Lymphatic malformations (LMs), primarily diagnosed in children, are uncommon in adults. Nevertheless, one should consider LM in one's differential diagnosis in cases of adult neck masses. We report the oldest known patient with an LM, a 91-year-old woman. We also provide a review of the literature encompassing all reported adult cases. Since 1828, 91 adult cases of LMs have been reported in the English-language literature. We describe the clinical findings, diagnostic methods, and therapeutic management of LMs of the head and neck. We believe that surgery remains a therapeutic option even in patients of advanced age.