Background: In the Betaseron/Betaferon in Newly Emerging Multiple Sclerosis for Initial Treatment (BENEFIT) study, interferon beta-1b delayed conversion to multiple sclerosis in patients with a first clinical event and at least 2 clinically silent brain magnetic resonance imaging (MRI) lesions.

Two patients are described in whom syncope was the presenting clinical feature of an undiagnosed neck malignancy. Both patients also had attacks associated with paroxysms of severe neck pain. Neither patient responded to cardiac pacing. R ecurrent syncope as a complication of recurrent neck malignancy is an uncommon but well documented association. 2However, syncope as the presenting feature of previously undiagnosed neck malignancy is exceedingly rare.3-5 The exact mechanism of the syncope is uncertain; however, a suitably placed neck mass is presumed to cause irritation of afferent fibres from the carotid sinus and body, travelling first in Hering's nerve and then in the glossopharyngeal nerve. Abnormal excitation of these afferent fibres causes excessive vagal activity. Syncope occurs because of bradycardia or asystole and usually prominent vasodepressor hypotension. The mechanism of syncope is therefore similar to that of idiopathic carotid sinus hypersensitivity, which consists of both cardioinhibitory and vasodepressor components in varying proportions.We describe two patients in whom syncope was the presenting clinical feature of an undiagnosed neck malignancy. Both patients also described attacks associated with paroxysms of severe neck pain. CASE 1A 59 year old man attended his local hospital emergency department having lost consciousness for two minutes after a brief episode of sharp left sided neck pain while driving. Physical examination, chest x ray, and brain computed tomography (CT) were normal. He was discharged home.He continued to experience occasional left ear pain until two months later, when he had two further blackouts preceded by a similar pain. During the second of these, an ambulance crew reported an unrecordable blood pressure with a pulse rate of 20 beats/min which responded to intravenous atropine.On admission to hospital, he described a three month history of intermittent left sided tongue numbness, a change in voice quality, dysphagia, and 4 kg weight loss.In hospital, he suffered a further episode of sharp neck pain, beginning in the left ear spreading to the left side of the neck and throat, lasting for 30 minutes, when the patient began to feel faint. This was followed by sudden loss of consciousness and urinary incontinence with a blood pressure of 90/60 mm Hg and pulse 30 beats/min. He recovered consciousness spontaneously after 30 seconds.A temporary pacing wire was placed but he had a third episode with blood pressure falling to 77/40 despite a satisfactorily paced heart rate. He was subsequently transferred to this hospital. There was no other relevant medical history.Physical examination revealed a left posterior pharyngeal mass, a left 12th nerve palsy, and a left Horner's syndrome. A dual chamber permanent pacemaker was implanted. However, he suffered two further attacks, with no clear precipitant, during which the pulse rate was normal but blood pressure fell to systolic value of 70 mm Hg, each time with spontaneous recovery. CT revealed a large mass in the left paraphar...