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Thyroid swellings (goitre or nodules) are the commonest cause of a painless, progressive mid-line neck mass in adults, especially in middle-aged women, whereas thyroglossal cysts predominate in children and other listed structures rarely enlarge in this fashion. Clinical series note that “thyroid goitre usually presents as a mid-line lump in the neck” in adults (Lakhani, 2010, PMID 20501008) and report middle-aged women with anterior midline neck swellings ultimately diagnosed as multinodular goitre (Chaurasia, 2013, PMID 24068513).