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Head and Neck Tumors
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Related narrative: Differential Diagnosis of Neck Masses Evaluation of Neck Masses Overview 1. Infectious/inflammatory processes should resolve within 6 weeks. 2. Any patient with a sore throat or hoarseness for one month should have a fiberoptic exam of the nasopharynx and laryngopharynx. 3. Most neck masses in children are benign, many in elderly are malignant (rhabdomyosarcoma can present as a neck mass in children.) 4. Most head and neck tumors are easily diagnosed on clinical exam. 5. Painless adenopathy (lymph nodes greater than 2 cm by measurement) should cause concern. 6. Malignant characteristics include: short duration, rapid growth, hard, fixed, rubbery (lymphoma), solitary (40% malignant.) History Have the patient describe time line: when started, change in size, change with antibiotics. Ask about sores in the mouth, sore throat, dysphagia, voice changes (hoarseness more than a month should have laryngeal exam), hemoptysis, oral bleeding, ear pain (otalgia referred from cancers in the tonsil, base of tongue, larynx, pharynx by referred pain involving CN IX.) Past history: smoking, smokeless tobacco, ETOH, exposure radiation, recent dental work (actinomycosis "lumpy jaw"), previous skin cancer, pet cats (cat-scratch disease), foreign travel, family history of cancer. Examination Examine the skin, scalp (skin cancers metastasize to parotid and upper neck ), mouth, oropharynx, fiberoptic exam of nasopharynx, hypopharynx, larynx. Must palpate the base of tongue and tonsils (squamous cell cancers often hide in the base of tongue lymphoid tissue, and can be felt as hard masses, and are friable (blood will be present on the finger after examination.) Neck exam: Mouth, tongue, and pharyngeal cancers metastasize to anatomical lymph node basins: nasopharynx to LN basin posterior to sternocleidomastoid muscle (level 5). Mouth, tongue, and oropharynx metastasize to levels anterior to sternocleidomastoid muscle (levels 1 , 2 & upper 3). Hypopharyngeal cancers metastasize to levels 3 and 4, and thyroid cancers metastasize to level 6 (pre-tracheal below thyroid gland.) Primary Assessment of Neck Mass & Differential Diagnosis 1. Congenital: 1st & 2nd branchial cleft cysts, thyroglossal duct cyst, lymphangiomas 2. Inflammatory: Viral, bacterial, fungal, mycobacterial, atypical mycobacterial, HIV, syphilis, toxoplasmosis, systemic lupus 3. Neoplasms (benign & malignant) • skin cancer (frequently metastates to parotid lymph nodes) • parotid tumors (80% benign, 20% malignant) • mouth and tongue squamous cell carcinoma (chronic ulcers & sores) • oropharynx carcinoma (ulcers and masses in tonsil, palate, base of tongue) • thyroid papillary carcinoma can present with lymphadenopathy before a thyroid mass is found • vascular origin : glomus vagale, carotid body tumor (listen for bruit) • schwannoma vagus nerve: firm mass moves anterior posterior with palpation • lymphoma: cervical adenopathy frequently associated with axillary/groin adenopathy (PET/CT total body scan will help with diagnosis) Diagnosis 1. CBC with differential, epstein bar virus, HIV, PPD, toxoplasmosis, barteonella antibody (cat scratch disease.) 2. MRI or CT/PET (MRI is preferred for evaluation of the pharynx above the cricoid, and CT below the cricoid). CT neck above the cricoid will be degraded by dental work 3. Perform MRI and CT/PET scans before a fine needle aspiration biopsy because the FNA changes the tumor characteristics on MRI and CT (may make a benign tumor appear malignant on scan.) 4. PET/CT fusion scan is now performed routinely as part of staging of head and neck cancer. 5. Fine needle aspiration biopsy should be performed before an open biopsy, and many times negates the need for open neck biopsy (85% sensitive, 99% specific). FNA biopsy with ultrasound is more accurate than without US, and recommended especially for parotid lesions which are deeper than expected on physical exam. 6. Open neck biopsy risks spilling of tumor cells. When performing an open neck node biopsy remove the entire node (excisional) vs. incisional biopsy which may spread tumor in the neck. 7. If a lesion is found in the tongue, mouth, oropharynx, a direct biopsy can be done in the clinic (do after CT/MRI scan since a biopsy may change the size of the lymph node by inflammation.) 8. If a lesion is seen in the nasopharynx, hypopharynx, or larynx, pan-endoscopy with biopsy must be done under general anesthesia (diagram tumor at time of endoscopy.) 