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What is A 45 yrs old man presents with progressive cervical lymph nodes enlargement, since 3 months; most diagnostic investigation is: and explain in detail?
In cervical lymph node enlargement, if no mucosal lesion is detected, an excision biopsy of the largest node should be performed. Ref: Harrison's Internal Medicine, 15th Edition, Page 362 and 18th Edition, Page 467.