Neck masses are common in children an adults, with the most common cause being reactive cervical lymph nodes. The majority of such nodes are as a reaction to simple upper respiratory infections serious pathology is rare. Reactive nodes will frequently fluctuate in size and will often increase in size with subsequent URTIs.
In some cases where the nodes are multiple and increase in size, night sweats, fevers, weight loss or other symptoms occure, further investigation may be advised. This may include an FNAC ( fine needle aspiration cytology) , or a biopsy to exclude other underlying pathology.