Familial Nasopharyngeal Carcinoma 6

Natural History, Presenting Symptoms, and Diagnosis of Nasopharyngeal Carcinoma 43Table 4.1. Incidence of cranial nerve deficit from selectedseriesSeries Country N Percentageof patientswith cranialnerve deficitTurgut et al. (1998) Turkey 124 39Sham et al. (1991) Hong Kong 262 13Leung et al. (1990) Hong Kong 564 12Lee et al. (1992) Hong Kong 5037 18Chang et al. (2005) Taiwan 3871 10Heng et al. (1999) Singapore 677 12Sanguineti et al.(1997)Perez et al. (1992)USA(Houston,TX)USA (St.Louis, MO)378 8143 23can be involved. The reported rates of cranial nervepalsy vary among studies (Chang et al. 2005; Henget al. 1999; Lee et al. 1992; Leung et al. 1990; Perez etal. 1992; Sanguineti et al. 1997; Sham et al. 1991;Turgut et al. 1998). Cranial nerve deficits can occuras isolated or multiple cranial nerve palsies. Table 4.1summarizes the incidence of cranial nerve deficitfrom selected series.The most commonly involved cranial nerves arethe V and the VI cranial nerves (Li et al. 2006; Stanleyand Fong 1997). Impairment of the function of thesenerves will result in paresthesia or numbness of theface and diplopia, respectively. Their involvement is aresult of tumor invasion of the skull base into the cavernoussinus (the V and the VI nerves are locatedinferiorly in the cavernous sinus and are of the closestproximity to the roof of the nasopharynx). Othercranial nerves in the cavernous sinus such as the IIInerve may be involved in more advanced cases but anisolated III nerve palsy will never occur alone withoutassociated involvement of the V and the VI nerves(Leung et al. 1990).The involvement of cranial nerves IX, X, XI, andXII can occur in locally advanced disease. Horner’ssyndrome may be present in conjunction with deficitsof one or more of the last four cranial nerves, butrarely occurs alone. In rare circumstances where thesympathetic nerve fibers surrounding the internalcarotid artery inside the carotid canal are involved,an isolated Horner’s syndrome can occur.4.3.5Eye SymptomsDiplopia on lateral gaze is a manifestation of VI nervepalsy as a result of tumor infiltration of the cavernoussinus. In very rare circumstances, proptosis canoccur as a result of tumor infiltration of the orbitthrough the orbital fissures.4.3.6HeadacheHeadache can occur in patients of NPC and usuallyindicates the presence of skull base involvement. Theheadache is usually unilateral and temporoparietalin location. The headache associated with NPC isusually neuralgic in nature and is due to the irritationof the meningeal branch of the second divisionof the V nerve. The patient may experience paincaused by lifting of head as a result of posterior infiltrationof the prevertebral muscles or retropharyngeallymphadenopathy.4.3.7Paraneoplastic SyndromeIn rare circumstances, the patients with NPC maypresent with a condition called dermatomyositis asthe initial manifestation. In one of the large seriesfrom Hong Kong, 1% of the 1,154 patients with NPChad associated dermatomyositis (Teo et al. 1989).Three of the ten patients with dermatomyositis hadthe presentation of paraneoplastic syndrome priorto the clinical detection of their NPC.The skin lesions consist of distinctive hyperkeratotic,follicular, erythematous papules (Teo et al.1989). The first lesions usually appear on the face andeyelids and eventually, the neck, shoulders, and upperextremities are involved. Muscular weakness alwaysfollows the skin manifestation. Figure 4.1 shows thetypical skin rash associated with dermatomyositis.4.3.8Miscellaneous SymptomsTrismus can occur when there is involvement of thepterygoid muscles. The patient will usually be able tolocate the site of the tightness approximately 3–4 cmanterior to the temporal mandibular joint. It is very