Mei is a 52-year-old sales attendant who attends for review of persistent neck lymph nodes that have been present for at least two years.

She denies associated weight loss, cough, fever or sweats but does complain of chronic vague lethargy.

Her past medical history includes chronic sinusitis. An MRI of her sinuses — arranged by an ENT specialist more than a year earlier — was unremarkable.

She is otherwise very well, takes no regular medications and has no significant family history.