Pathology of the Head and Neck

206 N. Gale · A. Cardesa · N. Zidar7in 1972 was 50% [164], and had fallen to 10% 14 yearslater [239]. Early diagnosis can influence a better outcome,and survival rate appears more favourable thanwas previously thought [364].7.3.3.5 GoutGout is a disorder of the purine metabolism typicallyidentified by hyperuricaemia. The disease is characterisedby temporary attacks of acute arthritis caused byprecipitation of monosodium urate crystals within andabout the joints. The course of the disease may eventuallylead to deposition of urates in the joints and othersoft tissues, creating tophi. The first attack of the diseaseis mainly monoarticular with a predilection to the firstmetatarsophalangeal joint. The head and neck regionis rarely involved, although the classic site is the externalear. In addition, tophi may appear in the intervertebraldiscs, oropharynx, temporomandibular joint,and tongue. There has been limited evidence of chronicgouty involvement of the larynx, with less than 20 caseshaving been reported so far [365]. Acute gouty cricoarythenoidarthritis is the most common and may giverise to pain within the larynx, dysphonia, odynophagia,dysphagia or stridor. After repeated attacks, the articularcartilage is gradually destroyed leading to ankylosisof the joint. The fixed vocal cord may mimic growth ofa malignant tumour [365]. Tophi of the laryngeal softtissue are exceedingly rare [146], the involved mucosaof the vocal cords shows a granular surface [228]. Thehistological features of tophi are conspicuous, with largeaggregates of needle-shaped urate crystals (birefringentcrystalline deposits) surrounded by macrophages, foreign-typegiant cells, lymphocytes and fibroblasts [146].In more remote differential diagnostic possibilities, otherlesions with deposition of various substances in thelaryngeal mucosa, such as amyloid or Teflon, need to beconsidered.7.3.3.6 Teflon GranulomaInjection of Teflon paste (polytetrafluoroethylene)into the lateral thyreoarytenoid muscle has been usedin patients with unilateral paralysis of the vocal cord,with the aim of augmenting and medialising the paralysedhemilarynx. The increased bulk of the vocal cordcould, therefore, contribute to a more complete glotticclosure, prevent aspiration, and improve a poor-qualityvoice caused by impaired breathing. The most commoncause of vocal cord paralysis is surgical trauma of thelaryngeal recurrent nerve and/or malignant tumours[31, 370, 385]. In general, Teflon injection has been welltolerated, and after a short-lived inflammatory reaction,it becomes stable and walled-off by surrounding fibrosis[31, 210]. Technical errors during injections, such as overinjection or misplaced injection of Teflon may, however,cause dysphonia and airway obstruction, as well as thepresence of a neck mass, resembling a neoplasm, in thecase of an escape of Teflon via the cricothyroid membrane[264, 370].Teflon granulomas (TGs) are submucosal polypoidlesions of the vocal cord. Histologically, they are composedof a foreign body giant cell reaction with extensionto the underlying muscle and cartilage. Teflon ispresent in foreign body giant cells, and also extracellularly,as glassy crystalline deposits that are characteristicallybirefringent under polarised light. A dense fibrotictissue is evident over time, while the surrounding inflammatoryinfiltrate is not present [385]. TG is treatedby conservative surgery, although the results are unpredictable[31]. There have been no reports of cancer developmentin TG [385]. With the introduction of laryngealframework surgery and medialisation laryngoplasty,fewer centres nowadays additionally advocate Tefloninjection [370].7.3.3.7 Idiopathic SubglotticLaryngeal StenosisIdiopathic subglottic stenosis (ISS) is a rare, slowlyprogressive inflammatory disease of unknown aetiologyinvolving mainly the region of cricoid cartilage andthe first tracheal ring. The pathogenesis of the diseaseremains hypothetical. ISS has recently been associatedwith various possible causes, such as gastro-oesophagealreflux, autoimmune diseases and previous infectionsof the respiratory tract [30, 174, 369]. Maronianand co-workers suggested that the term ISS shouldeven be replaced by reflux-induced subglottic stenosis,if there is no other clear cause of the disease [229]. ISShas a strong female predilection [73, 132, 369]. The ageof females when the symptoms start to appear rangesfrom 15 to 75 years (average 43.5 years) [73].The diagnosis of disease is a matter of exclusion, andall other possible causes of a subglottic stenosis mustfirst be ruled out. Aetiologically, subglottic stenoses aremost commonly linked to endolaryngeal trauma, especiallyafter prolonged intubation. Other diseases, includinginfections, laryngotracheal localisation of systemicdiseases such as Wegener’s granulomatosis andother collagen vascular diseases, amyloidosis and sarcoidosis,are rarely associated with laryngeal stenosis.Various benign and malignant tumours may also resembleISS [132, 281]. ISS usually presents as dyspnoea,a cough and dysphonia [30, 73, 369].Histological examination characteristically showsa spreading of dense fibrous tissue, extending up tothe surface of the epithelium. Fibrosis is usually poorlycellular, with prominent augmentation of thick col-