9. A tonsillectomy is performed if a cancer of the tonsil suspected, and is often performed in squamous cell carcinoma metastatic to cervical lymph node of unknown origin. Discussion Review Congenital 1. Thyroglossal duct cyst • is a remnant of the thyroid embryologic descent from the foramen cecum of the tongue • an ultrasound to identify a normal thyroid below the larynx is recommended so that a partially descended normal thyroid is not removed • a portion of the mid-cricoid is removed along with the mass in order to remove the remnant tract, and prevent recurrence of the cyst • 1% chance of malignancy (80% papillary thyroid) 2. Branchial cleft cysts • a remnant of the 1st, 2nd, 3rd, 4th branchial pouches • first branchial cleft cysts present as masses in the pre-auricular area or angle of the jaw (confused with parotid neoplasms) • second & third branchial cleft cysts present along the anterior boarder of the sternocleidomastoid muscle and can connect to the pharynx (second most common) • fourth branchial cleft cysts can present as a mass of the thyroid (rare) Squamous Cell Carcinoma 1. Tobacco & alcohol are strong etiologic factors in head and neck cancer. Smokeless tobacco is a known cause of mouth cancer. 2. Radiation exposure is associated with thyroid cancer (epidemic after Chernobyl nuclear accident.) 3. Herpes virus (sexually transmitted) has also been implicated in oropharyngeal cancer and actually may have a better prognosis. 4. Squamous cell carcinoma originates from the mucous membranes of the aerodigestive tract presenting as a friable mass with ulceration. 5. Hypopharyngeal cancers arise from an area with low sensory innervations, and therefore often present with advanced disease before becoming symptomatic. A painless mid neck adenopathy is often the first presenting symptom. 6. A smoker (rarely non-smokers) with a chronic sore throat (over one month) associated with ear pain (referred pain from the tonsil, larynx, hypopharynx) has throat cancer until proven otherwise. 7. A patient with hoarseness more than one month should be examined for true vocal fold cancer. 8. Clinically positive lymph nodes decrease survival by 50%. 9. There is an 8% incidence of synchronous and 20% metachronous tumors (including lung and esophagus). Include Upper GI series and Chest XR as part of the cancer evaluation.
10. Cervical lymph node staging: 11. Management: all patients should be presented to a multi-disciplinary Tumor Board: guidelines @ http://www.cancer.gov/ (National Cancer Institute), and http://www.nccn.org/ (National Comprehensive Cancer Network) 12. Oral cavity cancer • stages 1 & 2 are treated with surgery and radiation with equal outcomes. • radiation therapy to 65 Gy increases survival. • stages 3 & 4 are treated with surgical resection of the primary cancer/neck dissection followed with radiation plus-minus chemotherapy. 13. Nasopharyngeal carcinoma • radiation therapy is the primary treatment, and neck dissection for persistent neck disease. • the more poorly differentiated tumors of nasopharynx respond better to irradiation. 14. Oropharyngeal (tonsil, palate, base of tongue) cancers. • chemo-radiation has replaced surgery and radiation as the primary therapy. • surgery (neck dissection and tumor resection) is performed for salvage of persistent disease after 12 weeks as detected on physical exam or scans (MRI or PET/CT fusion scan) • Chemo-radiation is indicated for non-resectable tumors with cisplatin & 5FU. 15. Laryngeal/Hypopharyngeal cancers • stage 1 and 2 cancers are treated with surgery or primary irradiation with equal results (radiation therapy gives better voice results). Total laryngectomy is reserved for radiation failure. • stage 3 tumors are treated with organ preservation protocols consisting of chemoradiation (cisplatin/5 FU/radiation.) Results in larynx preservation in 2/3 cases. • stage 4 cancers are treated with total laryngopharyngectomy followed by radiation plus-minus chemotherapy. Salivary Glands 1. Two percent of head and neck tumors 2. Malignancy risk is inversely related to salivary gland size: • Parotid gland (75 % of all salivary tumors) with 80% benign & 20% malignant. • Submandibular gland (10% of all salivary tumors) with 50% being benign & 50% malignant (45% malignant are adenoid cystic carcinoma.) • Sublingual gland glands (floor of mouth) and minor salivary glands on the palate (15 % of all salivary tumors) with 20% benign & 80% malignant. 3. Pathology • Pleomorphic adenoma (benign mixed tumor) is found in 80% of the benign tumors. • Warthin’s tumor (papillarycystadenoma lymphomatosum) represents 11 % of the benign tumors (10% being bilateral), and smokers have a 8X incidence. • Recurrence rate is much higher in pleomorphic adenomas removed by enucleation rather than the recommended parotidectectomy because pleomorphic adenomas have microscopic extensions beyond the tumor capsule. • Primary malignant tumors include: mucoepidermoid, adenoid cystic carcinoma, malignant mixed tumor (carcinoma ex pleomorhic adenoma), acinic cell carcinoma, and rarely squamous cell carcinoma (most squamous cell carcinomas are metastatic from skin cancer.) • Mucoepidermoid carcinoma (15% of all salivary gland tumors and most common parotid malignant tumor) is divided into three grades:
