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node can't become swollen just because of smoking
Lymph from any tissue passes through respective lymph nodes before mixing in main blood stream. These act as barriers.
Whenever there is any infection in the catchment area of lymph nodes, it becomes swollen.
Thus whenever any lymph node is swollen and tender, doctor should examine its catchment area to find out the cause to treat accordingly.
F.N.A.C. test help to identify the cause.
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