Larynx Through Neck.docx

Larynx: Inflammations – most common disorder that affects the larynx (laryngitis):  May occur as the sole manifestation of allergic, viral, bacterial or chemical insult but is more commonly part of a generalized upper respiratory tract infections or the result of heavy exposure to environmental toxins (i.e. tobacco smoke)  May also be affected in systemic infections such as TB and diphtheria  Most are self-limiting but may be serious (exp. In infancy or childhood – laryngeal obstruction)  Laryngoepiglottitis (caused by B-hemolytic strep Haemophilus influenza) in infants/children w/ small airways may induce sudden swelling of the epiglottis/vocal cords it may be lethal.  Croup = laryngotracheobronchitis in children where inflammatory narrowing of the airway produces inspiratory stridor  Most common form of laryngitis (encountered in heavy smokers) predisposes to squamous epithelial metaplasia and sometimes overt carcinoma. Reactive Nodules (vocal cord nodules and polyps):  Most often in smokers or individuals who put stain on vocal cords  Singers nodules are bilateral lesions, polyps are unilateral  Morphology - nodules are smooth, rounded, sessile or pedunculated excrescences, generally only a few millimeters in the greatest dimension, located usually on the true vocal cords. Typically covered by a squamous epithelium that may become keratotic, hyperplastic or even slightly dysplastic. The core is a loose myxoid connective tissue that may be variably fibrotic or punctuated by numerous vascular channels. If on opposing cords they impinge on each other and the mucosa may undergo ulceration.  Characteristically change the character of the voice and often cause progressive horseness  Virtually never give rise to cancer Squamous Papilloma and Papillomatosis:  Laryngeal squamous papillomas are benign neoplasms, usually located on the true vocal cords  Form soft, raspberry-like excrescences rarely more than 1 cm in diameter  Histology – made up of multiple slender, finger-like projections supported by central fibrovascular cores and covered by an orderly stratified squamous epithelium.  When papillomas are on the free edge of the vocal cord, trauma may lead to ulceration that can be accompanied by hemoptysis.  Usually single in adults but often multiple in children (juvenile laryngeal papillomatosis)  Lesions are caused by HPV types 6 and 11 – do not become malignant but frequently recur

Carcinoma of the Larynx:  Sequence of Hyperplasia-Dysplasia-Carcinoma:  Spectrum of alterations is seen in the larynx: hyperplasia, atypical hyperplasia, dysplasia, carcinoma in situ, to invasive carcinoma.  Macroscopic – epithelial changes vary from smooth, white or reddened focal thickenings (sometimes roughened by keratosis) to irregular verrucous or ulcerated white-pink lesions that are similar in appearance to carcinoma  Likelihood of the development of an overt carcinoma is directly proportional to the level of atypia when the lesion is first seen.  Orderly hyperplasias have almost no potential for malignant transformation, but the risk rises to 1-2% during the span of 5-10 years with mild dysplasia and 5-10% with severe dysplasia. ONLY histologic evaluation can determine the gravity of the changes.  Changes are most often related to tobacco smoke – rick being proportional to the level of exposure (up to point of frank cancer, changes regress after smoking cessation)  Together smoking and alcohol increase the risk substantially  Factors that ↑ risk are: nutritional factors, asbestos exposure, irradiation and HPV infection.  Morphology:  95% of laryngeal carcinomas are typical squamous cell tumors.  Develop directly on the vocal cords, but it may arise above or below the cords, on the epiglottis or aryepiglottic folds, or in the pyriform sinuses (those confined within the larynx proper are termed intrinsic, those that arise/extend outside the larynx are extrinsic)  Squamous cell carcinomas of the larynx being as in situ lesions that later appear as pearly gray, wrinkled plaques on the mucosal surface, ultimately ulcerating and fungating  Degree of anaplasia of the laryngeal tumors is highly variable.  Sometimes massive tumor giant cells and multiple bizarre mitotic figures are seen.  With lesions arising from recurrent exposure to environmental carcinogens, adjacent mucosa may demonstrate squamous cell hyperplasia w/ foci of dysplasia or even carcinoma in situ.  Clinical Manifestation:  Manifests clinically by persistent hoarseness. Later may produce pain, dysphagia & hemoptysis  60% of cancers are confined to the larynx – better prognosis for these than tumors that have spread into adjacent structures.  Patients are extremely vulnerable to secondary infections of the ulcerating lesion.  Treatment - Surgery, irradiation or combination therapy  Mortality - 1/3rd of patients die of the disease. Usual causes of death are infection of the distal respiratory passages or wide-spread metastases and cachexia

Note the atypical lining epithelium and invasive keratinizing cancer cells in the submucosa. (Invasive b/c have extended past basement membrane).

Ear – rarely shorten lifespan but reduce quality of life. 