1) Low grade: focal invasion, 15% recurrence, rare metastases, 90% 5-year survival. • Adenoid cystic carcinoma is neurophilic and spreads along the perineurium. If pain or facial nerve paralysis is associated with a parotid or submandibular tumor, suspect adenoid cystic carcinoma. Adenoid cystic carcinoma is more common in submandibular gland. Can be confused with polymorphic low grade adenocarcinoma, and may need an experienced pathologist to tell the difference. Short term prognosis (5-10 year) is good but 20 year prognosis drops off dramatically, and the tumor often metastasizes to the lung. • Twelve percent parotid cancers present with facial nerve paralysis and are usually high grade mucoepidermoid (25% occult nodal metastases at diagnosis) or adenoid cystic. • Less than 3-year survival rate from onset of facial paralysis. • Squamous cell carcinoma from scalp, temple & ear metastasize to parotid (be suspicious of skin cancer metastasis in patients with a history of skin cancer, and “Irish skin”.) • Melanoma of the orbit can metastasize to the parotid lymph nodes. Presentation 1. Any mass in front or below the ear including upper neck at the angle of the jaw should be considered a parotid tumor. 2. Submandibular tumors present under the jaw. 3. Pain may be a sign of adenoid cystic carcinoma which tends to grow along facial nerve branches. 4. Facial paralysis is an ominous sign with poor prognosis. 5. Minor salivary gland tumors can present anywhere in the mouth, but occur more commonly on the soft and hard palate as a mass or ulcer. Adenoid cystic carcinoma is the most common cancer. Diagnosis 1. MRI is preferred over CT because of dental scatter artifact. 2. Fine needle biopsy is has a high sensitivity rate (not 100%) and should be done after the MRI since FNA can change the MRI tumor appearance. 3. Ultrasound-guided biopsy is preferred even in tumors which can be felt easily because the depth of the tumor can be deceiving. Treatment 1. Surgery (Parotidectomy, submaxillary gland excision, local excision with small margins of palate tumors) is the treatment of choice for benign tumors. 2. Parotidectomy, submandibular excision, and wide local excision of mouth/palate cancer is the treatment of choice for malignant tumors. Lymph node neck dissection with or without radiation therapy is added for most malignant tumors. 3. Radiation is not effective as primary therapy. 4. Parotidectomy (superficial or total) is the performed by first identifying the facial nerve at the stylomastoid foramen. • landmarks include the chonchal pointer and the tympanomastoid suture line. • a nerve monitor with nerve stimulator (NIM 2) is helpful in nerve identification and preservation. • many benign tumors abut the facial nerve and are dissected off the facial nerve. • many malignant tumors are also adjacent and many times adherent to the facial nerve. • if the malignant tumor can be “pealed off” the facial nerve, do so. Irradiation has been found to be effective for microscopic disease. • if there is pre-operative facial paralysis, obvious nerve invasion, and the tumor cannot be separated from the nerve, nerve sacrifice will be necessary with immediate nerve grafting. • do not rely on frozen section to identify malignancy in parotid tumors because of the high false positive rate. • if in doubt about the tumor pathology, do not sacrifice the nerve. You can always re-operate and sacrifice the facial nerve at a later date without harming the patient. • since negative margins of the facial nerve margins are desirable, consultation with an otologist may be needed to perform a mastoidctomy in order to obtain proximal tumor free margins. • facial nerve grafting can be performed using the opposite greater auricular nerve or sural nerve. • facial nerve injury (paresis) is common with parotidectomy but is usually temporary. • movement of the facial nerve by the nerve stimulator at the end of the case gives the surgeon confidence that there will be good recovery of any paralysis or paresis. 5. Frey’s syndrome (gustatory sweating) occurs when cut parasympathic innervations to the parotid gland attach to orphaned skin sweat glands after parotidectomy resulting in facial sweating with eating. Roll-on antiperspirants help decrease the symptoms. 