Diagnostic Investigation Of Lymphadenopathy

What historical information helps to direct the diagnostic investigation of lymphadenopathy?

It is unusual for a patient older than 40 years to have nonspecific lymphadenopathy; over 70% of enlarged cervical lymph nodes in this age group are malignant. Patients younger than 40 years are more likely to have a nonspecific or infectious cause, although the mean age of Hodgkin's lymphoma diagnosis is 32 years.
The duration of adenopathy helps with the diagnosis. A newly enlarged lymph node is more suggestive of infection, although an enlarging lymph node can undergo internal hemorrhage with a rapid increase in size. Travel and occupation history, exposure to pets, geographic area of residence, and sexual history provide clues to infectious agents. A history of smoking is associated with lung, upper gastrointestinal, and head and neck malignancy.
Systemic symptoms, including fever, weight loss, night sweats, and pruritus, are present in 30% of patients with Hodgkin's and 10% of patients with non-Hodgkin's lymphoma.