If a lymph
node does not reduced in size even after 2 weeks of antibiotics then definite diagnosis has to be made. Excision biopsy
is the best option in this case. At which portion of neck the lymph node was detected is an important issue, if it is more lateralised then excision biopsy will be a simple procedure and can be done under local anaesthesia. If you are worried too much then at least a FNAC can be performed but this will not be the gold standard. Please try to consult your doctor about excision biopsy as soon as possible. Otherwise valuable time will be wasted. Whatever may be the disease it is wise to pick it up quickly. Then only it will be easier to treat it otherwise unnecessary problem will be invited by you. Take care of your wife.