6. Treatment of the Neck • Extent of lymph node dissection depends on disease found on physical exam, on CT/PET scan or MRI scan, and the anatomically draining lymph node basins. • Most high-grade parotid or submandibular tumors will require a modified radical neck dissection or radical neck dissection. • By definition, any lymph node dissection less than a radical neck dissection is a modified neck dissection. • Radical neck dissection refers to the removal of all ipsilateral cervical lymph node groups extending from the inferior board of the mandible superiorly to the clavicle inferiorly, from the lateral boarder of the sternohyoid muscle , hyoid bone, and contralateral anterior belly of the digastrics muscle medially, to the anterior border of the trapezius muscle laterally. Included are all lymph nodes from level I though V. The spinal accessory nerve, internal jugular, internal jugular vein, and sternocleidomastoid muscle are removed. • Modified radical neck dissection refers to the excision of all lymph nodes routinely removed by the radical neck dissection with preservation of one or more non-lymphatic structures: spinal accessory nerve, internal jugular vein, and sternocleidomastoid muscle. • Selective neck dissection refers to any type of cervical lymphadenectomy where there is preservation of one or more lymph node groups removed by radical neck dissection. Four subtypes include: a) supraomohyoid (LN levels 1-3); b) posterolateral dissection (LN levels 2-5); c) lateral neck dissection (LN levels 2-4); d) anterior compartment neck section (LN levels 6 or “central compartment”) Unknown Primary 1. An unknown primary is usually a squamous cell carcinoma found in a neck lymph node, and the primary source is not found on extensive examination of the mouth, oropharynx, nasopharynx, hypopharynx, and larynx. 2. Fiberoptic examination has facilitated examination of the above structures. 3. Physical examination should include bimanual examination which includes intra-oral examination and palpation of the base of tongue, and tonsils. Many times the cancer is hidden with the lymphoid tissue of the tonsil and base of tongue. 4. An MRI with contrast and or CT /PET fusion scan (8-42% sensitive) is obtained before any biopsies including fine needle aspiration. 5. If no tumor is found, a pan-endoscopy with selective biopsies of the nasopharynx, tonsil, base of tongue and hypopharynx is performed. Often a tonsillectomy is done at the same time if a tonsil cancer is suspected (for example the lymph node contains a cystic cancer). An esophagram should be done pre-esophagoscopy to evaluate for lesion of the esophagus including a zenker’s diverticulum. A Zenkers diverticulum can complicate a rigid esophagoscopy (for example: a mediastinal perforation with the esophagoscope.) 6. If an open neck lymph node biopsy is done for the diagnosis, and the node is found to be malignant on permanent pathology, neck dissection or radiation therapy should be done in a timely manner. Many authors recommend a neck dissection at the time of open neck node biopsy if a frozen section shows squamous cell carcinoma. 7. The tonsils are a common source (82%) for unknown primary metastasis along with the base of tongue. 8. Prognosis: 30-50% 5-year survival regardless of staging and treatment. Lymphoma 1. Presents in the neck commonly as bilateral cervical painless adenopathy, however unilateral disease can occur. 2. Can be slow growing or fast growing depending on the tumor type: Hodgkin’s lymphoma, non-Hodgkin’s lymphoma, Burkitts lymphoma, Malt lymphoma (suspect in Sjogrens disease with parotid mass.) 3. Lymphoma should be suspected in a younger, non-smoking individual with no mucosal lesions found in the mouth or pharynx. 4. CT/Pet whole body scan may pick up extra-cervical disease and further suggest lymphoma. 5. CT/Pet and MRI and examination may find extra-nodal lymphoma in the nasopharynx, tonsil and base of tongue. 6. Fine needle aspiration biopsy should include flow cytometry, and the pathologist should be alerted to your suspicion of lymphoma. 7. Open neck node biopsy is often necessary for diagnosis. If lymphoma presents as extra-nodal mass (base of tongue mass), diagnosis is made by direct biopsy. Take or send the specimen to the laboratory as fresh specimen (no formalin), and alert the pathologist about the possible lymphoma diagnosis so that special lymphoma protocols can be performed. 8. Treatment: Chemoradiation or radiation therapy alone is the treatment of choice. 9. Occasionally, in asymptomatic chronic lymphocytic lymphoma, no treatment is needed but followed by the oncologist. 10. Rhabdomyosarcoma can present as a lymph node mass in a child, and is diagnosed and treated similar to lymphoma. Author: David Thompson
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