 1008-1017
 * 3) Bentel GC. Radiation Therapy Planning. 2nd ed. The McGraw-Hill Companies; 1996: 268-294.
 * 4) Rubin P. Clinical Oncology: A Multidisciplinary Approach for Physicians and Students. 8th edition. Philadelphia, PA: W.B. Saunders Company. 2001. 421-471.
 * 5) Perez CA, Brady LA, Halpern EC, Schmidt-Ullrich RK. Principles and Practice of Radiation Oncology. 4th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2004.
 * 6) Hoppe RT, Phillips TL, Mack III M. Leibel and Phillips Textbook of Radiation Oncology. 3rd ed. Philadelphia Pa: Elsevier Saunders; 2010. ||

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