Most common aural disorders:  Acute and chronic otitis – most often involving the middle ear and mastoid, sometimes leading to cholesteatoma  Symptomatic otosclerosis  Aural polyps  Labyrinthitis Normal tympanic membrane ↑  Carcinomas – largely of the external ear Acute otitis media ↓ Chronic otitis media ↓  Paragangliomas – found mostly in the middle ear Inflammatory Lesions – otitis media (acute or chronic): asda  Occur mostly in infants and children  Typically viral and produce a serous exudate (R pic →), but may become suppurative with superimposed bacterial infection (MC – Strep. pneumoniae, nontypable H. influenczae & Moraxella catarrhalis)  Chronic otitis media (causes by repeated acute otitis media infections) are usually caused by Pseudomonas aeruginosa, Staphylococcus aureus or a fungus  Chronic infection has the potential to perforate the eardrum, encroach on the ossicles or labyrinth, spread into the mastoid spaces, and even penetrate into the cranial vault to produce a temporal cerebritis or abscess.  Otitis media in the diabetic person (when caused by P.aeruginosa) is especially aggressive and spreads widely causing destructive necrotizing otitis media Otosclerosis – abnormal bone deposition in the middle ear about the rim of the oval window (where footplate of stapes fits)  Usually affects both ears  1st - fibrous ankylosis of the footplate, followed by bony overgrowth anchoring it into the oval window  ° of immobilization governs severity of the hearing loss  Usually beings in the early decades of life  Most are familial inheritance following autosomal dominant transmission w/ variable penetrance  Basis for osseous overgrowth represents uncoupling of normal bone resorption and formation. Begins with bone resorption, followed by fibrosis and vascularization of the temporal bone in immediate vicinity of the oval window, in time replaced by dense new bone anchoring the footplate of the stapes.  Process is slowly progressive over the space of decades, leading to eventual marked hearing loss. Tumors:  Large variety of epithelial and mesenchymal tumors of the ear (external, middle, internal) are all rare except for basal cell or squamous cell carcinomas of the pinna (external ear):  Tend to occur in elderly men and are thought to be associated with actinic radiation  Locally invasive by rarely spread  Tumors within the canal tend to be squamous cell carcinomas which occur in middle-aged to elderly women and are not associated with sun exposure.  May invade the cranial cavity or metastasize to regional nodes accounting for a 5-year mortality rate of 50%

Neck – most are components of systemic disorder, but there are a few uncommon lesions unique to the neck Branchial Cyst (Cervical Lymphoepithelial Cyst):  Benign cyst thought to arise from remnants of 2nd branchial arch  Location – usually appear on upper lateral aspect of the neck along the sternocleidomastoid muscle.  Morphology – cysts are well circumscribed, 2-5 cm in diameter, with fibrous walls usually lined by stratified squamous or pseudostratified columnar epithelium. Cyst wall typically contains lymphoid tissue with prominent germinal centers. Cystic contents may be clear, watery to mucinous fluid or may contain desquamated, granular cellular debris.  Clinical Manifestation – commonly observed in young adults between the ages of 20-40. Cysts enlarge slowly, are rarely the site of malignant transformation and generally are readily excised. Similar lesions sometimes appear in the parotid gland or in the oral cavity beneath the tongue. Thyroglossal Duct Cyst:  Thyroid begins in the region of the foramen cecum at the base of the tongue, and descends to anterior neck as it develops.  Remnants of this developmental tract may persist, producing cysts (1-4 cm in diameter) which may be lined by stratified squamous epithelium (when located near the base of the tongue) or by pseudostratified columnar epithelium (in lower locations). Transitional patterns are encountered  Connective tissue wall of the cyst may harbor lymphoid aggregated or remnants of recognizable thyroid tissue.  Treatment – excision  Malignant transformation within the lining epithelium has been reported by is rare!

Paraganglioma (Carotid Body Tumor):  Clusters of neuroendocrine cells associated with the sympathetic and parasympathetic nervous systems which can be seen throughout various regions of the body.  Location – typically develop in two locations:  Paravertebral paraganglia (i.e. organs of Zuckerandl [chromaffin body derived from neural crest located at the bifurcation of the aorta or at the origin of the inferior mesenteric artery] and bladder (rarely)) – have sympathetic connections and are chromaffin-positive (stain that detects catecholamines)  Paraganglia related to the great vessels of the head and neck (aorticopulmonary chain) including the carotid bodies (most common), aortic bodies, jugulotympanic ganglia, ganglion nodosum of the vagus nerve, and clusters located about the oral cavity, nose, nasopharynx, larynx and orbit – these are innervated by parasympathetic nervous system and infrequently release catacholamines.  Carotid body tumors ore tumors of the carotid body receptor cells which are cells near the carotid sinus that are sensitive to pO2, pCO2, pH, and even temperature, and are called carotid body tumors, and appear as little round balls microscopically.  Gross Morphology - rarely exceeds 6 cm in diameter and arises close to or envelops the bifurcation of the common carotid artery. Tissue is red-pink to brown  Histology – chiefly composed of nests (Zellballen) of round to oval chief cells (neuroectodermal in origin) that are surrounded by delicate vascular septae.  Tumor cells contain abundant clear or granular, eosinophilic cytoplasm and uniform, round to ovoid, sometimes vesicular nuclei.  There is little cellular pleomorphism and mitoses are scant (meaning they all look the same and are not dividing)  Chief cells stain strongly for neuroendocrine markers such as chromogranin, synaptophysin, neuron-specific enolase, CD56 and CD57  Strong network of spindle-shaped stromal cells, collectively called sustentacular cells that are positive for S-100 protein  Electron microscopy often discloses well-demarcated neuroendocrine granules in paravertebral tumors, but their number can be highly variable and they tend to be scant in nonfunctioning tumors  Clinical Manifestation – rare, painless and slow growing. Usually arise in the 5th and 6th decades of life. Commonly occur single and sporadically but may be familial, with autosomal dominant transmission in the multiple endocrine neoplasia 2 syndome. Frequently recur after incomplete resection and may metastasize to regional lymph nodes and distant sites.  Mortality – 50% prove fatal (due to infiltrative growth)